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AIR
VOLUME V
CIRClJLAR
(AVIATION AND AEROSTATION)
BY DIRECTION OF CHIEF OF AIR SERVICE
MARCH, 1923
TECHNICAL BULLETIN
No. 33
NUMBER 426
DEVELOPMENT OF MILITARY AIRCRAFT MATERIAL FOR UNITED STATES
AIR SERVICE UNDER SUPERVISION OF ENGINEERING DIVISION.
PUBLISHED BY
ENGINEERING DIVISION, AIR SERVICE
MCCOOK FJELD, DAYTON, OHIO
1923
McCook Field-4-1 2- 23-IM
..
CONFIDENTIAL
The information contained herein is confidential and therefore
must not be republished, either in whole or in part, without
express permission of the Chief of Air Service, U. S. Army.
•
I
I
1
AIRCRAFT DEVELOPMENT
AIRPLANES
Two views of A. S. Transport T-2(Passenger) ----- ---- ----- ---- --- ---------- --------------- ------ --- ----------- 4
PW-5 Tests at Selfridge-Change1s in GA-1-New C0-1 and C0-4 models at McCook 5
Status of NBS-1 Contracts-Assembly of Barling-New TA-5 Training Arrives
Static Test of TA-6 in progress-Cox-Klemin delivers last TW-2__ ___ ___ ____ _______ ___ ____ 6
Preliminary Flight Tests of TW-3-New Ambulance Model A-L___________ ___ ___ _________________ 7
Air Service Transport T-2, structural details with modifications for Trianscontinental
Flight (illustrations) -- --- --- ------- --- -- -------------- -- ---- ----- ------------------- -- ---- --- ---- ---- ----- --------- ---- --- 7-11
New L-W-F Transport T-3-Boeing DH-4M-Thomas-Morse MB-3M Training________ 12
Propeller Developr11ent --- -- ------ -------- ----·---- --------- --------- --------- ---- --- ---- -- ------------------------ ------- ----- ---- 12
AIRSHIPS AND BALLOONS.
Design Pmgress on RS-1-U. S. M. B. Assemibled and Inflated at Wilbur Wright­Navy
Towing Airship Flown to Scott Field-Three Racing Balloons ordered­Helium
Tests at Langley FieJd,-Gas-charging Manifold-Hydrogen, Compressor
installed at Wilbur Wrigh~Non-Leak Gas Valve for Helium_________ ___________ ____ __ ___ ____ 13
Field Tests on Airship Blower-New Truck Compres.sor and Balloon Tender________________ 14
ARMAMENT.
Reworking of R-3 .Bomb Release Handles-Metal Bomb Racks-Aircraft Bomb
Truck-New Type, F-1 Gun Sight designed for Type A Mount__________ __ ___ ______________ ___ 14
ENGINES.
Dynamometer Test on Sidde ley "Jaguar''-Comparative Performance of "K"
Cyiinder with air and water cooling--Laboratory Air Conditioning Sy,stem for
carburetors-Tests on NA-U6 Car.buretor-Stromberg replaces Zenith on
Curtiss Racer ----- -- ---- -·------ ---- ----- ---- ---·-···-···------ ------·- -· -·-·---------- ---- -----·---··· --- ·- ··--------- --- ---- ---- 15
Oscilloscope for observing operation of engine ·-··--- -- -- --------······· ·-··-------·- ---··--- ----- ------------ 16
EQUIPMENT.
Underslung Fuel Tanks for Fire Prevention-Location of Landing Lights on NBS-1
-New Aeromarine Electric Starter for Libe:nty- Special T-1 Cameras for Stu-dent
Instruction ·-·-···------ ----···----·-·--- -- -·······------- -···-· ···--··-·--------- -· ·····--- ------- ---------··-··--· ···- ····- 16
New Photographic Altimeter (view)-K-1 Camera Modified for Hand-Ope:ration-
Development of Radio Equi-System for Airways ___ ----- ----- -- ---- -- ------ ---·- ------· -- -- -····----- -- 17
RESEARCH AND EXPERIMENT.
RESUME' OF ENGINEERING DIVISION SERIAL REPORTS.
Analysis of Turning--Comparfson of Air Resistance on Airship Models- Test of
Elevator Contml on Martin Bomber-Variable Speed Machine Gun Sight_____________ 18
Internally-Braced Biplane Wings-Strength of Wing Ribs-Gliders --- --- -- ·-· ---- -----·-···-- 19
Performance Test of Curtiss NBS-1 and U.S. Mail, Type W-M, Airplanes-The Use
of Water Model in Airship Design-Altitude Test of Dixie Magnetos.·- ····· ·------ ----- 20
Ball Manifold for Liberty Six Engine-Comparative Analysis of Camshaft Drive
Gear Stresses "in Liberty "12" and Packard "2025" engines- Development of
Stromberg Inverted Carburetor, Model NA-5L ····------------------ -- -------- ----- ----- -- ----- -------- 21
INVESTIGATION OF MATERIALS.
Terne Plate Fuel Tanks-Zaponite Coating for Wood Parts-Discolorations on
DH-4B Longerons-Failure of Fokker PW-5 Chas.sis in Service ······-------------··-·-·· 22
NEW BOOKS AND DOCUMENTS.
Documents Added to Engineering Division Re!ference Files ··· ···· --- --- -----······----------- -------- 23
AIR SERVICE TRANSPORT T -2 (Passenger Model)
(Description on Page 7)
)
AIRCRAFT DEVELOPMENT
ON ENGINEERING D!VISION PROGRAM
AIRPLANES
PURSUIT
Fokker PW-5 (Wright "H-2" 300-h. p. Engine)
All of the ten Model PW-5 airplanes built by Fokker on production contract have been de­livered
to Seifridge Field with the exception of one ai rplane which is undergoing calibration tests
at McCook Field.
Several minor failures due to the use of fauity material occurred during the acceptance tests
at Selfridge Field. As soon as these are overcome, the airplanes will be placed in condition and
transferred to Kelly Field, Texas, for service test.
The unsati sfactory performance of the PW-5 airplanes as reported by Selfridge Field is be­ing
investigated by the E ngineering Division.
GROUND ATTACK
Engineering Division GA-1 (Two Liberty "12'' Engines.)
The E ngineering Division has undertaken the modification of the GA-1 armored airplane to
improve its performance. The changes consist in the design and construction of a revised landing
chassis using one 44 by 10-inch wheel to replace two 36 by 8-inch wheels and the design and con­struction
of a new nacelle of welded tubing to replace the armored nacelle. The work necessi­tates
the removal of the right-hand nacelle from the airplane in storage at l\fcCook Field so that
the engine, in strument, and control installations in the new structure will be similar to those used
in the armored one.
Upon completion of the work, the tubular nacelle, drawings, and revised chassis will be for­warded
to San Antonio, T exas, for use as a model in incorporating these changes in the GA-1 air­planes
at that place.
OBSERVATION
Gallaudet C0-1 (Liberty "12" Engine)
T he fi rst production C0-1 airplane recently received from the Gallaudet Aircraft Corpora­tion
of East Greenwich, R. I., which had a contract for the construction of three airplanes on the
cost plus fixed p rofit ba'sis is being set-up at this Field for in spection and flight tests. The E n­gineering
Di,·ision has cance!led the two remaining ai rpbnes on account of the excessive cost of
the fir st article and in stituted proceedings for financial adjustment and termination of the contract.
Fokker C0-4 (Liberty "12" Engine)
T wo C0-4 airplanes have arrived at McCook F ield from Holland and are being set-up pre­paratorv
to in spection and flight test, thereby completing the first contract awarded the F okker Com­pany
for the construction of three experimental airplanes. T he new ai rplanes differ considera bly
both in appearance and construction from the fi r.st experimental model which is described and il­lustrated
in T echnical Bulletin No. 31. One airplane is fitted with a circtilar nose radiator and
the other with side radiator s.
'
6 T E C H N I C A L B U L L E T I N N o. 33
\Vork on the second contract for five production airplanes for delivery to Langley Field, Vir­ginia,
is proceeding satisfactorily. A static test model built in addition to the five airplanes on this
contract was received and tested at this Field several months ago. The production models are be­ing
constructed in accordance with this model and the changes recommended by the Division.
BOMBARDMENT
NBS-1 (Two Liberty "12"Engines)
The status on the three production contracts for eight-five NBS-1 aiq3Iane::; is practically the
same as stated in Technical Bulletin No. 32.
The Curtiss Aeroplane and Motor Corporation have completed thirty-five airplanes, including
one supercharged model which will be flown to McCook Field for test as soon as weather conditions
permit. The Engineering Division has sent a representative to the contractor's factory to inspect
the power plant in stallations previous to delivery. The contractor reports a serious hold-up in
production on this contract, due to the non-receipt of eq11ipment supplied by the Government.
This condition is clue to the railroad freight embargo which is not supposed to affect Government
shipments.
The L-\t\T-F E ngineering Company have nearly completed their contract for thirty-five
NBS-1 airplanes.
Construction of NBS-1 airplanes by the Aeromarine P lane and Motor Company under Air
Service order No. 139-22, is being delayed by the contractor's failure to make satisfactory wing at­tachment
fittings. Upon investigation of the material used in these fi ttings by the Engineering Di­vision,
it was found that the difficulty was caused by impurities in the metal. The work will pro­ceed
on the first airplane as soon as these difficulties are overcome.
NBS-1 (Six Liberty "12" Engines)
The work of assembling the Barling Bomber is proceeding at Wilbur Wright Field under
supervision of the E ngineering Division. The assembly of the fuselage, empennage, landing gear,
and the center and adjacent left-bay sections of the intermediate and lower wings has been com­pleted.
Two engines have been installed, one on the left outboard section and the other on the
right inboard section. It is expected that the work will be completed about the middle of May.
Dayton-Wright TA-5 (Lawrance "J-1" 220-h. p. Engine.)
In March, the Dayton-Wright Company of Dayton, Ohio, completed and delivered to the En­gineering
Division one training airplane, Model TA-5. which is similar in design to their side-by­side
seater, Model TA-3, but which mounts·a Lawrance "J-1" engine.
This article has been inspected and is now awaiting flight tests. Delivery was made by air, the
airplane being flow!n to McCook Field in March.
Huff-Daland 'fA-6 (Lawrance "J-1" 220-h. p. Engine).
One new TA-6 training airplane which is a redesign of the modified Huff-Daland T A-2 air­plane
employing a Lawrance engine of greater horsepower than the T.A-2 has been received and
inspected hy the Division.
Static tests on the control surfaces disclosed weaknesses in the control linkage, necessitating a
redesign and subsequent test of the walking beam and a strengthening of other vital parts.
Cox-Klemin TW-2
The last of three TW-2 training airplanes built by the Cox-Klemin Aircraft Company of Col­lege
Point, New York, has been received at McCook F ield for test. This article is fitted with a
Wright Model E engine of 180 h. p. as a result of the flight tests conducted on the second air­plane
received several months ago. T he \ i\Tright Model I engine of 150 h. p. with which this air­plane
was originally equipped did not develop suffi cient power to give a satisfactory performance.
The third article has been set-up in readiness for inspection and performance test.
•
AIRCRAFT DEVELOPMENT 7
Dayton-Wright TW-3 (Wright "I" 150-h. p. Engine.
The T\i\T-3 two-seater training airplane recently flown to McCook Field by the Dayton-Wright
Company which is manufacturing two airplanes of this model under contract awarded by Chief of
Air Service, is undergoing inspection and tests by this Division. The characteristics of this model
resemble in general construction the T A-3 side-by-side seater airplane built for the Engineering
Division by this same company.
