Category And Colors

Eglin Field prepared a long and detailed report on the principles applicable to the camouflage of aircraft in flight. This stated that there were four fundamental variables in the perception of any visual object, – (1) size, (2) contrast with background, (3) illumination, and (4) duration of observation. The only one of these that could be controlled to any extent for the camouflage of aircraft in flight was the contrast of the airplane with the background. Camouflage was obviously a protection to a plane only when it could not be seen; success

of camouflage in flight was achieved, if when at the distance at which it would normally be visible, it still could not be seen. The report discussed camouflage of the various sections of the plane as top, side, and bottom surfaces plus various types such as sea search, night, gloss, confusion and temporary camouflage, plus that for photographic reconnaissance aircraft.

Camouflage could affect the performance of aircraft in two ways; by the increased weight of the paint and by increased drag if the paint was rough. In a generalized aircraft camouflage evaluation, the report stated that (1) top surface camouflage was very effective, (2) side and under surface average camouflage was of doubtful value.

It concluded that camouflage should be weighed solely on its merits of concealment. If camouflage was needed and was proven, opera­tional efficiency need not be sacrificed. If aircraft were required for special purposes where the operational altitude remained reasonably constant and operational conditions similar, camouflage could be selected which was effective and worthwhile. The report included a bibliography containing twenty-nine documents pertinent to the subject, including eighteen final reports issued by Egltn Field in 1942 and 1943.

Material Command initiates use of gloss black camouflage paint, January 12, 1944.

Material Command requested on January 12, 1944, that Production Division order all night fighter aircraft in production (P-61 and P-70) to be camouflaged with gioss black paint; this order superseded all previous orders for the camouflage of night fighters.

1, Thoroughly agitate the remover. Using a round bristle brush 6 to 8 inches in diameter with a 6-foot handle, apply a generous coating of the remover to areas being stripped. The remover should not be applied to surfaces which have water on them as water will stop the solvent action. It is best to strip the aircraft in sections, cleaning each section completely before going on to the next. The following order is recommended:

a. Tail section and fuselage aft of the trailing edge of the wing, including the empennage and tail cone.

b. Upper surfaces of the fuselage in the area of the wing and the complete fuselage and nose section forward of the leading edge of the wings.

c. Individual wings, upper and lower surfaces,, including the nacelles.

d. Remaining lower surfaces of the fuselage and miscellaneous removed parts such as the anti-drag rings.

2. After the first coat of remover has remained on the surface from 15 minutes to 1 hour, apply a second coat. In applying the stripper and in washing it off with water, use care to prevent excessive contact of the stripper with the masking material which is effective only as a protection against splashing and contact with small quantities of stripper. The stripper should not remain on the masking paper longer than 30 minutes without being washed off with water.

3, After the second coat of remover has remained on the surface from 15 to 30 minutes, scrub the wet surface thoroughly (using the same round bristle brush ) to loosen the finish that may not be entirely free of the metal. If the finish will not loosen, apply another coat of remover, allow to stand, and scrub again. The resistance to the remover of primed and camouflaged surfaces differs according to the initial finishing material used and the service the painted surface has had. The number of applications of remover and the scrubbing necessary to loosen the finish may best be determined by trial.

4. When the finish has thoroughly loosened, remove the finish beginning on the top surfaces, using a bristle brush push broom and water spray. A satisfactory water spray may be obtained by using a garden hose with the nozzle adjusted to a fine spray. The spray should give a generous amount of water at low or medium pressure and should be directed into the push broom which

should be about 18 or 20 inches wide. Do not apply water to the remover until loosening is complete, since water stops the solvent action of the remover.

When the surface has been thoroughly scrubbed, increase the pressure and volume of the water and thoroughly rinse the surface. Final Clean-up

1, Remove the masking material and clean the areas underneath by carefully applying remover with a paint brush. After the finish has softened, remove the major portion with Plexiglas, fiber, or hard rubber scrapers.

2. Prepare a mixture of approximately 3 parts of water with 1 part of ethyl acetate or 1 part of dope and lacquer thinner. Wash the entire stripped surface with soft, clean rags dipped in the mixture. Follow immediately by wiping dry with clean cloths. Best

North American P-51D-5-NA, 4-4-13396, aircraft GQ-G “One Long Hop”, of the 355th FS, 354th FG, seen at strip A-64 on October 8,1944. Note how the invasion stripes have been painted out with olive drab both above and below. The spinner is blue and checks on the nose are white and yellow. (William L. Swisher)

Martin B-26G-5-MA, 43-34258, in natural metal Finish, is yellow 06 of the 441st BS, 320lh BG, Italy. The lead aircraft is in Dark Olive Drab and Neutral Gray. All aircraft have red cowls and propeller bosses, Second natural metal aircraft is yellow 04 and the other is yellow 20. All are in the 441st BS. (USAF via Gerry R. Markgraf)

results are obtained when the final wiping operation is accomplished while the surface is wet with the mixture of water and thinner.

