Evening star., 1939-01-29

haustive tests, both aloft and on the
surface. On November she was
turned over to engineers of the Civil
Aeronautics Authority to go through
the whole schedule again. During the
company tests alone, over period OF
three months, Test Pilot Eddie Allen and
his engineering crew went through some
5000 miles of actual flying. some $50
miles of taxing and 80 take-offs and
landings. Twenty working hours OF
engineering study have been necessary to
analyze each hour of test flying. The
flight and recording work aloft kept
test crew of 10 men busy aboard the air
plane and nearly four times the number
on the ground.
A Record Performer.
If measurements made during the
tests had been officially recorded in ac-
cordance with international procedure,
the superclipper would have established
at least six new world records for speed
and altitude with loads. She carried
loads of up to $4,000 pounds. In terms
of weight this means that she could
have taken aboard the Sikorsky S-42
Bermuda Clipper, now in regular service
between New York and Bermuda, COM
pletely equipped, fueled and stated and
flown away with her.
The tail assembly, of the superclipper
alone is larger in area than the whole
wing of a 10-passenger twin-engined
Lockheed Electra transport airplane-
The controls, nevertheless, can be
worked with two fingers.
At first Mr.. Allen and the members
of his test crew were puzzled by an ap-
parently unexplainable landing char
acteristic of the big Boeing. They would
get down to within about IS feet of the
water and for seemingly no reason at
all, the clippers nose would start drop
ping. Finally one of the observers ashore
solved the problem by radio. The flight
officers seat is so far away from the
landing step, about rs feet, that the ship
was actually landing before they knew
it had touched water. They could
neither feel nor hear the step slicing
into the water, which brought the nose
down into landing position.
The flight deck of the Boeing is ar
ranged to reduce to minimum flight
fatigue"-an important safety factor.
Space on this deck is equivalent to the
entire cabin space of Douglas DC-3
21-passenger transport. Each fight Of
flcer has a space equal to the whole
DC-3 cockpit except the navigator, who
has twice that much room. There is a
telephone system arranged to permit
conference discussions" with phone at
every station on the flight deck and at
the engineers stations in the wing.
Repairs Possible in Flight.
From the flight deck there are passages
through the wing to each of the four
engine stations. All of the engine auxili-
aries fuel and electrical systems are ac-
cessible for adjustment, inspection and
repair during flight. Each individual
engine room is as large as a four-place
sport cabin plane. Any section of the
wing also may be reached for inspection
and repair
During the fight testing 2e1 "engi-
neer's stethoscopes" were trained on all
the big ships working parts. The read
ings were received on the flight deck at
six test headquarters, in which there
were more than 100 instruments in con-
slant operation. A single potentiometer
there was arranged to give readings at
IS different points. The intervals be-
tween readings on some Of the test dials
were so fast that motion picture cameras
were employed to record them.
Temperature readings could be made
at 81 points in and around the engines.
Altogether, there were instruments to
give temperature readings at SO points
throughout the ship and constant rec
ords of pressure at II points. Every
thing was measured, from the pressure
and temperature of the air flowing
through the cooling fms on the engine
cylinders to the pressure Of the air on
the wing tips during . turn. There was