Preparatory to flight testing, the Division found it necessary to make a number of changes, in­cluding
the in stallation of a new engine and a new radiator furni shed by the contractor. The
calibration tests have been delayed by several structural failures during preliminary flights.
MISCELLANEOUS
Ambulance Airplane, Model A-1.
The Engineering Division has just completed the mock-up for the new ambulance airplane of
biplane constructi on mounting a standard Liberty "12" engine. The design which was selected by
the Chief of Air Service from four types submitted by this Division, calls for a useful load of 720
pounds, including pilot, medical officer, and two pateints and is arranged so as to permit medical /
attention to patients during flight. The designation for this airplane will be l\'f ode! "A-1."
Air Service Transport T-2.
Early in 1922, two eight-passenger transports of Fokker F-IV design were built for the United
States Air Service by the Netherlands Aircraft Company, a Fokker firm , of Amsterdam, Holland.
and shipped to McCook Field for test. The model designation "T-2" was assigned to these air­planes
by the Air Service.
It became apparent from the results of the performance tests conducted by the Engineering
Division on one of these transports that this type of airplane was especially adapted for use on en­durance
and long di stance flights. \ i\Tith this purpose in view, the Division undertook the modifica­tions
of one transport which is described in detail in this article. Descriptions and illu strations of
both the regular model and the modified one are given for comparison.
AIR SERVICE TRANSPORT (Passenger Model).
The following description is given of the unmodified T-2 Transport with accommodations for
eight passengers. The structural features are the same for both models except as stated uncier
modifi cations of the non-stop model.
Wing.-One of the most interesting features of the con struction is the large internally-braced,
plywood wing. It is of cantilever construction of very thick section, built entirely of wood held to­gether
with glue. The structure tapers both in plan and in elevation from the fuselage to the tips
and is attached to the upper fuselage longerons as a single unit by means of onlv four hinge-bolts.
This four-bolt attachment greatly si mplifies erection and rigg;ng operations. The entire cellule
weighs 2075 pounds and has a total supporting a rea of 958 square feet.
Two continuous box spars tapering from the points of attachment at the fuselage to the tips
from the main structural members of the wing thruout its entire span. The ribs are made of Rus­sian
birch varying from 0.034 to 0.043-in. thickness with vertical stiffeners of triangular cross-sec­tion
glued to the sides of the rib web. The cap stripes are formed of 3-i -inch square pine stock
glued to the rib which in turn is attached to the spar with glued joint by pieces of wood similar to
the stiffeners.
The wing covering consists of 3-ply, rotary-cut Russian birch, 0.056-inch in thickness, which is
glued and nailed to the cap strips. The covering being very thin is stiffened by plywood _ribs and
wooden strips glued to it between the ribs.
8 T E C H N I C A L B U L L E T I N N o. 33
There is no drag-trussing in the wing structure, the covering together with the spars form­ing
a box-beam which carries the drag loads. For convenie1~ce in shipment, the rear portion of the
wing between the rear spar and the trailing edge is built-up in a separate piece in the same manner
as the rest of the wing and is fastened to the rear spar by a special slot system and brass screws
thru the covering. This portion of the wing supports the ailerons which are of the balanced type
and extend beyond the tips. Steel framework with fabric covering is used for the ai lerons.
Empemwgc.-The tail surfaces are of the balanced type and are constructed of steel tubing with
fabric covering. The stabilizer is fixed to the top of the fuselage and is supported by tubular
diagonal struts extending outward from the bottom of the fuselage. The elevators are divided
and hinged to the stabili zer. The large rudder with balanced area is attached to the vertical stern
post.
Chassis.- The chassis is built of four streamlined steel struts welded together in the shape of a
letter "'vV" as seen from the side. Round spreader tubes are welded to the pieces formed by the
two center struts with the front and rear struts at their lower extremities. Bracing is furnished
by steel strand wires crossed in the planes of opposite front and -rear struts. T he axle is continu­ous,
the shock absorber cord being wrapped around it and the lower portion of the chassis. The
chassis supports the fuselage at six points, each of which is attached to the lower fuselage longeron
by means of a pin placed perpendicular to the major axis of the cross-section of the strut.
Fuselag e.--T he fuselage is a typical Fokker structure of unusual width, built of steel tubing,
oxy-acetyline welded at the joints and braced with diagonal steel wires in each bay. The entire
structure is covered with fabric with the exception of the engine mounting where light detachable
aluminum cowling is used.
The cabin is roomy and can accommodate eight passengers and their luggage. Its location
directly below the wing affords protection to passengers in case of "nose-over" in forced landings.
Excellent view and quick egress from the cabin are afforded by means of several large windows and
two doors. The leather upholstered seats are removable to permit the carrying of freight.
T he pilot's cockpit is placed above and in front of the cabin alongside the engine which is
slightly offset to the right. This brings the propeller axis at a noticeable distance to the right of
the longitudinal axis of the airplane. A fire-proof bulkhead separates the engine from the cabin .
behind which the fuselage tapers to a vertical knife edge at the tail.
Po ..w er Plant.-The single Liberty twelve-cylinder engine of 400-h. p. is mounted in the nose
of the airplane in an offset position to the right of the longitudinal axis of the airplane. It is
equipped with a nose radiator and a two-bladed tractor propeller. The fuel tank of 130 gallons'
capacity with gravity feed is fastened on top of the fuselage longerons in such a position that it fits
into a recess in .the underside of the wing between the leading edge and the front spar, thus per­mitting
the di srnantling of the wing without disturbing the connections.
• The engine and airplane controls are within easy reach of the pilot. The exhaust gases are lead
forward and escape thru the two vertical stacks projecting above the engine cowling. The left ex­haust
pipe is encased in a larger tube to protect the pilot from the heat.
CHARACTERISTICS AND PERFORMANCE.
DIMENSIONS
Overall span .... ..... ... . . . . .... .. ...... . ........ 74' 10"
Overall length . . . . ...... ... . .... . ..... . .. ·. . . . . . . . 49' 1"
Overall height . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11' 10"
Aerofoil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Fokker
Chord of wing (tapering) .. . ......................... 14' 11" to 8' 7~"
Incidence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0° center - 2° 15' tip
AREA
Total supporting area (wing) . . . . . . . . . . . . . . . . . . . . . . . 958 sq. f t.
AIRCRAFT DEVELOPME N T
WEIGHT IN POUNDS
E mpty (including water) .. ..... . .... . . . ...... ... ...... . . ... .. . . .. .
Equiptnent ........... . .. . ............... . . ... . ....... . . ... ...... .
Crew, ( Ballast, pi lot, and parachutes) ...... . .. . ... . . ... ... . . .... . . . . .
Fuel . ...... ... . ........... . . .. ........ . . . ... . ... .......... ... .. .
Oil .. ............ ... .. . . . . . .. . ... . .. . . .... ...... ... . ........ . . . .
T otal weight .. . . .. .. .......... . ...... . .. . .. . . ... . .. . . . ..... ... ... .
\ i\T eight per square foot. ..... .. . .. . .. . ........ . ... . .... . .. . .. .. .. . . .
\Veight per horsepower . .... .. . .. .... . .... ... .... . . ........ .. . .. . . .
PERFORMANCE*
CLIMB SPEED
Standard T ime Rate Engine Level Flight E ngine
Altitude 111 mm. ft/ min. r. p. 111. m. p. h. r. p. m.
0 400 1580 ~ ~--,1-0::-0::--.c8;:----~~~1643
6,500 25 158 1530
8,050 S. C. 37.3 100 1520
10,700 A. C. 0 1500
Endurance--4 hours.
Minimum speed at sea level-68 rn.p. h.
*Preliminary report-results not conclusive.
93.8
91.5
80.1
5037
35
2113
752
56
7993
8.34
19.58
')
Altho the performance of this airplane in the National Airplane Races at Selfridge Field,
last October, was not of particular importance in comparison with the subsequent performance of
its sister ship, the T-2 " 1 on-Stop," it may be of interest to state here that this airplane won third
place, relative to speed onl y, in the Aviation Country Club of Detroit Trophy Race for light com­mercial
aircraft. T he official time for the 257.7-mi le course w,as 2 hr. , 50 rnin ., 22.55 sec., making
an average of 90.7 rn. p . h.
MODIFICATIONS OF T-2 FOR TRANSCO_.)JTINENTAL FLIGHT.
The conception of a non-stop coast -to-coast fl io-ht was fir st announced lated in 1921 by two En­gin
eering Division pi lots. At that time, however, the ir Service had no airp lane which could be
used for this purpose without considerable modifi cation and the project was held in abeyance until
the spring of 1922 when the Transport "T-2" became avai.lable.
This airplane proved to be an efficient weight carrier and possessed fl ying cha racteri stics
favorable for such a flight. As a result, a thoro investigation of its possibilities was made by the
Division which involved a great amount of engineering work in making performance calculations
with varying loads to determine the maximum load that could be carried with safet y. an analysis
of the structure and the changes necessary to be made thereto. and determination and disposition of
the larae amount of fu el required for a flight of th is magni tude.
AIR SERVICE TRANSPORT T-2 (Transcontinental)
10 T E C H N I C A L B U L L E T I N N o. 33
The performances of the airplane "'.ere predicted by making actual flight tests at various engine
speeds with load increments vary from 6,200 to 11,000 pounds and at altitudes varynig from
500 to 10,000 feet. From these calculations, it was concluded that a non-stop transcontinental
flight could he successfully accomplished with safety by carrying sufficient fuel to last approxi­mately
2,600 miles with a maximum loading not exceeding 11 ,000 pounds at the start.
The next step was to modify the T-2 transport to accommodate the large amount of fuel with­out
destroying the balance of the airplane and also provide for structural changes and other modi­fi
cations incidental to the successful accomplishment of this flight.
For this purpose, the Engineering Division selected one of the eight-passenger transports
which was modified as follows:
The modifications consi sted in the removal of the seats and other cabin equipment, the installa­tion
of two extra fuel tanks, dual controls, alterations to the pilot's cockpit, and power plant
changes together with additional bracing to the wing structure.
The fu el capacity was increased from 130 gallons, the normal capacity of regular gravity t:.nk
located in the leading edge of the wing to 725 gallons by in stalling a 410-gallon tank betwe<'n the
wing spars and a 185-gallon tank in the cabin. T he tank in the wing was supported by seven spruce
beams shaped to fit the tank and attached to the spars whereas the tank in the cabin was sup­ported
by a steel framework. The layout of fuel system is shown in the accompanying sketches.
19/K .f:i.£/lSE
J WRY COCK
/'Ulfl"
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SltVT orr C OC'K'.5
FUEL SYSTEM ON T _2
2'
The fuel system was operated by an engine­driven
bellows pnrnp fed from the fuselage tank
which was supplied by a system of lines from the
wing tanks. In case of failure of bellows pump.
the fuel could be forced into the 130-gallon tank in
the wing by mean5 of a hand-operated wobble
pump in the rear cockpit and from there fed to
the carburetors by gravity and air pressure furn­ished
by a small hand air pump in the front cock­pit.
The only changes in the oil system included
the insta llation of a 40-gallon oil tank and an oil
radiator. The cooling system, was augmented by
the addition of a reserve water tank placed in the
cabin and an auxiliary radiator equipped with
shutters which was installed below the nose of the
fuselage parallel with the large radiator.
,r..,11 The engine used for the flight was a new Lib-erty
"12" manufactured by the Ford Motor Car
Company. It was fitted with stub-tooth gear
train s, a new set of cylinders, oil-groove pistons,
and new ignition wiring. It was given the regular
overhaul and test usually accorded reconditioned
engines. A series of special fuel consumption tests were nm on the dynari1ometer to determine the
carburetor settings.