3. Blow out all seams on the wing, empennage, and fuselage. Clean out any stripper which may have run down inside the fuselage. Check the inside of the fuselage to be sure that none of the fluid has run through the seams onto vital parts.

4. Wipe up any miscellaneous deposits of remover on unpainted areas with rags dipped in the water-thinner mixture.

In addition to the standard painting requirements, all aircraft that are engaged in Air Sea Rescue Operations will have the following markings applied, using Specification No. AN-E-3 orange-yellow enamel and Specification No. AN-TT-E-501 black enamel. The markings given herein are applicable to large seaplanes and amphibians. On other aircraft the markings used will be those outlined herein as applicable to the shape, and appropriate to the size of the aircraft. Air sea rescue identification numerals and letters will be as assigned by Headquarters AAE

a. WING TIPS.

(1) Wingtip floats and struts will be painted with orange-yellow enamel, Specification No. AN-E-3, stock No.

7300-422000.

(2) Upper and lower surfaces of both wing tips will be painted orange-yellow from wing tip inboard a dis­tance 7 percent of the wing span (float excluded). A black border 6 inches wide will be added inboard, using Specification No. AN-TT-E-501 enamel, stock No. 7300-406000.

b. WING, CENTER SECTION, UPPER SURFACE ONLY.

(1) The upper surface of the center section, including rear projecting portion of the engine nacelles, will be painted orange-yellow to a distance just outboard of the two inboard engine nacelles. A black border 6 inches wide will be added outboard,

(2) On upper surface the word “RESCUE” will be superimposed in black. Centered aft of the word “RES CUE” the appropriate identification numerals and/or letters will be added. Letters and numerals will be of the modified vertical block type, uniform in shape and size, 36 inches high, 27 inches wide and the width of the individual strokes forming them will be 6 inches. Spacing between letters will be 12 inches.

c. REAR HULL (OR FUSELAGE).

(1) A36-inch orange-yellow band approximately 3 feet forward of the leading edge of the horizontal stabilizer will encircle the aft portion of the hull but not extend onto the last step of keel. Two 6-inch black stripes will be added as bor­ders

(2) On each side of the forward part of the hull or fuselage and centered between the leading edge of the wing and the bow, an orange-yellow rectangle, whose length shall be equal to three times its height will be painted. A 2-inch black stripe will be 33 percent ofthe vertical dimension of the projection of the fuselage side at the point of application except that the height of this rectangle will not be greater than 36, nor less than 20 inches, excluding the border. The national aircraft insignia, which normally would occupy this space, will be relocated aft on the hull to clear this marking

(3) “THE AIR SEA RESCUE” identification numbers and or letters will be superimposed in black, centered within the rectangle. These will be of the modified vertical block type, uniform in shape and size; and will be approximately two-thirds of the height of the orange-yellow rectangle. The width of the letters and numerals will be three-fourths of the height, and the width of the individual strokes forming them will be one-sixth of the height.

d. HULL (OR FUSELAGE) BOTTOMS.

(1) On the bottom of the hull, between the bow and the main step and extending from chine to chine, the air sea rescue identification numerals and/or letters will be painted. The top of the letters and/or numerals will be at the left-hand chine of the hull. Letters and numerals will be orange-yellow, bordered by a 2-inch black stripe.

(2) These letters and numerals will be three fourths as wide as high, the individual strokes forming them will be one-sixth of the height. Letters will be appropriately spaced.

15. HELICOPTER BLADE CLASSIFICATION NUMBERS.

Helicopter rotor blade classification numbers will be stenciled on the blade by any facility authorized to balance or alter the blade. This number will consist of three parts: first section will be the weight in pounds of the blade expressed in decimal form; the second number will be the distance in inches from the tip of the blade to the center of gravity of the blade; the third number will be the distance in inches from the leading edge of the blade to the center of gravity of the blade chordwise. Ex­ample: 57.2 – 126.3 – 5.2 when the blade has a weight of 57.2 pounds with center of gravity 126.3 inches from the tip of blade, and with the chordwise center of gravity 5.2 inches from leading edge. Stenciling, approximately 3/4 inch in height, will be accomplished with yellow dope.

