cockpits of transport planes the world over. The Sperry Gyropilot then
was perfected. This remarkable instrument, based on the gyroscope
movement, was developed actually to manipulate automatically the
controls of even the largest airplane, keeping it directly on the
desired course and leaving the human pilots free for their many other
duties.
In 1933, Wiley Post flew around the world alone, but the Gyropilot
piloted the _Winnie Mae_ over most of the route. This relieved the
fatigue of constant flying and allowed Wiley to keep a continual check
on his maps. His successful use of the automatic pilot soon caused its
adoption by most of the major airlines of the country.
Thus, with the aid of the radio beam, better flight instruments, special
octane gasoline, two-way radio, sound-proofing, wheel brakes, and
adjustable pitch propellers, the airlines of America were fast emerging
into a safe and comfortable means of travel.
While the DC-2 was coming into prominence in the air transport field,
Boeing engineers had gone on with their idea of a two-engined plane and
had built an all-metal bomber for the Army.
In building the two-engined, all-metal B-9, Boeing engineers learned how
to build another plane with a more peaceful purpose. This ship was the
famous Boeing 247-D commercial transport plane. The 247-D was an
all-metal, low-wing monoplane, powered with two 550-horsepower Pratt &
Whitney Wasp radial engines. It had a top speed of 200 miles per hour
and a cruising speed of 180 miles per hour. It was America’s first
three-mile-a-minute air transport plane.
In designing the speedy 247-D, the Boeing did not forget the comfort of
the passengers. The plane was fully heated and ventilated. Its seats
were deeply upholstered and had reclining backs. There were broad
windows at each chair. There were dome lights and individual reading
lamps; and the plane was equipped with a tiny galley and a complete
lavatory. Insulation kept the 247-D quiet and comfortable in any sort of
weather.
The 247-D carried ten passengers, a pilot, co-pilot, and stewardess,
plus baggage and mail. It was first put into service by the United Air
Lines in 1933, on their coast-to-coast route. Incidentally, it was
United who had introduced to the airlines the third member of the air
transport’s crew, the stewardess. The pretty young stewardesses were all
trained nurses. They looked after air-sick passengers, served food en
route, and looked after the comfort of the air travelers.
[Illustration: BOEING 247 TRANSPORT
POWERED WITH TWO 550-HP. PRATT & WHITNEY RADIAL ENGINES, THE 247
CRUISED AT 180 MILES PER HOUR. ITS TEN PASSENGERS RODE IN DEEPLY
CUSHIONED SEATS WITH RECLINING BACKS. ITS WELL-VENTILATED, HEATED
CABIN WAS SOUND-PROOFED TO DEADEN THE ROAR OF THE ENGINES, AND THE
PASSENGERS RODE IN QUIET COMFORT.]
LUXURY AIRLINERS AND SKYSLEEPERS MAKE AIR TRAVEL AN ACCEPTED FACT
With the Boeing 247’s, United Air Lines in 1933 cut the coast-to-coast
air trip to twenty-two hours. As DC-2’s and the fast two-engined
Lockheed _Electras_ were speeding up air transport schedules on the
airlines throughout the country, differences arose between the
government and some air transport firms over mail contracts. The result
was the cancellation in February, 1934, of all air mail contracts.
The air mail revenue was the life of the air transport operators and the
cancellation of the mail contracts suddenly darkened their future. An
attempt to put the transportation of air mail into the hands of the
United States Army resulted in a tragic failure. This was due mainly to
the unfamiliarity of Army pilots with air mail routes and their lack of
proper equipment. In June, 1934, the air mail was turned back to the
airlines.
The return of the air mail contracts to private operators saw the
introduction of the new Douglas DC-3. This was the plane that brought
Donald Douglas’ dream to complete fulfilment. His big, all-metal,
low-wing, two-engined DC-3 completely revolutionized air transport. By
1935, the name Douglas had come to mean fast, comfortable, and safe air
transport.
[Illustration: 1934-1940
WINGSPAN 95 FEET
LENGTH 64 FEET
THE DC-3, A LARGER AND MUCH IMPROVED VERSION OF THE DC-2, ACHIEVED
INSTANT POPULARITY ON ITS INTRODUCTION IN 1934.