Other modifications for the comfort and convenience of the pilots consisted in the in stallation
of a dual set of controls, the extra set being placed in the fuselage to make it possible for the rear
pilot to control the airplane during the interchange of pilots. The front cockpit was provided with
a folding seat and a door in the front wall of the cabin thru which the pilot could enter it. A set
of airplane wheels and t ires, size 44"x10", was substituted for the original wheels and tires. T he
tires were of six-ply walls to reduce weight.
The records attained by the Division's two well-known pilots in the modified T-2 transport will
not be discussed 'in this article, the purpose of which is merely to cite the technical problems that
had to be solved to make these records possible.
AIRCRAFT DEVELOPMENT 11
The engineering features involved in a transcontinental flight apply with equal force to those
req uired in an endurance fli ght and any inaccuracy in the calculations are liable to result disas­trously.
Views of both transports are given in tl1is number. The records establi shed by the "Non­Stop"
model will be treated in a future article.
WEIGHT ESTIMATES FOR MODIFIED T-2.
(Pounds)
Weight empty (with water) .......... , ....................... 5047
Extra water, 10 gal................................. ................ 80
Extra gasoline tanks (165+360) .......................... 525
Extra oil tanks ... -..................................... ................ 35
2 Parachute flares .................................................... 72
2 Crew, parachutes and food ........ ... ,...................... 400
Extra bracing for gas tanks and controls............ 200
6359
Weight removed (star t er, battery, seats and
fittings) ........... - .................................................... ~
6159
Gasoline- 130+ 410+185 = 725 gal. at 6 lb.
per gallon ............ . ............................................... 4350
Oil-35 gal. at 7 lb. per gallon .................... a.. .. ..... 245
10,754
Total wing area .................. 958 sq. ft.
Liberty engine .................... 423 h. p. @ 1700 r. p. m.
Wing loading ...................... 11.5 lb /sq. ft.
Power loading ............. _ ..... 26 lb/ h. p.
MODIFICATIONS OF T-2-ARRANGEMENT OF FUEL AND OIL TANKS AND DUAL CONTROLS.
12 T E C H I C A L B U L L E T I N N o. 33
New Transport T-3.
Preparatory to awarding the contract for ten transport airplanes, to be known as Air Service
Mode! "T-3", the Engineering Division is building a wind tunnel model of the design subm'itted
by the L-vV-F Engineering Corporation, of New York, to determine the aerodynamical character­istics
and design data.
The L-W-F design provides for a biplane construction mounting one Liberty "12" engine and
accommodations for six passengers and two pilots, t he pilot's cockpit being located forward and
above the passenger cabin.
Boeing DH-4M.
In Fehruary, a contract was awarded to the Boeing Aircraft Company, Seattl e. v\Tashington,
for the redesi~n and r ebuilding of three standard American-built DH-4 airplanes into special air­planes
of the same general type to be known as "DH-41\1."
The DH-4M model is to have a steel tubular fu selage with fabric co,·ering with p rovision for
the installation of an underslung fuel tank. The regular DH-4 wfngs, tail surfaces, landing gear,
and other standard parts are to be used in the construction. One airplane will be completed only
insofar as is necessary for use in static test. The other two will be used for flight test.
Thomas-Morse MB-3M.
One of the standard production MB-3 pursuit airplanes L,uilt for the Service hy the Thomas­M
or5e Aircraft Corporation, Ithaca, N. Y ., has been remodeled by the Division into an advanced
training type, designated "MB-3M". As soon as fli ght tests are completed, this a irplane will be
shipped to San Antonio, Texas, for use as a model.
Propeller Development.
The E ngineering Division is doing considerable experimenting on new t)1)es of propellers with
two. three, and four blades constructed of various materi als such as wood, micarta, steel, and dural­mn.
111.
Destructive tests on detachable blade propellers built of a combination of 1n.icarta with wood
or with cloth indicate that the cloth-micarta combination i superior to the wood combination.
A solid steel propeller desia ned for use on a 300-h. p. \ i\T right engine failed after five minutes'
run on torque stand. This failure was caused by vibration stresses set-up by the engine at the base
of the blade. A defect in the material a lso contributed to t his failure . Several types of steel pro­pellers
are being experimented upon.
An experimental propeller was constructed for use on the new RS-1 airship. This propeller is
17,Y:; ft. in diameter and is designed to absorb 570 h. p. Due to the material and method of con­struction,
the weight approximates 100 pounds.
An interesting test was made on a propeller desig ned fo r use on a pursuit airplane to determine
the possible chances of fai lure while in flight after having been pierced bv delayed fire from aircraft
gun mounted on the airplane. Previous to the test. the p ropeller was mounted on the ai rplane on
the ground and five 50-caliher machine gun bullets fire thru each blade. The propeller fai led at
2100 r.p.m.
Several types of duralumin propellers have been designed and tested. One of these intended
for use on the Curtiss R-6 Racer withstood a whirling test of ten hours at 700 h. p. (2205 r . p. m.)
satisfactory. Further tests of the propeller moun~ed on the Curtiss D-12 engine at full throttle will
be necessary before it can be safely used on this airplane.
In this connection, special propellers designed and built by the DiYi sion we;·e used in estahli sh­ing
the One-Kilometer records (Jl l March 31.
AIRCRAFT DEVELOPMEXT
AIRSHIPS AND BALLOONS
Semi-Rigid Airship RS-1.
13
Satisfactory progress is being made on the design of the new 700,000-cubic foot semi-rigid
under construction for the Air Service by the Goodyear T ire and Rubber Company. Stress
analyses are in progress on different units of the structure and the design for the control car has
been partially approved by the E ngineering Division.
It is expected that the three power tran smissions which are being built for the RS-1 by this
same company will be ready for test in May.
U. S. M. B. Airship.
The assembly of the new Observation Airship, Model 1_ . S. M. B .. built for the A.ir Service
by the Airship l\fanufacturing Company of America has been completed at Wilbur ·wright Field
where the Airship Operating Station of the Engineering Division is located owing to the lack of
sufficient space at McCook Field for c;-1rrying on rhis wo rk.
The envelope has been inflated with hydrogen in preparation fo r the test flights to be held
shortly.
Navy Towing Airship.
The Navy Towing air ship, Air Service T ype A-5, was flown from \ ,Vilbur ·wright Field to
Scott Field, Illinois, on March 8, 1923, for continuation of service tests af ter being overhauled and
conditioned by the E ngineering Division.
The work clone by the Division included the in stallation of Lawrance L-4 engine in place of
the L-3 engine with which the ai rship was equipped. Several satisfactory flights were made and
dropping tests conducted with parachutes adapted to lighter-than-air craft.
Racing Balloons.
Purchase orders have been issued to the Aircra ft Development Corporati on of Detroit for one
80.000-cubic foot racing type spherical balloon as designed by that firm and to the Goodyear Tire
and Rubber Company for two 80,000-cubic foot racing type spherical balloons as designed by the
Engineering Divi sion. These balloons will be used in the International Ball oon Races to be held
this spring.
Helium Tests with Military Airships.
The helium tests with military airships, con:luctecl at Langley F ield under the superv1s10n of
this Di vision, were concluded on J anuary 31 , 1923. A completed report is being compi led on the data
obtained during comparative flights with an airsh"p inflated with hydrogen and with helium. From
the data so far investigated. the use of helium with r egard to low permeability and decrease of gas
purity apparently gives better results than originally antic ipated.
Portable Gas-Charging Manifold.
A gas-charging manifold of the portable type developed by the Division is undergoing pre­liminarv
tests at the plant of the Dayton Oxygen and Hydrogen Prod ucts Company with sati sfac­tory
results. Service tests in the F ield wi ll be conducted in connection with the tests on a new truck
compressor nearing completion.
Stationary Gas Compressor.
A stationary gas compressor is being in st;:ill ecl at the Airship Operating Station at \ i\Tilbur
W rig-ht Field. \ i\Tith this in stallation completed, a ll new de\·eloprnents in gas va lves and gas­charging
apparatus can be tested .
Non-Leak Gas Valve.
A new non-leak gas cylinder valve developed bv this Division for use with helium has been
under test for over three weeks and is giving sati sfactory results.
14 T E C H N I C A L B U L L E T I N N o. 33
Airship Blower.
An electrically-driven blower, designed to deliver 1800 cubic feet of air per minute against a
pressure of a one-inch water column, has been given a fi eld tests which indicates that an initial
ynltage of 14 instead of 12 volts will he necessary to obtain full performance during flight. The
blower was developed as an accessory for the U . S. M. B. airship or motori zed observation balloon.
Its purpose is to overcome gas constri ction incident .to hauling clown a 50,000-cubic foot airship
at a rate of 1000 feet per minute with the engines shut off.
The blower complete, without battery, weighs 46 pounds and requires about 34 h. p. in full
operation.
New Transportation Equipment.
Two new additions have just been made to the Division's Lighter-than-Air t ransportation
equipment consisting of one experimental light weight truck compressor and one balloon tender, the
contracts for which were placed with T he Steel Products Engineering Company of Springfield,
Ohio, last June.
Truck C 011-ipressor.-This apparatus consists of a chassis, similar in design to that of the
Highly Mobile Balloon \ i\Tinch illustrated in Technical Bulletin No. 28, mounting a high duty Ster­ling
four-cylinder motor with special type of transmission and Freeman type axles. It has a four ­wheel
drive with the usual type of universal joint eliminated. Steering is easily accomplished
even under capacity load with the same facility attained by standard rear-wheel-drive trucks.
The compressor was built by the \ ,Vorthington Pump and Machinery Company especially for
the truck. It is of the three-stage vertical type and is balanced to eliminate vibration. The ca­pacity
is 5000 cubic feet of gas per hour compressed to 2000 pounds pressure. The compressor
can be used for either hydrogen or helium.
Two radiators are employed, one for cooling the engine and the other for the comp ressor.
The whole unit is very flexible; any two wheels, diagonally opposite, may be raised a distance
of one foot without cramping the drive in any way. The truck weighs 12,600 pounds, is provided
with eight speeds forward, and is capable of attaining a speed of 35 m. p. h. on fair roads. It is
constructed to negotiate soft ground and steep inclines such as are encountered in marshy terrain.
shell holes, and gravel pits.
Balloon Tenclcr.- An experimental chassis for a balloon tender was built and delivered hy The
Steel Products Engineering Company on the same contract as the compressor uni t.
The balloon tender chassis which is now undergoing tests has the same type of axle as that
used in the T ruck Compressor Unit and the H ighly Mobile \ i\Tincl1. In all three machines. the
transmission, axles, and wheels are interchangeable. A special type of body will be built and
mounted on this chassis. The body will be equipped with auxiliary apparatus for use with balloons
such as machine gun tripods, balloon chests, and other equi pment.
ARMAMENT
Bombing Apparatus.
Type R-3.- F ifty-four out of one hundred thirty bomb release handles, Type R-3, distributed
thruout the service, have been returned to this Divi sion for reworking. v\Tork on eight of these is
being expedited for installation on airplanes being p repared for foreign shipment.
Metal Bomb Racks.-Tests on steel and duralumin beams for bomb racks indicate that altho
the duralumin beams ha\·e to be made of t hicker material , a considerable saving in weight can be
obtained.
Aircraft Bom,b Truc/i.--Recom!l1endations have been made to the Quartermaster Corps foi· the
production of one cargo truck chassis, Model TTL, to be equipped with special body and bomb­handling
equipment built according to drawings and specifications prepared by the Division. T his
,·elucle is to be constructed for the Air Seryice for use as an aircraft bomb truck.
Gun Sight Type F-1.