SECTION IV

INSIGNIA

Under para. 5., T. O. 07-1-1 called out Spec. Nos. 98-24105 and 99-2050 for airplanes and lighter-than aircraft, respectively. Spec. 99­2050 will not be covered here as the AAF had no airships and very few balloons of any kind at this time. Interested readers will find full details of this spec, in the author’s work on the Air Service and Air Corps.

Spec. 98-24105-P was the current version of the spec., entitled “Marking for Airplanes and Airplane Parts”, issued on August 11,

1936. It covered very extensive requirements for markings on external and internal surfaces and parts of all airplanes. These included:

(1) Name plate to be placed in each airplane

(2) Serial number of the airplane

(3) Letters and numbers designating the manufacturer of the airplane

(4) Code markings giving a record of the materials used in the finish

(5) Date of manufacture of covered airfoils (fabric covered – author)

(6) Strut numbers

(7) Data card

The Douglas XB-19 was quickly camouflaged al the end of 1941, prior to flying to Wright Field on January 23, 1942. It was to be the largest aircraft ever to be Finished in dark olive drab and neutral gray. (Harry Gann)

Bell Airacobra Mk 1, AH621, in flight, shows how the Sky underneath has been brought too far up on the fuselage sides. (USAF via Gerry R. Markgraf)

Consolidated Model 32 Liberator II was one of 165 to be ordered by the RAF, with RAF serial numbers AL503/667. Ninety two of them were transferred to the Air Corps and used on the first trans-Atlantic transport service. Finished in the standard RAF night bomber scheme of dark green and dark earth on upper surfaces and night (black) on lower surfaces. It carries the Air Corps Ferry Command insignia on the rear fuselage. The USA flags denoted its neutral status. The number “76” on the fin is a shortened form of the RAF serial number, AL576. (USAF)

The following paragraphs cover the main external markings required on all AAF aircraft:

A. Color and style of markings. – Arabic numerals and letters made with black dope or black color-in-oil were to be used. Where black would not provide sufficient contrast, white was to be used.

B. Fuselage Markings – The following technical legend was to be stenciled on the left side of the fuselage, forward of the front cockpit. If the cockpit was in the nose of the fuselage, the markings were to be placed to the rear of the cockpit.

U. S. ARMY – {model designation)

AIR CORPS SERIAL No…………….

Crew Weight….. …..lbs.

The letters and numbers for the first two lines were to be not less than 3/4 inch, nor more than 1 inch high. All other lettering was not to be less than 7/16 inch high, nor more than 1/2 high.

C. Lower Wing Markings – the marking “U. S.ARMY" was to be painted on the lower surface of the lower wing or on the lower surface of the wings of monoplanes. The letters “U. S.” were to be painted on the right wing, and the word “ARMY" was to be painted on the left wing, with the top of the letters toward the leading edge of the wing. These markings were to be centrally located with respect to the wing outline. The letters were to be of the vertical type, 24 inches high and with strokes four inches wide.

No substantial changes in these marking requirements occurred until camouflage was called out for all combat aircraft in Spec. 24114, “Camouflage Finishes for Aircraft”, dated October 22, 1940. Their markings were to conform to Spec. 98-24105-P and amendments, except that the marking “U. S. ARMY” on the under surface of the wing was to be applied with blue, Shade 47 of Bulletin No. 41. All other exterior markings were to be applied with either red, black or blue, Shades 45, 44 and 47 of Bulletin No. 41.

This new release of the markings spec, grew to no less than twelve pages in length. The revisions included those for camouflage markings and were as follows:

All exterior markings on aircraft with camouflage finishes were to be applied with either red, black, or blue, shades Nos. 45,44, and 47 respectively, of Bulletin No. 41, of the same materials as the finish on the airplane.

Lower Wing Markings required that the marking “U. S.ARMY” was to be painted on the lower surface of the lower wing of biplanes or on the lower surface of the wings of monoplanes, except when the airplane was camouflaged, in which case the marking was not to be used. The letters “U. S.” were to be painted on the right wing, and the word “ARMY” on the left wing, with the top of the letters toward the leading edge. These markings were to be centrally located with respect to the wing outline. The letters were to be of the vertical type, 24 inches high and with strokes four inches wide.

