On Wednesday, October 29, 2014, I watched a NOVA
presentation First Air War on PBS
Ch-13. The program described the
introduction and use of flimsy wood and fabric aircraft during World War – I
for scouting and later, combats. For the
interested viewer, the program may be viewed from PBS NOVA archives. Viewing this program stimulated my memory
enough to prepare this essay which follows.
When the Wright brothers created their airplane it was hardly more than an expensive kite. After perfecting a later model, they approached the U.S. Army for a possible manufacturing contract, but were turned down. After a number of negative experiences with foreign governments, they were able to convince the U.S. Army Signal Corps in 1908 to contract for one aircraft at $25,000 having a flying speed of 40 mph with the further stipulations that slower speeds achieved would reduce the contract price appropriately.
With the outbreak of WW-I in 1914, the participants had some
early aircraft models suitable for scouting and little else. With the incentive of war requirements,
aircraft designs moved forward rapidly with more sophisticated designs and
speeds of 80+ mph. When the United
States entered WW-I in 1917, it had few pilots and fewer aircraft forcing them
to purchase aircraft and training from the French.
In less than a year the aircraft of the warring nations had developed significantly. Another year found the aircraft actively firing on each other and the troops in the trenches.
Typical of later model planes were the British SE-5 (Top), the German Fokker Triplane (Middle) and the French Nieuport (Bottom)
When the war ended the U.S. had a surplus of
training “Jennies” and pilots who were willing to purchase the airplanes at bargain
prices to tour the countryside giving rides, doing wing-walks and stunts and
taking part in air shows.
I was born in 1922 at the end of this hoopla.
When NAZI Germany attacked Poland
on September 1, 1939, they employed Stuka dive bombers whose design and
efficiency violated post WW-I treaties and exceeded that of all other aircraft
at the time. I had graduated high
school and was working at Chance-Vought Aircraft in Stratford,
Connecticut. By the end of 1940, I was
convinced that the United States would be drawn into the fray, quit my job and
joined the U.S. Marine Corps. I was called
up in July 1941, completed boot camp and, in the fall, ordered to the NAS at
Jacksonville, Florida for training as an aircraft mechanic. At the time, the United States still had many
bi-wing aircraft constructed of wood and fabric plus some monoplanes of mixed
metal, wood and fabric construction. So,
training was varied and extensive in several fields.
Woodworking of wings and fuselage
was usually of Spruce formed by hand and steam to the proper shape. Fuselage members were rounded on top and
usually flat or near flat on both sides and bottom. A number of these members of different sizes
formed the length of the fuselage from the engine fire wall to the tail where
the empennage was attached. Connecting
these forming members were long pieces of wood, called stringers. In constructing the fuselage, the shaping
members were spaced apart and held in place by the stringers. Fasteners and glue held the stringers to the
shaping members with openings for cockpits and storage compartments. Seats, instrument panels and other required
parts were added before covering with fabric.
Trim followed.
The wings and empennage were of
similar construction and were usually fabricated at the same time. Wing shaping members called ribs were
fabricated of wood, usually Spruce, and shaped by hand and steam. The upper camber of the rib provided the lift
needed by the plane; the lower camber provided support. When constructed, the required number of ribs
was spaced out on a long table and connected by a strong stringer at the nose
of the rib. The tails of the ribs were
connected by a stringer of lighter construction, leaving room for the ailerons
which help control the roll of the plane.
Each wing tip had a formed curved member which connected the nose and tail
stringers. In overall construction, the
upper wing was one long wing evenly spaced over the fuselage. The lower wing was in two parts, each half
connected to the fuselage before the pilot’s seat. Wood struts connected the bottom of the top
wing with the top of the bottom wing.
Usually, the center of the bottom of the upper wing was fastened to the
top of the fuselage before the pilot with two or four struts.
The weight of the wings was
carried while the plane was on the ground by a set of shaped wires called
landing wires. When the plane was flying
the wings were supported by a set of shaped wires called fly-ing wires. These two sets of wires crisscrossed in the
space between the two wings.
After the wings and empennage
woodwork was completed the structure would be placed on a large table and
covered with one piece of linen cloth that wrapped both sides such that the two
edges of the cloth came together at the trailing edge of the wing plus some
extra cloth. The cloth was pulled tight
and pinned for the length of the trailing edge and wing tip. The resultant case was slid off the wing and
removed to an area devoted to machine sewing where all pinned cloth was sewed
by machine operators using a French Fell for the stitching. Surplus cloth was trimmed from the case, the
case was turned inside-out and returned to the wing where it was slid on the
structure and pulled tight. A large team
of stitchers would descend on the wing
with curved needles and linen thread and, complying with the specifications,
stitch the linen covering to each wing rib from the wing tip, starting at the
top of the wing and completing at the bottom.
Stitching specifications would instruct on the weight of the linen
thread, the number of stiches per camber and the type and number of knots per
camber. The stitched wing would then be
removed to an enclosed, ventilated area for painting.
The paint used was called “dope,” a
term that is still used for painting today’s fabric covered aircraft, but here’s
where my memory fails me. Today’s dope is
usually nitrocellulose, cellulose acetate or cellulose acetate butyrate. Whether or not today’s dopes and those used
during the early days of WW –II and the preceding decades are one and the same,
is not clear to me, but since the doping agents used during both periods were
used for the same purpose, it seems likely that they are the same. Dope is a plasticized lacquer. It is flexible and light, properties favored
by aviation enthusiasts who are attempting to keep weight down. It also is air tight and weatherproof. A major property of dope is its ability to
tighten and stiffen the fabric when applied properly. But, it has its problems. It is highly flammable and nitrocellulose,
being known in other quarters as gun cotton, is a substance used to fire heavy
caliber artillery. Despite the risks,
dope is still favored over other agents.
Dope, thinned, was applied with a
brush for two consecutive coats. Tape,
friction patches and any other patches added to protect against wear were cut
to size, given two coats of thinned dope and put aside to dry. The dope prepared tapes and patches were
moistened on the underside with dope and applied to the chosen areas. Before they dried another brush coat of dope,
not thinned, was applied. Here too my
memory fails me. Several coats of dope
were applied, I’m not certain how many.
Before war started for the U.S.,
the country was already at work on designs of new combat aircraft, few of which
were available at war’s start. Some
hybrid designs, monoplanes of metal construction with much of the plane still
fabric covered. One such plane was the
Vought Vindicator SB2U used by Marine squadrons. When Germany attacked Poland, the Vindicator
was already considered obsolete and the U.S. was at work rushing to replace the
Vindicator with a new dive bomber, the Douglas Dauntless SBD.
At the battle of Midway Islands in 1942, the Marines
operated both aircraft, but mostly Vindicators, losing all to the Japanese
fighter pilots.
The Vought Vindicator was of metal construction from the engine compartment back to a space on the fuselage halfway between the pilot and gunner. From that point on to the tail, the plane was fabric covered as were all control surfaces. The wing was metal covered, but the ailerons were fabric covered. The photos that follow show Vindicators in flight with pre-war markings.
The SB2U was the last combat plane that I saw with fabric
construction. Later during 1942 when I
was ordered to Samoa, I found an old bi-wing fighter plane that apparently was
abandoned by the U.S. before war broke out.
It had been appropriated by our commanding officer, refurbished and was
flown on occasion for pleasure. I doubt
if another such plane existed except possibly in a museum.
Those old bi-wing fighters were the end of a line of fabric
covered aircraft dating back to the First World War and except for
reconstructed craft, such as those fabricated and flown by the New Zealanders
of the NOVA program; we shall never see them again. For the aviation enthusiast, they will be
missed.
November 2014
LFC
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