POWER
TWO 9-CYLINDER 800-HP. RADIAL ENGINES
THE FIRST DC-3’S WERE POWERED WITH 800-HP. ENGINES, BUT LATER MODELS
USED RADIALS UP TO 1150 HORSEPOWER.
SPEED
ONE HOUR
180 MILES
THE DC-3 HAD A TOP SPEED OF 212 MILES PER HOUR, BUT ITS MOST PRACTICAL
CRUISING SPEED WAS 180 MILES PER HOUR.
RANGE
1680 MILES
ITS LONG CRUISING RANGE MADE IT POSSIBLE FOR THE DC-3 TO MAKE THE
COAST-TO-COAST TRIP WITH ONLY THREE STOPS.
CEILING
21,000 FEET
ITS MOST PRACTICAL ALTITUDE WAS FROM 8,000 TO 10,000 FEET, THOUGH THE
DC-3 WAS CAPABLE OF REACHING AN ALTITUDE OF OVER 21,000 FEET.
PAYLOAD
21 PASSENGERS
PLUS 2,000 POUNDS
OF MAIL AND CARGO.
THE DC-3 WAS STEAM-HEATED AND SOUND-PROOFING MADE IT AS QUIET AS A
PULLMAN CAR. IT WAS EQUIPPED WITH EVERY KNOWN SAFETY DEVICE.
NOW, THIRTY-ONE YEARS AFTER THE INVENTION OF THE AIRPLANE, WE BEGIN TO
SEE THE RESULTS OF THE EFFORTS OF AMERICAN ENGINEERS AND AIRCRAFT
BUILDERS. LIGHTWEIGHT, POWERFUL ENGINES; LIGHTWEIGHT, METAL
CONSTRUCTION; RETRACTABLE LANDING GEAR AND SAFETY DEVICES PLAYED A VITAL
PART IN MAKING THE DC-3 A SUCCESS.]
[Illustration]
The Douglas DC-3 was produced in 21-passenger day planes, 14-passenger
de luxe _Skylounges_, and 14-passenger _Skysleepers_. The DC-3 put
“sleeper planes” on an acceptable basis. Coast-to-coast schedules were
cut to three stops and an overnight trip. Fares were cut in half and air
travel became an accepted fact.
[Illustration: THE SIKORSKY S-42, PATHFINDER OF THE PACIFIC, HAD A
WINGSPAN OF 118 FEET AND WAS 64 FEET LONG.]
PAN AMERICAN CLIPPERS CONQUER PACIFIC SKIES
While the DC-3’s were cutting to an overnight hop the air journey from
coast to coast, Captain Eddie Rickenbacker had pushed his Eastern Air
Lines from New York to Miami, Florida. Here it connected with Juan
Trippe’s Pan American Airways. By this time Trippe’s Pan American
_Clipper_ planes regularly were covering a route from Miami down through
the West Indies to Rio de Janeiro, Brazil, and to Buenos Aires in the
Argentine. At Buenos Aires Pan American Airways connected with Harold R.
Harris’ Pan American-Grace Airways to complete a route over the Andes
and back up the west coast of South America.
The story of Harold Harris and his airway is a book in itself. Harris, a
veteran flier of World War I, had been an Army test pilot. In 1922 he
became the first member of the “Caterpillar Club” when he used a
parachute to escape from a plane which had failed. Later, as a
crop-dusting pilot in Peru, he visualized and founded the Pan
American-Grace air route.
By the time Juan Trippe’s Pan American Clippers were flying over every
country in Central and South America, his active mind was busy planning
another “survey.” Though his company at that time was operating the
world’s largest airline, Trippe was planning new worlds to conquer.
Pan American had been using Igor Sikorsky’s four-engined flying boats on
his route to Rio and Buenos Aires, and Trippe sent one of them, with
veteran Edwin Misick in command, on a “survey” flight westward across
the Pacific.