Vertical Tail Markings required that each airplane should have a radio call number painted on its vertical tail surfaces. The number was to consist of at least four numbers, to be determined as follows: The first number was to be the last number of the year in which the airplane was manufactured, and the remaining numbers were to consist of the serial number of the air plane, using zero where necessary between the year designated and the serial number to make four numbers.

Example No. 1. – The radio call number of an airplane manufactured in 1942, having serial number 42-5434, was to be

25434.

Example No. 2. – The radio call number of an airplane manufactured in 1942, having serial number 42-7, was to be

2007.

Aradio call number was to be placed on each side of the vertical tail surface. Where more than one vertical surface was used the call number was to appear on the left exposed side of the left hand surface, and the right exposed side of the right surface. Each numeral was to be of the block type, the width two-thirds of the height and the strokes approximately one inch wide for each six inches in height. The distance between the numerals was to be equal to one-half the width of a numeral. The actual size of the numerals was to be such that the call number would be readily discernible from a distance of approximately 150 yards.

Uncamouflaged airplanes were to have the number on the vertical stabilizer surface. For light colored backgrounds, the numbers were to be black, and for dark backgrounds, the numbers were to be orange-yellow to chip No. 5 of Spec. 3-1.

Camouflaged airplanes were to have the number across both the vertical stabilizer and the rudder surfaces. For light colored backgrounds, the numbers were to be black Shade 44, Bulletin No. 41. For dark backgrounds, the numbers were to be red or blue, color shades Nos. 45 or 47 of Bulletin No. 41.

In reply to the Eglin Field suggestion on March 16,1943, that a clear varnish could be used as a substitute for the neutral gray camouflage, Mat. Com. (WF) on April 30,1943, stated that the practical considerations outweighed the theoretical advantages. It might be possible to save weight using such a varnish, but there was a tendency in painting to apply heavier coats of clear finishes than colored ones. Actual production figures on paint usage indicated that the possible weight reduction was extremely small.

Curtiss P-40-CU, 39-174, was the 18th P-40 built, and had managed to survive until April 10, 1943, most recently in the training role. It still has the “U. S. ARMY” under the wings, despite this being deleted from all aircraft in October 1942. (CSAF)

Lockheed P-38F-LO, 41-2308, is seen in dark olive drab and neutral gray finish which appears to have been overpainted with haze paint on the upper surfaces. However, it is fully armed and carries two rear-sloping yellow command bands on the rear booms. (USAF via Gerry R. Markgraf)

If both clear and camouflaged surfaces were smooth, Mat. Com. doubted that there would be any advantage of the clear finish over the camouflage paint. Mat. Com. also doubted that the clear finish would provide the same protection against corrosion that provided by zinc chromate primer, and the drying time of the clear varnish was longer than that of the presently used camouflage finishes. Due to these and other reasons (unstated), Mat. Com. recommended that the use of clear varnish should be reconsidered.

On November 3, 1943, HQ. AAF sent the following message to the VIII Ar Force Service Command:

Approved policy on camouflage is quoted in substance as follows: “No requirement exists for camouflaging any AAF aircraft except Night Fighters.

Night Fighters shall be painted with non reflecting type camouflage paint.

Camouflage paint will be eliminated from all production AAF airplanes subsequently produced except Night Fighters.

Navy type aircraft will be accepted with Navy camouflage.

Camouflage may be removed from existing AAF airplanes at the option of the Theater Commander or Commanding General under whose jurisdiction such aircraft operate in accordance with technical instructions issued by Commanding General Air Service Command.

Future production aircraft which require painting such as fabricated of wood shall be painted with aluminated paint”.

Above policy in no way prohibits Theater Commander if he desires from (retaining-sic) aircraft camouflage.

Western Proc. Dist. informed that camouflage would be removed from P-38s and B-29s, November 16,1943.

On November 16,1943, the Prod. Eng. Sect. (WF), informed the Western Proc. Dist., Los Angeles, that camouflage would be removed in production from P-38 and B-29s, but not from other aircraft until the Army, Navy, and Lease-Lend recipients could reach an agreement.