The Division has begun the design and construction oi a wind vane sight, T ype F -1 , which is
to be used in connection with Type "A" ring mount.
AIRCRAFT DEVELOPMENT
ENGINES
(Air-Cooled Types)
Siddeley "Jaguar".
15
A Siddeley "Jaguar" 14-cylinder air-cooled engine was acquired from the A rmstrong-Siddeley
Company, of E ngland, by the Division for experimental purposes.
This engine of Briti sh manufacture is of the radial type with its fourteen cylinders arranged
in two concentric rows of seven each. The bore and stroke are 5 and 5 Vi inches respectively giv­ing
a normal rated hor sepower of 325 h. p. at 1500 r. p. rn. This type of engine is equipped with
Zenith carburetor, magneto 'ignition, and compressed-air sta rter. It operates on a compression ratio
of 5 : 1 and mean effective pressure of 122.5 lb. per square inch.
Actual test of this engine on the dynamometer gave a normal output of 335 h. p. at 1500 r .
p. 111. with a maximum output of 341 h. p. at this speed and 366.8 h. p. at 1655 r. p. m. with full
throttle.
Engine Cylinder, Type K.
T he Division has been experimenting with an air-cooled cast iron cylinder of Type K design
to determine the comparative per formances of air-cooled and water-cooled cylinders of the same
construction. T he results showed that the cylinder fitted with water jackets gave approximately
the same power output at low speeds as the air-cooled model but, as the speed increased, the
power output of the water-cooled cylinder had a tendency to drop off.
(Water-Cooled Types)
Liberty "12" (Inverted Position)
T he calibration of a standard Liberty "12" engine adapted for operation in an inverted posi­tion
has been completed . ( View of inverted engine is shown in la.st issue.)
T he im·erted engine functioned satisfactorily, delivering 420 h. p. at 1700 r. p. m. Fuel con­sumption
averaged 0.05-lb. per h. p. hour, and the oil consumption 9 lb. per hour. Altl10 the oil
c:onsumption is lower than that predicted for operation in this position, it should be noted that
there was a temperature difference of 70° F . between the incoming and outgoing oil during the
one-hour run.
Air Conditioning System for Carburetor Test.
T he Division has completed and tested the installation of an air conditioning system for the
Dynarnometer Laboratory at McCook Field. The apparatus cools 1900 cubic feet of air per
mi nute, from 120° to 56° F., allowing a variation of only 2° F. By means of a thermostatic con­trol,
the apparatus will automatically condition air for supplying the carl1uretors of engines on
clynarnometer test.
Stromberg Carburetors.
Model NA-U6.-A Stromberg NA-U6 carburetor has been installed on a Wright H -3 engine
in an MB-3A airplane for flight test. In compari son with other carburetors, the NA-U6 gives a
better mixture control resulting in sn1oother operation and lower fuel consumption which increases
the range of action of the a irplane.
S tromberg Used Oil Curtiss R a.cer.-T he Division installed Stromberg carburetors on both of
the Curtiss R-6 racer s. This carburetor gives smoother engine operation and a: possibility of in ­creased
r. p. m. The Zenith carburetor originally used on this a irplane did not function above
2300 r. p. 111 . whereas the Stromberg will fu nction alx,ve 2500 r. p. m. The constrnction of the
Stromberg carburetor is such that it is possible to reduce fu el consumption, if necessary, to 0.5-lb.
per h. p. hour. For racing conditions, the fne! consumption amounts to 0.6-lb. per h. p. hour.
16 T E C H :N I C A L B U L L E T I N N o. 33
Oscilloscope (Elverson).
An A. J. H. Elverson Oscilloscope, made by Herbert Kennedy, has been purchased from E ng­land
thrn the Office of the Military Attache'.
This i1i-strument permits the observance of the rapidly moving parts of a mechanism in oper­ation
hy the apparent slowing clown movement of such parts as valves. valve springs, magneto con­tact
breakers, rocker arms, etc., so that these movement can be observed under actual working
condition s. The effect produced is ahout 1/ 100 of the actual working speed.
·EQUIPMENT
Underslung Fuel Tanks in Fire Prevention.
In an effort to secure a fuel tank installation on DH-4B airplanes that will prevent fires in case
of crash, the Division has installed an underslung tank of 80 gallons capacity on an airplane at this
station. The tank is covered w',ith a heavy rubber covering and is suspended entirely outside of the
fuselage . In event of a crash, it is expected that the tank will slide forward underneath the engine
instead of breaking directly against it and spilling gasoline over the hot engine which in present in­stallations
represents a potential fire hazard.
In fl yin·g airplane over speed course, it was found that its high speed was reduced about 4 miles
per hour as compared with the performance of the standard DH-4B. Development is being con­tinued
and a few underslung tanks are being made of aluminum to reclnce the weight, tr.e fir st
tank having been made of tin-plated sheet steel.
Landing Lights on NBS-1 Airplane.
E xperimental work is under way to find the most suitable pos1t10n for landing lights on
NBS-1 airplanes. Night flights have been made with lights in stalled on the wing tip s, and it was
found that the light on the left wing was useless, as the area illuminated thereby could not be seen
from the pilot's seat. Lights are now being instailed on the right wing tip and under the fu selage
forward of the landing gear. Further tests will be conducted on these lights on completion of the
in stallation.
New Electric Starter for Liberty (Aeromarine).
A new electric starter for the LiLerty "12" engine has been built and delivered by the Aero­marine
Plane & Motor Company. The Aeromarine starter combines in a single unit an electric
starter and magneto bracket for use on a Liberty engine. It is simple in construction and has some
very desirable features. The experimental model occupies slightly more space than the standard
Bijur starter but weighs nearly four pounds less. It has a decided advantage over tl1e Bijur model
in that the entire mechani sm of the Aeromarine starter can be di sassembled in about three
minutes. From. preliminary tests on the Prony brake, it appears capable of sati sfactorily carrying
the starter load required by the Liberty. The development is being continued with the probability
of purchasing a few redesigned models for experimental service test.
Tri-Lens Camera Used for Instruction.
A 'T-1 camera has been fitted with celluloid side plates and a number of small electric light
. bulbs arrangefl so as to show the internal workings of the mechanis.m to the best advantage. This
is one of the four T-1 cameras authorized to he purchased by \ ,Vashington. These cameras were
originally designed to have triplex glass fr onts but since the manufacturer of this glass could not
supply the shapes needed, ordinary plate glass fr onts were considered. However, in view of the
high cost of making glass plates and the probable replacement thru breakage, it has been decided to
use cellul oid. New celluloid plates can be substituted in case these plates deteriorate and di scolor
with age. It is expected that these devices will be very useful for in structing student officers and
men in the care and use of the T-1 camera.
A IR C R A FT DEVEL O P M E ,TT 17
Photographic Altimeter.
A new altimeter shown in the accompanying illu stration has been successfu lly developed by the
Engineering Division for use in photographic mapping: T he instrument is very sensitive and
is parti cularly adapted for use in maintaining con­stant
elevation. It has two dial s, the larger of
which is graduated in hundreds of feet with 1,000
feet corresponding to one complete revolution of
the pointer and the smaller dial in thousands of
feet, the scale being Oto 15,000 feet per revolution
of the small indicator. The large dial measures
5 ~ inches in diameter and the small one 1 y;
inches. The in strument weighs about 4J0 pounds.
This weigh will probably be reduced in the pro­duction
models.
The working model above described has a
more open scale than a similar type of instrument
being developed by the Bureau of Standards. The
E ngineering Division has placed an order with the
Julien P. F riez Company, instrument manufac­turers,
fo r two altimeters, one having a range of
0 to 20.000 feet and the other, 0 to 15,000 feet.
In addition to photographic work, this instru­ment
is valuable aid in bombing, night fl ying, and
performance testing or in any kind of work where the maintenance of constant elevation is im~
perative.
Modification of Service Camera, Model K-1.
A recent conference of Photographic Officers. meeting under orders from the Chief of Air
Service, recommended that the K -1 camera with automatic operation be abandoned and that the
K-1 cameras now in service be remodeled for full-hand operation. This action was taken in view
of the considerable success that has attended the use of the K-1 model when experimentally re­modeled
for full -hand operation. A model of th is camera was made up for use of the manufac­turer
in reworking K-1 's, and the new camera was designated "K-5." This action automatically ob­soletes
the K-1 and K-2 cameras, as the K -5 will fulfill all functions former ly performed by them.
For full automatic operation, the K-3 camera is now standard .
Radio Equi-Signal System for Airways.
The Equi-Signal Transmitting System for Direction F inding has undergone tests that have pro­duced
quite sati sfactory results. This system consists of a ground transmitting set connected to two
loop antennae which are set with their planes perpendicul ar to the earth , but making an angle with
each other. The imaginary line bi secting the angle between the two loops is the location of points
where the signal from each loop will be heard with equal intensity.
In the recent test, distin ctive signals were sent out over each loop. using a power input of 1 y;
kw. T hese signals were plainly he;i rd bv an airplane 200 miles away. The zone of equal signals at
this distance was only 7 miles wide at the maximum. The possibilities of this system as applied
to Airways are quite apparent. particularly when it is noted that a good receiving set is the only
equipment that must be carried in the airplane itself . F urther tests of this system will be neces­sary
to determine its reliability under all conditions of weather and servi ce.
RESEARCH AND EXPERIMENT
Analysis of Turning.
I
RESUME OF ENGINEERING DIVISION
SERIAL REPORTS.
Serial Reports mar!?ed with an asterisk ( *) will
be issued by the Chief of Air S ervice as "Air
S qrz1ice Iuf ormati()n Circulars."
AIRPLANE SECTION.
Serial No. 2071
The report gives an analysis of turning for two cases of airplane maneuvering, namely,­Steady
Motion and De-celerated l\fotion. In turning with the airplane in steady motion, the lift
is in access of the total weight or, in other words, the excess power is absorbed in producing an added
lift on the wings. From the computations, it is apparent that the limiting load determines the angle
of bank and that the radius of turning depends only on the speed which corresponds to t he limiting
load. In the case of de-celerated motion, where the motion is maintained by a constant altitude for
some length of time, the speed will drop and the radius of turn increase to steady motion values or
the airplane will lose altitude.
In general conclusion, it may be said that a pilot in an ordinary present-clay airplane may as­sume
any angle of bank from 0° to 60° in steady motion and any angle of bank from 0° to 90° in
de-celeratecl motion.
Comparison of Air Resistance on Airship Models. *Serial No. 2086
F ive airships- Models C-1, C-2, RO, SR-1 and UB-2A, representing respectively three Navy
Class "C" shapes with aspect ratios of 4.60, 4 , and 3.9 and two contour E llipsoid-Paraboloid
shapes with aspect ratios of 4.01 , were tested in the E ngineering Division five-foot wind tunnel to
determine their comparative -resistances.
T he relative resistance of the five models in the order of magnitude was found to he as fol­lows
: RO greatest, C-2, C-1, SR-1, and UB-2A least; indicating the superiority of the E llipsoid­Paraboloid
shapes over the Navy Class "C" shapes.
Test of ·Elevator Control on Martin Bomber. *Serial No. 2087
A static test was made on the elevator control system of the Martin Bomber airplane in order
to determine the force required on the control stick to actuate the elevator. T he loads imposed on
the control surfaces varied from O to 20 pounds per square inch and the re ultant pulls on the stick
are tabulated.
Variable Speed Machine Gun Foresight.
( Preliminary Design)
Serial No. 2088
T he preliminary design calculations for a variable speed machine gun foresight for use in con­nection
with the "Norm,al Wind Vane Foresight" is given in t he report. T he new sighting device
compensates for various speeds of the airplane and is not limited to a small variation of speed or
speed range like the Norman sight which operates satisfactorily at only the mean speed within this
small range.