[Illustration: 1935
WINGSPAN 130 FEET
LENGTH 90 FEET
THE GIANT MARTIN 130 WAS DESIGNED AND BUILT FOR THE LONG-RANGE FLIGHTS
THAT WERE NECESSARY ON PAN AMERICAN’S TRANS-PACIFIC ROUTES.
POWER
FOUR 14-CYLINDER 750-HP. RADIAL ENGINES
IT WAS POWERED WITH PRATT & WHITNEY TWIN-ROW, WASP RADIAL ENGINES AND
HAD A TOP SPEED OF 180 MILES PER HOUR.
SPEED
ONE HOUR
130 MILES
RANGE
3,200 MILES
CEILING
10,000 FEET
PAYLOAD
46 DAY PASSENGERS
OR 26 SLEEPING
BERTHS, A CREW
OF SIX, AND A
TON OF MAIL
OR CARGO.
THE MARTIN 130, CALLED THE _CHINA CLIPPER_, WAS THE FIRST OF A GROUP OF
MARTIN FLYING BOATS THAT PIONEERED PAN AMERICAN’S TRANS-PACIFIC MAIL,
PASSENGER, AND CARGO SERVICE FROM AMERICA TO HAWAII, THE PHILIPPINES,
CHINA, AND AUSTRALIA. THE GIANT, ROOMY PLANE WAS EQUIPPED WITH EVERY
LUXURY FOR AIR TRAVELERS. IT COULD CLIMB TO AN ALTITUDE OF OVER 17,000
FEET, BUT CRUISED MORE ECONOMICALLY AND COMFORTABLY AT 10,000 FEET.
THE MARTIN 130 WAS THE LARGEST FLYING BOAT OF ITS TIME. IT WAS OF VERY
RUGGED CONSTRUCTION AND WAS EQUIPPED WITH TWO-WAY RADIO AND OTHER SAFETY
DEVICES. THE ORIGINAL _CHINA CLIPPER_ BUILT UP A RECORD OF 12,000,000
MILES OF OCEAN FLYING FROM 1935 TO 1945.]
[Illustration]
On November 22, 1935, Pan American Airways’ _China Clipper_ took off
from San Francisco Bay on its first scheduled trans-Pacific flight to
Manila, Philippine Islands. One hundred years before, to the day, the
first Yankee clipper ship had sailed into the same bay. Twenty-five
years before, a young man had made America’s first trans-Pacific
flight--a flight of 33 miles from the California shore to Catalina
Island. The 26-ton _China Clipper_ heading into its 8,000-mile
trans-Pacific flight was a Martin 130 flying boat built by Glenn L.
Martin, the young fellow of the Catalina flight. In just 59 hours and 48
minutes of flying time the first _China Clipper_ landed in Manila Bay.
PAN AMERICAN CLIPPER INAUGURATES AMERICA’S FIRST TRANSATLANTIC AIR
TRANSPORT SERVICE
With the sweep of its wings the first _China Clipper_ ripped out weeks
of slow surface travel to the rich markets of the Far East. By 1936 a
trip from this country to China was measured by a matter of sixty or
seventy flight hours instead of by weeks.
It was not the big clipper planes alone that built the far-flung Pan
American Airways. Juan Trippe visualized his world airways system and
then picked the finest experts in every field to carry out his plans.
Former diplomats covered the proposed routes long before the Clippers
flew them. There was, of course, no freedom of the air. No plane could
fly over a foreign country without permission. Trippe’s emissaries had
to get franchises. Germany, France, Britain, and Holland were after
franchises in South America too. There, as in the Far East, they got the
rights to fly, not by government pressure, but by selling aviation as a
valuable business asset to any nation.
Once Trippe had his franchises, he sent experts to explore and lay out
routes. They carved airports out of jungles and Arctic wastes, and in
places where no white man ever had penetrated. The supply problems
overcome and the engineering marvels performed by Trippe’s advance men
would furnish plots for a dozen movie thrillers. In laying out the bases
at Wake and Guam on the Pacific route, more than one million separate
items were bought, shipped, and installed before the first _China
Clipper_ took off from San Francisco.