Material Command on January 13, 1944, directed Douglas to proceed with the deletion of camouflage on A-20G, A-20H, A-20J, and A – 20K aircraft, in accordance with their earlier letter dated December 8,1943. They told Douglas that a contract change would be initiated when Douglas told them the effective point of the change, and requested that Douglas expedite comments and date of the effective point. On January 17, 1944, Douglas advised Material Command by teletype that immediate results could be obtained by refinishing A-20 series aircraft in an aluminum color, as outlined in AAF tetter dated December 8, 1943. They had been unable to find any satisfactory stripping material that would allow them to delete camouflage without causing serious production delays. They requested permission to produce bare-mctal A-20 series aircraft, as requested in the letter dated December 27, 1943. The Douglas letter dated January 8, 1944, made no mention of eliminating primer on A-20 aircraft. Douglas’s effective point was contingent on an answer to the letter of December 27,1943, and upon receipt of allocations for AAF P-70, Moth and Mink aircraft a minimum of three months in advance of delivery dates. This was so that Douglas could make satisfactory arrangements for the deletion of camouflage with subcontractors. They concluded by requesting authority to proceed signed by an AAF contracting officer.

On February 8, 1944, Douglas received an air mail letter from Material Command, which stated that this letter was to be considered the final directive, superceding the letter dated December 8, 1943, for the deletion of camouflage on A-20 series aircraft. Douglas was directed to take immediate action to delete all exterior camouflage from subject airplanes without causing a delay in production. It went on to direct that prior to delivery, all A-20 aircraft allocated to Mink, Moth and those destined for conversion to P-70 airplanes would be camouflaged on exterior surfaces only, in accordance with present camouflage schemes. A primer coat of zinc-chromate primer was required on Mink, Moth and P-70 aircraft. All A-20 series aircraft delivered to the AAF were to be delivered without camouflage and other exterior coatings, except for Moth, Mink and P-70 aircraft.

This exchange concluded that started on December 8,1943, and serves to show the reasons for some of the typical delays and misunder­standings that arose in implementing new AAF policies on the production lines.

In the same October copy of the service bulletin, Douglas detailed how to prevent corrosion of the wing and nacelle skins due to exhaust gases. This had been found prevalent due to these aircraft being delivered in natural metal finish, rather than camouflage finish. (This became a problem on most post war piston-engined commercial transports and resulted in extensive painting of the affected areas – author).

Skin Treatment

CORROSION OF WING AND NACELLE SKIN DUE TO EXHAUST GASES

Excessive corrosion of wing and nacelle skin surfaces due to exhaust gases has been found on C-54 series airplanes delivered with natural rather than camouflage finish.

To eliminate this corrosion, the following procedure is recommended:

1. Remove oil and dirt from areas affected by wiping with rags saturated with wash thinner or suitable solvent. Wipe the surfaces with dry rags before allowing the thinner or solvent to evaporate completely.

2. Prepare the affected area for painting by using either of two methods, depending upon the severity of the corrosion:

a. If the corrosion is light or moderate, polish with Bon Ami in the normal manner. Other abrasives may be used, but care should be taken to see that they are not too severe.

b. If the corrosion is severe, smooth the surface of the metal by means of an abrasive cloth or sandpaper (no. 280 to 400 grit). Apply a hydrofluoric acid-gum tragacanth solution (see NOTE) with a paint brush and continue brushing to aid the etch­ing action. When the surface and pitted areas appear clean, remove the gum-acid solution with damp rags, flush thoroughly with water, and wipe dry.

CAUTION: Goggles, rubber aprons, and rubber gloves should be used when the gumacid solution is applied. Short-time con tact with the acid is not harmful if the acid is rinsed off immediately with plenty of water. The acid should not come in contact with areas or parts, particularly plated steel, other than specified. The landing gear should be covered with paper during this cleaning.

North American P-51B, serial unknown, aircraft no.261, of the 26,h FS, 51я FG, at one of the Fourteenth Air Force South China airfields. It had to be evacuated on November 19,1944, in Ihe face of a strung Japanese offensive. Aircraft is in standard camouflage and has two yellow hands, trimmed in hlack on the vertical tail and yellow wing tips, possibly yellow. The sharks teeth nose marking is in black, white and red. (USAF)

After the surfaces are thoroughly cleaned, apply one spray coat of zine chromate primer (Spec. AN-TT-P-656) to affected areas and allow to dry. Apply two spray coats of aluminized lacquer over the primer surfaces.

NOTE: To prepare the aluminized lacquer, add 2 parts of lacquer thinner (Spec. AN-TT-T256) to 3 parts of Du Pont No, 1234 clear lacquer. Add 6 ounces of aluminum paste (Spec. AN-Tr-A-461) for each gallon of thinned lacquer. The procedure should be repeated when subsequent cleaning of the surface removes the aluminized lacquer to the extent that the zinc chromate primer is exposed.