RESEARCH AND EXPERIMENT 19
The design is discussed in detail with views of the bead arm, the compensator, and the general
assembly and in stallation.
Internally-Braced Biplane Wings. *Serial No. 2090
This report describes the properties of internally-braced biplanes which are of interest to the
structural designer and, by numerical example, indicate the proper method of design.
The subject is treated under the following divisions:
PART I-General Description of the Method of Design without numerical examples.
PART II-Numerical Example giving computations for design of Engineering Di­vision
PW-IA airplane.
PART m -Study of Static Test Results obtained on Air Service Models, PvV-lA and
TW-2, with reference to the effectiveness of the "N" strut in equalizing
deflections and distributing stresses.
APPE DIX I-Describes and illustrates the new and approved method evolved by the U.
S. Forest Products Laboratory ior determining the modulus of rupture of
"box" and "I" sections of wood.
APPENDIX II- Study of an "I" strut to replace the "N" strut used on PvV-lA airplane.
It is not generally known to designers that, in internally-braced biplane construction, the in­fluence
of stagger or incidence bracing can be very closely computed and utilized to effect a great
saving in the weight of wing spars. The principal effects of the incidence bracing are to decrease
the stresses in the lift trusses and increase the stresses in the drag trusess. Up to the present time,
the American practice has been to neglect the effect of incidence bracing on the drag trusses. This
practice is on the safe side in sofar as the lift trusses are concerned but on the unsafe side in re­gard
to the web members in the drag trusses which, fortunately, have been made oversize. It is
the purpose of this report 'to describe a method of computing this effect of incidence bracing and
to effect a resultant saving in structural weight. Several methods are recommended for use in de­sign.
Strength of Wing Ribs. *Serial No. 2093
This report sumari zes the results of a study of aJI available American data on the strength
of wing ribs in order to evolve a standard for comparison of new designs. Curves based on
strength-weight ratio have been developed for this purpose.
Practically all of the American data has been obtained from the results of tests by the Forest
Products Laboratory and· the E ngineering Division. Owing to a more extensive procedure which
is not possible to carry out at McCook Field, the data obtained on ri bs submitted to the Forest
Products Laboratory is more complete in determining the best rib for the conditions required.
T he main points of the report a re taken up under a discussion of the variables affecting
strength. the development of standard strength-weight ratio curves, the tabulation of test results, a
discussion of individual tests. and the standard strength-weight curves for low, medium, and high
incidence conditi ons. The report is illu strated with photographs of different types of wing ribs.
Gliders. *Serial No. 2094
This report is a theoretical stndy on gliders, the main purpose of which is to set forth some
clear and simple methods for an analysis of glider performance with different kinds of winds. The
military and technical value of gliders a side from purely sporting purposes, the records of foreign
glider s, and typical glider designs are di scused.
ln the conclusion, the requi sites for efficient glider design, the effects of air current and topo­graphy
on gliding, the various types of gliders, and the topographical requirements for a declivity
wind suitable for soaring are given. It is conceded that the value of gliders in training pilots, as
obsen-ation posts and targets, as well as their use in sport will yield a better knowledge of meteor­ology
to the advantage of aerial navigation by heavier-than-air machines.
20 TE CH N I CA L B UL LET I N No. 33
FLYING SECTION.
Performance Test of NBS-1 (Curtiss) Airplane. *Serial No. 2046
This report covers the performance test results of the Curtiss NBS-1 airplane equipped with
two Liberty "12" engines.
This airplane is a production model built by the Curtiss Aeroplane and Motor Corporation,
of New York; views, description, and performances of which were published in Technical Bulletin
No. 32.
Performance Test of U.S. Mail Airplane, Type W-M. *Serial No. 2097
The U. S. Mail airplane, type W-M, is a modified DH-4 type using an Aeromarine No. 2
wing section and a regular ,DH-4 mail type fuselage of greater depth. The additional mail com­partment
containing 30 cubic feet of cargo space was attained by adding a superstructure to the
bottom of the fuselage. This compartment was then faired off by a specially-designed lower en­gine
cowling and by the use of a piywoocl construction similar to turtle back used on top of the
fuselage.
The Mail plane is very similar to a regular DH-4B in all respects except the load, the maxi­mum
carrying capacity being 800 pounds. It is easy and comfortable to fly and has a good cruis­ing
speed. A complete account of the test and photographs of the airplane are. given in the report.
LIGHTER-THAN-AIR SECTION
The Use of Water Model in Airship Design. Serial No. 2067
This paper on the use of a water model in the design of airships was presented before The Air­ship
Engineering Society of Dayton, Ohio, in 1922. It treats on the use of a water model test in
determining in advance the static excellency and other design characteristics of the proposed air­ship,
thereby reducing the great expense incurred in the building of large or new types of lighter­than-
air craft.
The test consists in suspending a small model of the proposed design in an inverted position with
the car or cars uppermost. The model is then filled with water and counterweighed ; the weight of
the water acting downward represents the lift of the gas in the large airship. Whereas this force
acts in the opposite direction in the model to that of the gas in the airship, its direction relative to
the forces representing the weights of the cars, fuel, and other loads is the same so that distor­tions
in the airship may be considered as reversed from what actually occur in the model.
The water model test can be applied with better results to the non-rigid and semi-rigid types.
In the rigid types, the structural framework carries the stresses and the envelope is not subject to
much deformation. The water model obviously cannot be subjected to actual aerodynamic tests and
is of little nse until a preliminary design of the proposed airship has been made.
POWER PLANT SECTION.
Altitude Test of Dixie Magnetos. · Serial No. 2075
Due to ignition trouble on supercharged engines during actual high altitude flying above 20,000
feet, altitude chamber tests were conducted on Dixie magnetos used in these flights to determine
the cause of missing.
It was found from the tests that the ordinary aviation magneto is not suitable for use on
supercharged engines at high altitudes clue to the fact that the resistance of the spark-gap is prac­tically
constant whereas the resistance of the various air-gap insulations thruout the magneto con­struction
decreases with altitude until a point is reached at which arcing occurs. This fault ap­plies
to a battery system also, such as the Delco system, which has been used successfully for three
years on supercharged engines. However, in this system, there is only one air-gap where this arc­ing
could occur but this gap is wide enough to prevent sparking at any altitude at which airplanes
RESEARCH AND EXPERIMENT
are ordinarily flown. This is illustrated in Lieutenant Macready's record altitude flight to 40,800
feet (indicated) in which he was able to supercharge to sea level density up to apprnximately
40,000 feet, above which his "engine altitude" rose rapidly rendering further climbing impossible.
It .is probable that at this height intermittent arcing occurred across the above-mentioned air-gap
resulting in loss of power.
As a result of the tests, it is recommended that bakelite or some other material whose dialectric
strength is independent of atmospheric pressure be substituted for the air-gaps for insulation in
magneto systems and furthermore that the gap have a variable adjustment.
Ball Manifold on Liberty Six-Cylinder Engine. Serial No. 2082
The Ball intake manifold is designed for a Liberty six-cylinder engine to give a constant flow
of gases in one direction. It consists of a circular manifold with its encl curved back thru a water
jacket into the main body of the manifold at a point about six inches from the carburetor flange.
The projection of the encl of the manifold back into the main body is curved in the direction of the
flow of gas at this point.
The object of the test was to compare the performance of the Ball manifold with that of the
Mercedes type used on the Liberty Six engine with regard to power, acceleration, fuel consump­tion,
mixture distribution, and manifold depression. and also to determine if there is any rotary
motion of the gases in the Ball manifold.
The performance of the engine with Ball manifold and Zenith US-52 duplex carburetor proved
to be inferior in many respects except for acceleration and distribution, to that of the Mercedes
manifolds with Stromberg NA-SS carburetors. (The Mercedes type uses separate manifold and
carburetor for each three cylinders). It was also found that there was a rotary motion of gases
in the Ball manifold which reverses direction under certain conditions. Views of both types of
manifolds are appended.
Comparative Analysis of Camshaft Drive Gear Stresses in Liberty "12"
and Packard "2025" Engines. *Serial No. 2083
On account of the excessive wear and breakage in the teeth of camshaft drive gears on the
Packard Model 2025 engine during endurance tests, the Division decided to investigate the stresses
existing in these gears mathematically and to compare these with the stresses existing in camshaft
drive gears of the Liberty " 12" engine.
The results obtained by different methods showed that the Packard gears, as originally de­signed,
were stressed more highly than the Liberty gears and the principal cause for the fai lure of
the Packard gears was ascribed to fanlty design and weakness of structure. Another reason for
failure of these gears in the engine tested by the Division ,vas due to the fact that they had been
manufactured of poor material as was evident from the material investigation conducted apart
from this report.
Development of Stromberg Inverted Carburetor, Model NA-5L. *Serial No. 2092
The object of this investigation which extended over a period of 18 months was to improve the
accelerating and fuel consumption qualities of Stromli>erg NA-SL inverted carburetors for use on
Liberty "12" engine and also to overcome certajn defects which occurred in Service. For sake of
clearness, the report is divided into three general phases as follow$:
First Phase-Acceleration.
Second Phase-Load Compensation.
Third Phase-Low Speed Operation.
In addition, a complete study of the carburetor was carried on continuously during the period of
investigation and several improvements were made as a result of the tests.
The carburetor is manufactured by the Stromberg Motor Devices Company, of Chicago, and
operates on the same principle as all Stromberg carburetors, that is, an air-bleed main well for
acceleration and load compensation and a separate idling system for low sp~ecl operation.
The principal changes which have been incorporated in the redesigned carburetor known as
Model N A-SLA include the installation of a ne,v accelerating well and a single Venturi to replace
· the double Venturi formerly used.
22 T E C H N I C A L B U L L E T I N N o. 33
The performance of the Stromberg Model NA-SL carburetor in which the improvements
were installed and tested was improved both in engine operation and in fuel consumption but even
with these changes, this carburetor is not as satisfactory as the Zenith U S-S2 and is not recom­mended
for general use except on supercharged engines.
The Stromberg NA-SL-A model which is a redesign of the N A-SL model is more sati sfactory
for installation and maintenance. Its performance which is belieYed to be superior remains to be
confirmed hy laboratory and flight t ests. Either carburetor will be satisfactory for use with super­chargers.
INVESTIGATION OF MATERIALS
Terne Plate Fuel Tanks.
Terne plate, taken from an l\1B-3A airplane gasoline tank which had fa iled in service, did not
conform to A. S. Specification 10,209-A in regard to composition of coating. the tin content being S
per cent lower than the minimum required. Metallographic examination indicated that dirty steel
had been used for the base plate, altho sample passed the bend test requirement of the specification.
The cracking occurred where streaks of impurities. which originated in the ingot had been rolled
down to the thin sheet to form bands of weakness.
Zaponite Coating for Wood Parts.
The investigation on the use of dope, lacquer and spar varni sh as a combination coating for
wood parts was completed. A technical report forwarded thru the Military Attache' in France in­dicated
that the French Air Service was experimenting with this type of coating. Coatings were
tested, primarily as moisture-retardant coatings, and it ,vas found that thev were not as sati sfac­tory
as our present standard coating, namely. two coats of spar varni sh. T he mate1·ial tested was
Zaponite and Zaponite sealer from the Celluloid-Zapon Company.
Discoloration on DH-4B Longerons.
An investig-ation was made of sections of longerons removed from a DH-4B airplane and for­warded
by the Commanding Officer. San Antonio .A.ir Intermedi ate Depot. In formation was r e­ouested
as to whether or not di scolorations indicate fungus growth or dry rot. T he general con­clusions
are that discolorations do not as a rule indicate decay. dry rot, or fungus growth. There
was no deterioration of glue except where moisture had free access. Spruce will not deteriorate
under ordinary service conditions.