Pan American’s map added another blue line after the Pacific route was
under way. This time it was to Alaska, and another distant travel time
could be reckoned in flight hours rather than ocean days.
Then came the Atlantic and the giant Boeing 314 Pan American _Clippers_.
[Illustration: 1939-1945
WINGSPAN 152 FEET
LENGTH 106 FEET
THE HUGE LONG-RANGE BOEING _CLIPPER_ WEIGHED 41-TONS.
POWER
FOUR 14-CYLINDER 1,500 HP. RADIAL ENGINES
FOUR 3-BLADED PROPELLERS WITH A DIAMETER OF 14 FEET FURNISHED THE
_THRUST_ FOR THE PLANE.
SPEED
ONE HOUR
175 MILES
RANGE
3,100 MILES
CEILING
15,000+ FEET
PAYLOAD
PAYLOAD
74 DAY
PASSENGERS.
OR 40 SLEEPER
PASSENGERS,
A CREW OF 8 TO
15 PLUS 2 TONS
OF MAIL
THE BOEING _CLIPPER_ HAD A TOP SPEED OF 190 MILES PER HOUR AND COULD FLY
NONSTOP FOR 3,100 MILES WITH 40 PASSENGERS. IT WAS OF ALL-METAL
CONSTRUCTION AND DIVIDED INTO ELEVEN SECTIONS BY BULKHEADS. IT HAD AN
UPPER DECK FOR THE FLIGHT CREW AND STORAGE SPACE. THE MAIN DECK WAS
DIVIDED INTO TEN COMPARTMENTS FOR PASSENGERS. BELOW THIS DECK WERE A
SERIES OF WATERTIGHT COMPARTMENTS. A PASSAGE THROUGH THE WINGS PERMITTED
THE SERVICING OF THE ENGINES DURING FLIGHT.
THE FIRST BOEING _CLIPPER_ TO SPAN THE ATLANTIC WAS THE LARGEST
COMMERCIAL AIRPLANE IN THE WORLD. THE _CLIPPER_ WAS EQUIPPED WITH EVERY
AVAILABLE SAFETY DEVICE AND LUXURIOUSLY FITTED FOR THE DAY AND NIGHT
COMFORT OF THE PASSENGERS. THE STURDY, SAFE _CLIPPERS_ OPENED A NEW ERA
OF AIR TRAVEL.]
[Illustration]
Boeing achieved such excellent results with its two-engined planes that
its engineers went on to plan four-engined super-planes. When Juan
Trippe wanted a plane for his Atlantic service, Boeing was ready with
the 41-ton Boeing 314. The 314 _Atlantic Clippers_ carried 74 passengers
and boasted of compartments that could be converted into berths,
dressing rooms, a dining salon, and a real kitchen for serving hot meals
aloft. On May 20, 1939, just twenty years after the first transatlantic
flight of the Navy NC’s, the _Atlantic Clipper_ took off on the trip
that inaugurated Pan American Airways service to Europe. Juan Trippe’s
dream was reaching around the world.
[Illustration]
PRIVATE PLANES
In the very early days of aviation, before the start of World War I,
most of the airplanes, with the exception of a few military ships, were
sold to private owners. Those buyers were either barnstormers or wealthy
sportsmen. Some advertising in national magazines even tried to create
sales, for private planes. This activity ceased with the beginning of
the war in 1914, and owners turned their planes over to the Government
for training purposes.
At the end of the war there were hundreds of young men who had learned
to fly. This situation brought about a considerable amount of private
flying. However, most of the ex-service men bought surplus war
equipment, such as the Curtiss _Jenny_, so that there was not a large
market for the manufacturers of new private planes.
Following the Lindbergh flight to Paris and other spectacular aviation
achievements, the American public really became air-conscious. It was at
that time that the private plane came into its own.
People began to find that airplanes were of practical value, and
business firms began to use them in various ways. Sales and service
representatives could cover vast areas in a short time. Essential
equipment could be carried swiftly by airplanes over stretches of
country which before had been almost inaccessible. Ranchers used planes
to cover far-flung ranges. Explorers and scientists alike used the
airplane to search for hidden treasure and precious minerals in spots
which before had been impossible to reach by land transportation.