Two Dark Olive Drab and Neutral Gray, and one natural metal Martin B-26, drop their bombs in Italy, late 1944. Nearest aircraft is B-26C-45- MO, 42-107531. All are from the 441st BS, 320th BG, as shown by the yellow aircraft tail numbers. (USAF’ via Gerry R. Markgraf)

Boeing B-29-10-BA, 42-63393, aircraft “I", named “B-13 Rush Order”, of Ihe 462nd BG,58th BW, Twentieth Air Force, seen in China late 1944. (USAF)

Aluminized lacquer will be applied to the exterior areas affected on C-54B airplane AAF 43-17150 and all subsequent prior to delivery. Starting with C-54B airplane AAF 43-17163, the interior surfaces of the trailing edge of the center wing will have two coats of aluminized A and A lacquer (Army Specification 3-168) applied over the zinc chromate primer coating in production.

Boeing B-29-15-BW, of the 678th BS, 444th BG, Twentieth Air Force, flying over the Himalayan Mountains enroute to Japan on November 21, 1944. The lead aircraft is 42-6399, and has the squadron unit insignia on its nose. All aircraft carried the large black diamond above the serial number on the tail; the aircraft no. in white signified the aircraft number in the group. No.34 leads nos. 44 and 55 in this photo. A large yellow band with black diagonal stripes, around the fuselage behind the wing, indicates the 678th BS. (USAF)

Six Martin B-26s, one camouflaged and the rest natural metal, of the 441st BS, 320th BG, over Italy in late 1944, The most distant natural metal aircraft has invasion stripes under the fuselage only, probably a replacement aircraft from England. (USAF via Gerry R. Markgraf)

Douglas C-47A-40-DC, 42-24051, aircraft CN-N of the 73rd TCS, 434th TCG, leads others from that unit and the 74th TCS, 434th TCG, Ninth Air Force. They are on their way to drop supplies to the beleaguered troops in Bastogne, Belgium, December23,1944, Note the external supplies on rack under the fuselage and wings of the aircraft. Invasion stripes remain only under the fuselage. The lead aircraft still carries the factory applied medium green blotches and dearly shows the repainted blue outline to the 1943 insignia. (USAF)

Republic P-47D-6-RE, 42-74742, aircraft WZ-D bar, “Snafu”, of the 84th FS, 78th FG, Eighth Air Force, is seen after a belly landing at Duxford in England on December 15,1944. Nose checks are black and white, the name and the 90 mission markers are in yellow, code fetters white as is the band across the fin. The rudder is black- Note the large rear view mirror above the front screen. (USAF)

Boeing B-17F-40-DL, 42-3236, aircraft PY-3236 of a training group, starting up. Note its two-color top camouflage. Behind it are five more fi­ns, one P-51A, one Curtiss P-40, three P-47s, one B-25, one B-24 and one A-34. Location unknown, but is a major base with acres of concrete ramp and runways.

The diameter of the insignia will be standard size which is nearest to, but not greater than, 75 percent of height of fuselage at the point of application except that night fighter aircraft will have 25-inch insignia. The diameter of the basic blue circle should be not less than 20 inches or greater than 50 inches. These will be placed and maintained on each side of the fuselage near midway between the trailing edge of the wing and leading edge of the horizontal stabilizer, but may be moved to the rear (or forward) of the midpoint to avoid turrets or other plastic material. The insignia may extend over doors and emer­gency exits, but shall not extend over windows or openings which would change the insignia pattern. If the fuselage section, as described herein, is not large enough to accommodate the minimum size specified, the fuselage insignia may be placed on such other parts of the fuselage as will permit its being readily seen from the side. On aircraft assigned to AAF Training Command, if insufficient space is available for both the insignia and Field identifying numerals, the fuselage insignia may be omitted.

17. ORGANIZATIONAL INSIGNIA

a. The placing of organization markings or design (approved by the War Department as outlined in AAF Regulation 35-22) will be the responsibility of the organization itself. Depots will not be required to reproduce this insignia.

b. No specific locations are mandatory, but points between wing and tail surfaces on opposite sides of the fuselage are considered most desirable. In no case will size of insignia exceed 75 percent of height of fuselage at point of application. Similar airplanes in the same organization will have the same size insignia. If applied to other than smooth surfaces, insignia may be painted on the aluminum sheet and bolted or screwed securely to rigid members of the airplane.