Failure of Fokker PW-5 Chassis in Service.
An investigation was made of a shock absorber cord spool, from the Fokker P vV-5, which
failed in service. The material was found to be a ( 0.30) carbon steel of inferior manufacture. The
welding was poor and the failure had occurred in the tubing, which showed a very coarse grain due
to the welding operation. T he failure wa~ judged to be a case of overstressing material which had
been weakened by fabrication. A heavier gage tubing or a telescoping tube in the p resent structure
is recommended.
Foreign.
NEW BOOKS AND DOCUMENTS
REFERENCE DATA ON AERONAUTICAL DEVELOPMENT
AND ENGINEERING IN THE L'NITED STATES AND
OTHER COUNTRIES ADDED TO THE TECHNICAL FILES
OF THE ENGINEERING DIVISION, AIR SERVICE.
AVIATION AND AEROSTATION.
Questions proposed for discussion by the permanent comrnittee at the
annual conference of the Federation Aeronautique Internationale in Rome,
Oct. 8-16, 1922. 14 p.
Syllabus for the training of naval aviation pi lots. Airplane 1922. 39 p.
Commercial aviation in France during the years 1919, 1920, and 1921.
Tr. from Le Temps, Mar. 7, 1922. 1 p.
Service report of military ai rcraft being manufactured for the French
Government. M. I. D. 2081-446. France 6756-20. Feb. 9, 1923. 1 p.
Service report on naval aviation during the second half of 1922 M. I. D.
2081-448. France 6760-\V. Feb. 9, 1923. 1 p.
French pol icy reference rigid dirigibles. Tr. from L'Auto. Nov. 22,
1921. 3 p.
Instructions covering the issue and renewal of brevets for aerial navi­gators
( Tn compliance with the Decree of Sept. 18, 1920). M. I. D. 2US1-421.
France 6596-W. January 12, 1923. 7 p .
Report of inspection trip to France, Italy, Germany, Holland and Eng­land.
i,1ade clnring the winter of 1921- 1922; by Brig. Gen. Mitchell. Lt. Clay­ton
Bissell and Alfred Vervi lle. Air Service Information Circ11lar Vol. 4-
I o. 391. ~ov. 1, 1922--206 p.
Technical Section of Aeronautics; by Andre Lesage. From Le Genie
Civil. National Advisory Committee for Aeronautics. Feb., 1923. 19 p.
Charts, diags.
List of publications of the Federation Aeronautique Internationale. Is­sues
for the months of April, 192 1, July, 192 1, December, 1921, and l\1arch,
1922, Jm1e, 1922, Sept., 1922, and Dec ... 1922.
Service report on aircraft manufactured for Spain. M. I. D. L093-72/3.
France 755-W. Feb. 9, 1923. 1 p.
Domestic.
Annual report of the Chief of Air Service for the fi scal year ending
June 30, 1922. 46 p.
D61.l / 4
C53.2/ 7
A.10.01/4
France
Al0/7
France
J-\10/8
France
D52.7 /6
Misc. French
B70.9/ 2
Al0/83
Vol. 4--No. 391
D00.12/177
D00.12/ 178
A l0/9
France
C21/18
1922-June 30
24 T E C H N I C A L B U L L E T I N N o. 33
Nomenclature for aeronautics. National Advisory Committee for Aero­nautics.
Report No. 157. 1923. 59 p. ill us. , diags. -
Awards of medals of honor. distinguished-service cross, di stingu;shecl
service medal, citations 'for gallantry in action, and awards of life saving
medal. War Dept. General orders No. 49. Nov. 25, 1922. 31 p.
Apportionment of the annual appropriation "Mileage to officers and con­tract
surgeons." Aeronautical ratings. Battles and carnp:1igns of the United
States. War Dept. General orders No. 55. Dec. 27, 1922. 5 p .
Information concerning changing "Letters of Instruction" to "Technical
Orders." Vvar Dept. Technical Order· 00-5-1. Jan. 30, 1923. 3 p.
International metric system of weights and measures. Bureau of Stan­dards.
Miscellaneous publications No. 2. Eel. 2. Sept. 21, 1922.
Air "aces" fight in war to help farmers; campaign in five states scoring
victories against ruinous parasites, using bug traps for ordnance. n. cl . . 3 p.
Army mental tests; methods, typical results and practical applications.
Nov. 22, 1918. 23 p.
National safety code for the protection of the heads and eyes of industrial
workers. Bureau of Standards. Handbook series No. 2. Eel. 2. Dec. 29,
1922.
Better tools for our scientists, engines and industrial technical men. Na­ti
c,nal Research Council. n. cl. 1 i p.
Report of work being done at Bureau of Standards on Cheaper and
better houses, work of the National Screw Thread Commission, St,mJarcl
thickness of sheet metal, etc. Feb. 6, 1923. 12 p.
Forest Products Laboratory, Technical Nots 181-189. January 15, 1923.
21 p. Diags., chart.
Monthlv list of publications issued by the Department of Commerce.
Dec. 30, 1922.
Publications of the United States Geological Survey. Dept. of the In­terior.
Dec. 1, 1922. List No. 177.
Records.
Offi cial world's records for the year 1922. National Aeronautic As­sociation,
U. S. A. n. cl. 2 p.
Service report on prizes and competitions. M. I. D. 2081-440/ 2. France
6731-W. Feb. 6, 1923. 3 p.
New speed record for seaplanes established by the Savoia 51. M. 1. D.
Italy. J an. 8, 1923. 1 p.
Speed record of the Italian flying boat Savoia S 51. n. cl. 1 p.
Report of the Grand Prix de Paris of the Aero-Club of France. Nov.
17, 1922. 2 p.
Service report on the Gordon Bennett balloon race, and the coupe Jacques
· Schneider. M. I. D. 183-75. France 6732-W. Feb. 6, 1923. 1 p.
Rules and regulations of the 1922 Rhon soaring flight contest. From
Wisenschaftliche Gesellschaft fur Luftfahrt. National Advisory Committee
for Aeronuatics. Feb., 1923. 22 p.
D61.2/37
D00.12/ 32
1922-No. 49
D00.12/ 32
1922--No. 59
D00.12/ 76
00-5-1
C54/7
D52.2/ 7
B60/ 6
Cll.2/ 17
D00.12/176
D00.12/ 70
T. N. B.
D00.12/ 97
1923
Jan. 15
C13/6
1922-Dec.
A46.2/ 8
1922-Dec.
D71.61/ 22
D52.03/ 58
D52.6/ 5
Savoia
D52.6/ 4
Savoia
D52.03/ 57
D52.03/56
D52.15/26
NEW BOOKS AND DOCUMENTS
Lessons of the 1922 Rhon soaring flights; by L. Praudtl. From Zeit­sch1
ift fur Flungtechnik und Motorluftschiffahrt. National_ Advisory Com­mittee
for Aeronautics. Feb., 1923. 6 p.
Soaring flight and the Rhone contests; by Wilhelm Hoff. Tr. from
Zeitschrift des Vereines deutscher Ingenieure, Nov. 11, 1922. National Ad­visory
Committee for Aeronantics. J uri.e, 1923. 12 p.
INSTRUCTION.
Air Service Engineering School.
Course in Airplane Instruments; by A. F. H egenberger. Air Service
Engineering School. McCook Field. 1921-22. Large document. v. p.
Drawings.
Problems in Calculus. Maintenance engineering. Course II. Air
Service Engineering School. McCook Field. n. d. 13 p.
Mainten:rnce engineering. Course II. Physical testing. 1\.ir Sen-ice
Engineering School McCook Field. Jan., 1923. Large document.
Thermodynamics. Course I. Air Service Engineering School. Mc­Cook
Field. 1farcl1, 1923. 5 p.
Course in Aerial Photography; notes by S. M. Burka, Air Service, En­gineering
School. McCook Fiekl, 1923. 22 p.
RESEARCH.
Research in American after the war; by R. A. Millikan. Dec. 11, 1913.
12 p.
Tropical discussion on cooperation in industrial research; by Edga:- Mar­hurg.
From Proceedings of the Ameri can Society for Testing Materials. Vol.
18. Pt. 2, 191S. 61 p. .
Organization of research; by J. R. Angell. From the J onrnal of pro­ceedinl!
s and addresses of the Association of American universities. Nov.
7-8 .. 1919.
Origin , foundation and scope of the National Research council; a report
made to the Engineering Foundation. Feb. 27, 1917. 8 p.
Organization and members of the National Resea.rch Council, 1920-1921.
45 p.
Division of Engineering of the National Research Council in cooperation
with E ngineering F oundation. Jan., 1921. 16 p.
Research Committees in educational research; by G. E. Hale. National
Research Council. From Proceedings of the National Academy of sciences.
Vol. .3, Mar., 1917. p.
Progressive production; by Capt. G. J. Ecling. Procurement Division.
Air Service. n. d. 33 p. Drawings.
Airplane design graphs for performance and maneuverability; by \V. ·F.
Gerhardt and F. \ V. Herman. n. cl. 19 p. Charts.
New methods of plotting the performance of an airplane from the polars
direct; tr. from Technique Aeronautique, Dec. 15, 1922. 8 p.
Simplified performance computation; hy Maj . Leslie MacDill. Airplane
Section. McCook Field. Jan. 29, 1923. 40 p. Charts.
C71.6/59
C71.6/ 53
D13.3/ 10
q0.09/ 3
D00.11 / 122
D52.4/ 1
A30.2/ 33
D00.12/ 169
D00.12/ 170
D00.12/ 165
D00.12/ 172
D00.12/ 173
D00.12/ 171
D00.12/ 162
D00.17/ 10
D00.11 / 125
D00.11/ 123
D00.11 / 124
25
26 T E C H N I C A L B U L L E T I N N o. 33
Tests on an airplane model, A. E. G. · Dl of the Allgemeine Elektricitats
Gesellschaft, A.-G.; airplane construction section conducted at the Gottingen
model testing laboratory for aerodynamics; by Max Munk and Wilhelm Molt­han.
From Technische Berichte, Vol. III, Part 2. National Advisory Com­mittee
for Aeronautics. Technical Notes No. 12S. Feb., 1923. 26 p. Charts,
cliags.
Tandem aerofoils; by J. L. Nayler and vV. L. LePage. Aeronautical Re­search
Committee. Reports and Memoranda No. 804. Ae. 57) T. 1634.
1922. 12 p., charts.
Air force and moment for Gottingen No. 256 aerofoil. Navy Yard.
Construction Dept. Report No. 210. Dec. 23, 1922. 6 p. Charts.
Air force and moments for Loening M-80 airplane. Navy Yard Con­struction
Dept. Report No. 211. January 11, 1923. 6 p. Tables, drawings,
photograph, charts.
Air forces and moment for NW airplane. Navy Yard. Construction
Dept. Report Nio. 208. Dec. 12, 1922. 14 p. Photograph, charts, drawings.
Aerodynamic loading of airships; by L. Bairstow. Aeronautical Re­search
Committee. Reports and Memoranda No. 794. (Ae. 51) T. 1670.
Sept., 192L 8 p. Diags.
Spherical aberration of thin lenses; by T. T. Smith. Bureau of Stan­dards.
Scientific papers No. 461. Dec. 19, 1922. 26 p. Charts.
Rate of exhaustion of a closed tank by a reciprocating air pump; by
Edgar Buchingham. Bureau of Standards. Techology papers No. 224. Jan.
1, 1923. 8 p.