All this activity brought about the development of more comfortable
cabin planes and led to a demand for large and small private ships. The
small, light plane field expanded with amazing speed once there was a
demand. In the late twenties Aëronca, Taylor, and Piper began to bring
out safe, comfortable, and inexpensive planes. By the middle thirties
flying schools and private landing fields were a common sight throughout
America.
As the light planes became popular, the training of private pilots
developed into a big business. Flying lessons became an important source
of income to aviators who heretofore had operated their little airfields
on the revenue derived from sightseeing hops and an occasional charter
trip. Student pilots became logical prospects for
[Illustration: PIPER _CUB_ TWO-PLACE PERSONAL LIGHT PLANE.
LAMINATED BIRCHWOOD PROPELLER
FOUR-CYLINDER AIR-COOLED ENGINE
METAL COWLING
DUAL CONTROLS
LANDING GEAR
METAL WHEEL “PANTS”
LIFT STRUTS
WELDED STEEL TUBE FUSELAGE FRAME
FABRIC FUSELAGE COVERING
TAIL WHEEL
RUDDER ELEVATOR
ALUMINUM RIBS
FABRIC COVERING
STABILIZER]
light planes and the more successful flying schools became sales
agencies for the aircraft manufacturers. Students became expert fliers
and graduated to instructors’ jobs. A number of these young instructors
in turn bought light planes and started flying schools of their own.
Thus, light plane flying spread like wildfire over the country.
The light planes of the late thirties were mainly high-wing monoplanes.
They were powered with light, air-cooled engines and were so designed
that they had a high factor of safety. They were sturdily built and easy
to fly. The average student was able to solo after eight or ten lessons,
though real flying ability came only through constant practice. Light
planes cost from $1,500 to $2,000. Many of them were equipped with
accessories such as heaters, radios, navigation lights, and flight
instruments. All of them had comfortably upholstered, enclosed cabins.
In the years just before World War II light plane flying for business
and pleasure was an accepted mode of travel for boys and girls as well
as men and women of all ages.
SUPERCHARGERS AND SUPER-AIRLINERS
High above the earth, 14,000 to 20,000 feet, lies a region of smooth air
called the substratosphere.
[Illustration: BOEING 307 _STRATOLINER_]
Pioneer fliers had reached this region years before, but its thin, rare
air made life and movement impossible. Men had long looked to this
smooth-air region as the ideal flight path--a path without rough air, or
fog, or storm to slow their progress. But both they and their engines
needed plenty of air for operation.
It was not until 1939, when Dr. Sanford Moss invented the
turbo-supercharger, that high engine performance at altitudes above
30,000 feet became a matter of fact. The turbo-supercharger, a simple
machine driven by the force of the engine exhausts, pumped air into the
engines to give them sea-level pressure at high altitudes. This took
care of the engines in the smooth-air substratosphere regions.
Next came the human element. Human beings, like engines, cannot live
without sufficient air. This brought about the development of the
supercharged cabin for airplanes. In 1936 “Tommy” Tomlinson, a brilliant
ex-Navy flier, started making experimental substratosphere flights for
TWA in a specially designed plane. He found that the speed of a properly
equipped airplane would increase some 36 per cent at 30,000 feet. At the
same time Army engineers were experimenting with a Lockheed plane having
a supercharged cabin.
The Boeing Company, working in co-operation with Tomlinson,
Transcontinental and Western Airways, and Pan American, developed the
Boeing 307. The 307 was a big all-metal, low-wing monoplane with a
pressurized, high-altitude cabin, which made possible flight at
altitudes up to 20,000 feet. This was accomplished in a manner similar
to that used in supercharging the engines. Engine-driven superchargers
pumped air into the cabin-ventilating system and the atmosphere in the
plane was kept at normal low-level pressure regardless of how high the
plane flew. The Boeing 307 _Stratoliner_ was put into service by TWA and
Pan American Airways in 1940 and marked a tremendous step forward in the
speed and comfort of modern air travel.