Carbon formation as influenced by the temperature of the substance upon
which the formation takes place. n. cl. 3 p. Photograph.
Technical Notes No. 18 1-No. 189. Jan. 15, 1923. 22 p. Diags.
Reduction of the effective value of Young's modulus in flexible com­pression
members; by A. J. S. Pippard. Aeronautical Research Committee.
Reports and Memoranda No. 792. (Ae. 49). T. 1704. Apr., 1923. 8 p.
Chart.
Report of work being clone at the Experimental Institute of Aeronautics.
In Italian. M. I. D. 2086-223/ 7. Italy 6907 G-2. Dec. 15, 1922. 53 p.
Drawings, charts.
Contents:
1. Interpretation of hydro-dynamic experiments for the determ'ination
of the characteristics of the "take-off" of seaplanes.
2. Calculations on equilibrium stability.
3. Notes on the best position for variable loads from the point of
view of equilibrium and longitudinal stability.
4. Reaction of dimethyl-glyoxim on ferric and ferrous salts.
5. Appendix containing; notes on various recent publications on
eronautical subjects.
Model supports and their effect on the results of wind tunnel tests ; by
D. L. Bacon. National Advisory Committee for Aeronautics. Technical
notes No. 130. Feb., 1923. 8 p. Charts, cliags.
D52.l/ 8
A. E.G.
D00.12/804
R. &M.
D52.338/ 156
D52.l/ll
Loening
D52.1/ 1
N.W.
D00.12/ 794
R.&M.
A48.2/91
D52.46/ 45
Dll.33/ 11
D00.12/ 97
1923
Jan.
D00.12/ 792
R.&M.
D00.12/ 117
1922
2a-No. 4
F78/ 63
General.
NEW BOOKS AND DOCUMENTS
AIRCRAFT
(Heavier-than-air)
Type, class and model designation of airplanes. Navy Dept. Bureau of
Aeronautics. Technical Note No. 235. (Supersedes Technical Note No.
213.) March 10, 1923. 2 p.
Average duration of life of different types of airplanes, excluding actual
war risks but including training risks; by Statistical Division, Air Industry.
Mar. 17, 1919. 7 p.
French service aircraft as of 192]. 2 p.
Present status of ,airplanes in use in the Royal Air Force. England 13.
R - 14132. July 5, 1922. 3 p. .
Information on foreign airplanes now being called by Japanese names.
1921. 1 p.
Characteristics of airplanes and seaplanes exhibited at Paris aeronautical
salon, Dec. 15, 1922- Jan.2, 1923; prepared by technical assistant in Europe
of the National Advisory Committee for Aeronautics. 1 p.
Metal airplane construction; by Hugo Junkers. Royal Aeronautical So­ciety.
Jan. 4, 1923. 6 p.
Construction of the Antoni wing. Apr. 18, 1922. 2 p. photographs.
Some notes on the design, construction and operation of flying boats;
by Maj. J. D. Rennie. Royal Aeronautical Society. Jan. 18, 1923. 14 p.
A vro-Aldershot.
Summary of trials of theAvro Aldershot, Handley-Page Handley, per­formance
test of the Arn1strong Sidcleley "Jaguar" engine and data on the
Napier "Cub" engine. M. I. D. 2083-570/ 3. England 14907. Jan. 30, 1922.
7 p. Photostatecl photographs.
Bleriot-Spad.
Service report giving characteristics of th Bleriot-Spacl, type 56. M. I.
D. 2081-346/ . France 6707-W. Jan. 31 .. 1923. 2 p. Blueprinted drawings.
Service report on Bleriot-Spacl monopiane pursuit type 61 airplane. M.
I. D. 6081-346/ 7. France 6700-W. Jan: 30, 1923. 1 p. Blueprint.
Borel.
Characteristics of the Borel CAP2 metal airplane, equipped with 300 H.
P. Hispano-Suizc1 engine. n. cl. 2 p.
Service report on the characteristics of the Borel transport, tri-motored
monoplane. M. I. D. 2081-443. France 738-W. Feb. 6, 1923. 3 p.
Drawings.
Curtiss.
Catalogue of Curtiss JN4H and 6H airplanes; compiled by Property
Maintenance and Cost Compilation Dept., Fairfield Air Intermediate Depot.
Oct., 1921. 8 p.
D52.l/120
D52.l/118
D52.l/27
Misc. French
D52 .. l/28
Misc.
British ,
D52.l/5
Misc.
Japanese
D52.15/ 17
D52.16/9
D52.33/ 119
D.52.16/12
Al0/14
Great
Britain
D52.l/42
Spad
D52.l/ 40
Spacl
D52.l/ 6
Borel
D52.l/ 10
Borel
D52.l/74
Curtiss
27
28 T E C H N I C A L B U L L E T I N N o. 33
Catalogue of Curtiss _TN4D airplanes; compiled by Property Mainten ­ance
:rnd Cost Compilation Dept. Fairfiiekl Air Ir.termediate Depot. Dec.,
1921. 55 p.
De Haviland.
Catalogue of DeHaviland 4B airplane; compiled by Property Mainten­ance
and Cost Compilation Dept. Fairfield Air Intermediate Depot. Oct.,
1921. 121 p ..
Eng. Div. GA-1.
Catalogue of G. A.-1 airplane; compiled by Property Maintenance and
Cost Compilation Dept. Fairfield Air Intermediate Depot. Dec., 1921. 91 p.
Hanriot.
Service report of the Hanriot HD 14 ( 1923) sometimes called the HD28
biplace training plane. M. I. D. 2081-425/2. France 6662-W. Jan. 26,
1923. 2 p. Photographs.
Service report on the characteri stics of the Hanriot HD14 bi-place train­ing
type. M. I. D. 2081-425. France 6661-W. Jan. 26, 1923. 2 p. Photo­graph.
S11pplementary report on Hanriot CAP 2 HD 15 airplane. M. 1. D.
2081-430. France 6652-W. January 24, 1923. 2 p. Photographs.
Service report on Hanriot HD19 advance training type airplane. M. I.
D. 2081-427. France 6668-W. Jan. 26, 1923. 2 p. photographs.
Service report on the Hanriot HD24 expeditionary type ( T. 0 . E.).
long di stance bombardment or reconnaissance airplane. M. I. D. 2081-432.
France 6658-\V. January 25, 1923. 3 p. Photographs.
Service report on the Hanriot HD27 monoplace pursuit shipboard type
airplane. M . I. D. 20Sl-426. France 6607-\V. January 26, 1923. 2 p.
Photographs.
Martin.
Catalogue of Martin bomber, MB2; compiled by Property Maintenance
and Cost Compilation Dept. Fairfield Air Intermediate Depot. Nov., 1921.
Orenco.
Catalogue of Orenco D airplane ; compiled by Property Maintcnace and
Cost Con1pilation Dept. Fairfield Air Intermediate Depot. Dec. 1921. 62 p.
S E-5.
Catalogue of S. E. 5 airplane : compiled by Property Maintenance and
Cost Compilation Dept. Fairfield Air Intermediate Depot. Dec., 192 1. 171 p.
Wihault.
Service report on the \i\Tiba11lt experimental aircraft. M . I. D. 2081-
438. France 6643-W. Jan. 22, 1923. 2 p.
XB-lA.
Catalogue of XB-lA airplane; compiled by Property Maintenance and
Cost Compilation Dept. Fairfield Air Intermediate Depot. Dec., 1921.
149 p.
D52.l / 66
Curtiss
D52.l / 49
DH4
D52.l / l
G. A.-1
D52.l / 19
Hanriot
D52.l/ 21
Hanriot
D52.l / 17
Hanriot
D52.l/ 16
Hanriot
D52.1 / 18
Hanriot
D52.1/ 20
Hanriot
D52.1/24
Martin
D52.l / 17
Orenco
D52.l/38
S. E. 5
D52.1/5
Wibault
D52.l/ 10
U.S. X. B.1
NEW BOOKS AND DOCUMENTS
Helicopter.
Ceneral characteristics of the <le Bothezat helicopter; by Maj. A. H.
Hohley. Jan. 26, 1923. 2 p.
Tests with the captive helicopter; by Theodor Von Karman. Oct., 1918.
18 p. Photographs.
AIRCRAFT
(Lighter-than-air)
Maneuvering of airships; prepared under direction of the Chief of Air
Service. Training regulations 440-335. 1922. 10 p.
Erection and maintenance of airships; prepared 'under direction of the
Chief of Air Service. Training regulations. 440-220. 1922. 10 p.
Balloons.
Construction, maintenance, care and operation of balloons; prepared
under direction of the Chief of Air Service. Training Regulations 440-215.
1922. 33 p. Photographs, diags.
Maitenance and care of balloon accessories ; prepared under direction of
the Chief of Air Service. Training regulations No·. 440. 1922. 3 p.
Zodiac.
Service report of the Zodiac Vedette dirigible, 3800 cubic meters. M.
I. D. 2081-431. France 6656-W. Jan. 25, 1923. 2 p. Photostated drawings.
Zeppelin.
Nomenclature and drawings of the Zeppelin L49. In French. Oct. 20,
1917. Large document.
AERIAL NAVIGATION.
General.
Abstract of paper on air navigation; by R. W. \,Villson and M. D. Herey.
1922. 6 p.
International aerial traffic; by Capt. Hilderbrandt. Tr. from Koelnische
Zeitung, Jan. 8, 1922. M. I. D. Jan. 13, 1922. 4 p.
Beginning of a wiorld flight net; by R. Schnitzer; tr. from lllustrierte
Flug \i\Toche. Nov. 25, 1921. 6 p. Photostated map.
European air service net; by Maj. G. P. Neumann; tr. from lllustrierte
Flug-\Voche. May 25, 1921. 7 p. Photostated map.
Airways.
Agreement regarding London-Paris air route. M. I. D. England~13.
R-14112. June 28, 1922. 2 p.
Aerial traffic through the air port of LeBourget during the calendar year
1922. M. I. D. 2081-338/ 2. France 6620-W. Jan. 18, 1923. 2 p.
Al0.22/2
Bothezat
AI0.22/26
D52.7 / 12:-
DS2.1/ 126
D52.8/ 65
D52.83/46
D52.7 / 3
Zodiac
D52.7 / 12
Zeppelin
l\.40.3/17
Al0.01/33
Al0.01/34
Al0.01/35
A00.5/24
El0.2/29
29
30 T EC H N I CAL B U LL ET I N No. 33
Air Mail.
l\fonthly report of operation and maintenance of air mail service. United
States Post Office Dept. Aug. , 1922. Sept., 1922.
Consolidated statement of performance. United States Post Office Dept.
Air Mail Service. Fiscal year 1922. 2 p.
Air Stations.
The Airport- \Var Dept. 0. C. A. S. Feb. 18, 1922. 73 p. Photo­graphs,
drawings.
Contents:
1. Its necessity.
2. The landing facility.
3. Benefit to be derived from its establishment.
4. Appendix.
Notice of change of name of Columbus Barracks to Fort Hayes; Camp
Travis combined with Fort Sam Houston; change of name of Fort William
H. Seward to Chilkoot Barracks; designation of Santa Monica Airdrome and
Clover Field; announcement of assignments. 'vVar Dept. General orders No.
54. Dec.13, 1922. 2p.
Camp Eustis announced as a permanent military post. Designation of
Louisville airdrome. Col. C. C. Hammond placed on the general staff corps.
eligible li st. Discharge and appointment in the next lower grade of certain
majors, captains and first lieutenants. Battles and campaigns of the United
States. War Dept. General orders No. 1. Jan. 10, 1923. 3 p.
Night Flying, Aids to Navigation, etc.
Night air service; by Maj. Keller. Tr. from Der Lufturg. May 5, 1921.
5 p.
Hangars, landing fields, and mooring devices; prepared under the direc­tion
of the Chief of Air Service. War Dept. Training Regulations 440-265.
1922. 8p.
Specifications for installation of boundary lights at Columbus Airdrome.
Engineering Division. Air Senice. Feb. 8, 1923. 3 p. Diags.
Aerostatic tables. May l , 1920. 14 p.
Traffic Regulation.
Resolutions on airway rules adopted on the London-Paris air route. n. cl.
2 p.
French aerial tax law of Nov. 10, 1922; tr. from Revue juridique m­ternationale
de la Locomotion Aerienne. Feb. 6, 1923. 3 p.
Summary of civil aviation certificates and licenses issued , cancelled, re­newed
and still in force . . Canadian Air Force. Jan. 31, 1923. 9 p.
Statutory rules and orders, 1922, No. 650. Air Navigation Regula­tions,
1922, dated June 28, 1922, made by the Secretary of State for Air, for
the investigation of accidents, pursuant to section 12 of the air navigation
act. 1920 (10 and 11 Geo. 5, c 80) Air Mini stry. June 28, 1922. 7 p.
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Britain
XEW BOOKS AND DOCUMENTS
ARMAMENT.
Instructions for use of camera obscura for checking accuracy of shots
while training bombers. n. d. 5 p. Chart.
Handbook on Nelson mac hine gun synchronizer. Engineering Division.
Air Service. Nov., 1922. 34 p. Illus., drawings.
EQUIPMENT.
Electrical.
Electric wire and cable terminology. Bureau of Standards. Circular
No. 37. Eel. 2. Jan. 1, 1915.
Instruments.
Altitude effect on air speed indicators, II; by H. N. Eaton and W. A.
MacNair. National Advisory Committee for Aeronautics. Report No. 156.
Continuation of report No. 110. 1922. 46 p. Illus., charts, drawings.
Contents:
1. Experiments with venturi tubes.
2. Altitude correction.
Report on Bureau of Standards airspeed indicator, model 4, serial No.
404, developed for Engineering Division, U. S. Army Air Service. Bureau
of Standards. Feb. 6, 1923. Photographs, drawings, charts.
Report on installation of turn indicators for aircraft. Navy Dept.
Bureau of Aeronautics. Technical Order No. 25. February 10, 1923. 2 p.
Description of the Klemperer wing strain meter. n. cl. 3 p.
Royal Aircraft Establishment electrical indicator for high speed internal
combustion engines, also pressure gauge for maximum pressures; by H.
Wood. Aeronautical Research Committee. Reports and Memoranda No. 807.
(E. 5) I. C. E. 365. Apr., 1922. 12 p. , illus. charts, diags.
F urther tests of stellar radiometers and some measurements of plane­tary
radiation; by W. \V. Coblentz. Bureau of Standards. Scientific paper
No. 460. Dec. 23, 1922. 24 p.
Parachutes.
Report on parachute tests ; by C. C. Westorvelt. Naval Aircraft Fac­tory.
Aug. 7, 1922. 8 p.
FUELS AND LUBRICANTS.
Data on oils, giving manufacturer, brand and grade, gravity, flash fire,
pour test and clemulsibility. Bureau of Standards. 1919. 1 p.
MATERIALS.
General.
Fire tests of building columns ; S. M. Ingberg. Bureau of Standards.
Technologic Papers No. 184. April 21, 1921. 375 p. photographs, drawings,
charts.
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Indicator
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Air Speed
Indicator
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Turn
Indicator
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Wing. Strainer
Indicator
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R.&M.
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Radiometer
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32 T E C H N I C A L B U L L E T I N N o. 33
Strength and other properties of concrete as affected by materials and
methods of preparation; by R. J. Wig and others. Bureau of Standards.
Technologic Papers No. 58. June 20, 1916. 172 p. Photographs, draings,
charts.
Pouring and pressure tests of concrete; by W. A. Slater and A. T. Gold­beck.
Bureau of Standards. Technologic Papers No. 175. October 11 , 1920.
13 p. Drawings, photographs, charts.
Test of bond resistance between concrete and steel; by W. A. Slater and
others. Bureau of Standards. Technologic Papers No. 173. Nov. 1, 1920.
66 p. Photographs, drawings, charts.
Effects of "cal" as an accelerator of the hardening of Portland cement
mixtures; by R. N. Young. Bureau of Standards. Technologic Papers No.
174. Oct. 11, 1920. 24 p.
Test of a hollow tile and concrete slab reinforced in two directions; by
W. A. Slater and others. Bureau of Standards. Technologic Papers No.
220. Nov. 15, 1922. 66 p. Photographs, charts.
Compressive strength of large brick piers; by J. G. Bragg. Bureau of
Standards. Technologic Papers No. 111. Sept. 20, 1918. 39 p. Photo­graphs,
drawings, charts.
Durability of stucco and plaster construction; by R. J. Wig and others.
Bureau of Standards. Technologic Papers No. 70. Jan. 31, 1917. 74 p.
Photographs, drawings.
Report on colored wall plaster; by W. E . Enley and C. F . Faxon. Bureau
of Standards. Technologic Papers No. 181. Dec. 15, 1920. 8 p. Photo­graphs.
Dopes, Paints, Coatings.
Effect of various coatings and combinations of coatings of zaponite ( Dope
lacquer) and spar varnish upon the resistance to moisture penetration; by
A. C. Zimmerman. Material Section. McCook Field. Feb. 27, 1923. 4 p.
Test of Phoenix fireproof elope. Royal Aircraft Establishment report.
H. C. 695. n. cl. 5 p. Chart.
Fabric.
Methods of attachment of fabric to ribs on some German airplanes.
Royal Aircraft Establishment report H. C. 698. Aug. 9, 1922. 2 p. Photo­stats.
Gases.
Bibliography of scientific literature relating to helium. Bureau of Stan­dards.
Circular No. 81. Ed. 2. Dec. 21, 1922.
Rubber.
Effect of temperature and time on rubber shock absorber cord. Royal
Aircraft Establishment report M. T. 3498. July 24, 1922. 5 p. Charts.
. Data from recent samples of rubber shock absorber cord. Royal Air­craft
Establishment report M. T . 3743. Ang. 11, 1923. 3 p. Charts.
Metals.
Constitution and metallography of aluminum and its light alloys with
copper and with magnesium; by P. D. Meri.ca and others. Burfau of Stan­dards.
Scientific paper No. 337. Aug. 16, 1919. 15 p. Illus.
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{
I ,
I
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C
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NEW BOOKS AND DOCUMENTS
Report on "Bulldog" welding metal, submitted by Marshall Metal Cor­poration,
Chicago, Ill. ; by Samuel Daniels. Material Section. McCook
Field. Feb. 8, 1923. 6 p. Photograph.
Preparation and properties of pure iron alloys; II Magnetic properties of
iron-carbon alloys as affected by heat treatment and carbon content; by W. L.
Cheney. Bureau of Standards. Scientific paper No. 463. Dec. 27, 1922.
27 p. Illus., charts.
Wood.
Effect of Su-des process of treatment on physical properties of seevral
woods. Bureau of Standards. Letter circular LC-53. Nov. 28, 1922, 8 p.
Report on wooden specimens from France Field, Panama and static tests
DeHaviland 4 wing cellule; by R. L. Hankinson. Feb. 9, 1923. 5 p. Photo­graphs.
PHOTOGRAPHY.
Various photo-electrical investigations; by W. 'vV. Coblantz. Bureau of
Standards. Scientific paper No. 462. Dec. 20, 1922. 22 p. Charts.
POWER PLANTS.
General.
Air consumption and B. H. P. of aero engines; by H. Moss. Aeronatt­ticai
Research Committee. Reports and 11emoranda No. 798. (E. 3). I.
C. E. 364. Mar., 1922. 19 p. Illus., charts, diags.
Results of experimental flights at high altitudes with Daimler, Bentz and
:VIaybach engines, to determine mixtnre formation and heat utilization of
fuel; by K. Kutzbach. Tr. from Technische Berichte, Vol. 3, Part 1, Na­tional
Advisory Committee for Aeronautics. Technical notes No. 125. Jat:.
1923. 11 p. Charts.
Basse-Selve.
Tests of 6-cylinder, 270 H. P. Basse-Selve water-cooled engine, Royal
Aircraft Establishment report E. 1593. Sept. 26, 1922. 5 p. Charts.
Benz.
Tests of the 2-cylinder, 500 H. P. Benz engine, type B. Z. 6. Royal
Aircraft Establishment report E. 1586. Mar. 29, 1922. 5 p. Charts.
Curtiss.
Catalogue of Curtiss OX5 engine; compiled by Property Maintenance
and Cost Compilation Dept., Fairfield, Air Intermediate Depot. Nov., 1921.
18 p.
Diesel.
Diesel cycle and the aviation engine; by Dumanois. Tr. from the French.
National Advisory Committee for Aeronauti cs. n. cl. 25 p.
Hinkley.
Information and log sheets for Hinkley engme. Feb. 161 1923. 7 p.
Charts, blueprints.
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R. & M.
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Benz
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Curtiss
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Diesel
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Hinkley
33
34 T E C H N I C A L B U L L E T I N N o. 33
Jupiter, Jaguar, Lynx and Ounce.
Information on the Jupiter, Jaguar, Lynx and Ounce engines. M. I. D.
300-B-30/7. England 14917. G-2. Jan. 30, 1923. 3 p. Drawing.
Lawrence.
Endurance run of the Lawrence J 1, 9-cylinder air-cooled engine, serial
No. 9727, manufacturers No. 95. U. S. N. contract No. 56043. Lawrence
Aero Engine Corporation. Dec. 23, 1922. 48 p., photographs, charts.
Rapp.
Tests of 6-cylinder, 175 H. P. Rapp engine, No. 482. Royal Aircraft
Establishment report E. 1589. Aug. 31, 1922. 3 p. P hotographs, charts.
Salmson.
Characteristics of the Salmson radial engine CM 9 . n . cl. 1 p. Photo­graph.
Siemens.
Directions for operating, assembling and adjustment of 160 H. P. Sie­mens
engine, type SH3. N. cl. 12 p . Photostatecl drawings.
Wright.
Catalogue of \Vright engin e, model H-2; compiled by Property Main­tenance
and Cost Compilation Dept. Fairfield, Air Intermediate Depot. Dec ..
1921. 18 p.
Catalogue of \Vright H-3 engine; compiled by Property Maintenance
and Cost Compilation Dept. Fairfiield Air Intermediate Dept. Dec., 1921.
18 p.
Fuel Systems.
Solid connections in fuel and oil lines. Navv Dept. Bureau of Aero­nautics.
Technical order No. 24. Feb. 1, 1923. 2 p.
Starters.
Description and operation of the Herzmark starter, type A. V., for air­craft
engines. In French with translation. n. cl. 2 p. Illus.
Service report on the Verville airplane engine starter. M. I. D. 2081-
434. France 6691-V\T. January 29, 1923. 2 p. Photographs.
PROPELLERS.
Humidifying apparatus for propeller carving room at McCook Field;
by M.A. Smith, Jr. Airplane Section. McCook Field. Feb. 7, 1923. 5 p.
Diags.
Air propeller, its strength and correct shape; by H. Dietsus. Tr. from
Technische Berichte. Vol. III, part 2. National Advisorv Committee frJr
Aeronautics. Technical notes No. i27. 9 p. Charts. -
D52.41/32
Misc.
British
D52.41/3
Lawrence
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Rapp
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Salmson
D52.41 / 2
Siemens
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Wright
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Wright
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