In 1941, fifteen years after the operation of the nation’s airlines had
been turned over to private firms, air transport was approaching
perfection. The first single-engined, two-passenger mail planes,
cruising at 100 miles per hour, took thirty-three hours to make the
coast-to-coast trip. Now giant luxury airliners were doing it in fifteen
hours. In contrast to the frequent stops of the low-flying plane of the
early days, the high-flying air transports of 1941 were making the
journey with only three stops. Where the air traveler of the twenties
rode in an uncomfortable seat in a cold, gas-smelling plane, and was
lucky if he got a box lunch, the modern passenger rode in luxuriously
upholstered chairs in a heated salon, and dined on hot fried chicken or
steak with all the “trimmings.”
Even more significant was the change in flight and safety aids. No
longer did the pilot fly with his eyes on the railroad tracks and the
family wash on the line below. Radio communication with the ground,
continual weather information, and precision navigation and flight
instruments changed all that and brought safety to air transport.
With domestic airline routes covering America from coast to coast and
from border to border, and with the wings of Pan American’s _Clippers_
casting their shadows over 75,000 miles of the earth’s surface, the Japs
struck at Pearl Harbor.
[Illustration: DOUGLAS DC-4]
[Illustration] AIR POWER FOR WORLD WAR II
In September, 1939, when the first Nazi Stukas screamed down on Poland,
we produced only 117 military aircraft. Our Army Air Corps could muster
only some 21,000 officers and men, and the Navy could not boast of even
that many. Neither the Army nor Navy had more than a thousand planes
each. That meant all types: trainers, transport planes, and fighters.
The Nazi _Luftwaffe_ at that time was composed of more than a million
men and 15,000 warplanes, and the Japanese had many more planes than we
ever had thought they could build. This was the beginning not only of
World War II, but of _Air War I_.
This was not the first time that the United States got off to a late
start. The same thing was true in World War I. Nevertheless, with
typical American confidence, we thought we could do it again.
Consequently, in 1940, we set as our goal the building of 50,000
warplanes.
We lost the first rounds of the fight while we were getting started. In
the South Pacific it was ten Jap planes to our one; at Wake Island, four
obsolete Marine Corps fighters flew gallantly to meet a hundred of the
foe. At Pearl Harbor hangars full of planes were caught on the ground.
At Corregidor there was a cry of “No planes!”
But a typical American once said, “We have not yet begun to fight.” As
in World War I, our military and industrial aviation leaders “rolled up
their sleeves” and began to fight. As a result, in less than three
years, they produced the greatest aërial fighting force that the world
ever has known.
Let us go back to 1920 and review the progress of our Army and Naval
aviation up to the start of World War II. We shall find out why we were
able to create unbeatable air power when the crisis came.
[Illustration] NAVAL AVIATION 1922-1935
From its earliest beginnings United States naval aviation made progress
far out of proportion to the small amount of money appropriated by the
Government. But it was a young and eager organization with a constant
desire to do things--to stretch its wings. An aërial world remained
unexplored and naval aviators were an inquisitive lot.
The first carrier, the _Langley_, with a complement of six airplanes,
became the training ground for the young naval aviators who were to lay
the foundation for the world’s greatest seagoing aërial task force.
While the _Langley_ was primitive by today’s standards, experiments with
it pointed the way for the development of improved types of
carrier-based fighting planes. However, the enthusiasm of the young
naval aviators was not shared entirely by other Navy men based on
surface craft. To them airplanes were just something to be fished out of
the sea when an engine failed. It was some time before the aviators were
able to convince these others of the exceptional value of planes in
spotting gunfire and scouting for an enemy.
Regardless of the fact that they were the Navy’s orphans, the young
pioneers kept at it. They flew the crude machines available and
developed tactics for carrier-based airplanes. They improved the
arresting gear and solved many technical problems in ways that enabled
aircraft builders to design airplanes especially suitable for use on
carriers. At the same time, it was natural that flying boats should
appeal to Navy men. The flight of the NC flying boats inspired the
development of long-range patrol boats. Naval aviators also went ahead
with experiments which were to lead to the creation of flying boats with
a range of 2,000 miles and more.