Evening star. [volume] (Washington, D.C.) 1854-1972, 1936-01-26
SOME MEN ARE LOST
Government Now Requires Trials to Be Made
by Manufacturers When Machines
Are Submitted.

itary load, either actual or IN the form
Of ballast. and the necessary test
equipment are installed. A pilot from
the test section then takes the ship
up for q 30-minute flight. to become
acquainted with the way the plane and
engine perform. .
The next step Is the celebration Of
the air speed meter-perhaps the most
dangerous job to be habitually per-
formed by Air Corps test pilots. There
Is 2-mile speed course laid out
on level ground q short distance from
Wright Field, with Q highway at one
end and a rather steep hill only
three quarters Of q mile from the
other.
The pilot must come in at top
speed, without preliminary dive;
level of at one end Of the course
only S or 10 feet above the ground,
start his stop-watch the instant he
passes the pylons and fly absolutely
level and at constant speed the full
length Of the course, note the reading
Of the air speed meter and stop the
watch at the other end Of the course.
He then pulls up bit, jots down the
readings of the meter and watch. and
comes in again at the same indi-
Gated speed from the other end Of
the course, so that he will have a
record of the time required to fly the
course both with and against the
wind, II any.
These flights are made on quiet
days. The next time he repeats the
process 10 miles ali hour slower, as
shown by his air speed meter, and
this Is kept up at 10-mile-an-hour
intervals until the last course Is flown
at Just above stalling speed.
dying thus close to the ground Is
always ticklish work. It Is doubly
so when the pilot must read instru-
ments, as well as watch the ground
and concentrate on keeping the plane
absolutely level. A Paragraph records
the slightest variation In altitude,
and all those courses not flown level
are thrown out and must be repeated.
If the engine should take a notion
to quit while over the course. the
plane could be landed safely, but If it
should stop at the end of the course
when flying at the lower speeds the
plane would pillow into the hill. Capt.
STREET. had his engine cut out on
him near the end Of the course while
flying at ITO miles an hour. At this
speed he was able to pull up, turn
and make landing.
Recently another method Of cali
bration has been tried for lombard
ment and heavily loaded planes. One
plane is taken up, the air speed Of
which Is known to be accurate. An
other pilot will fly the plane being
tested, the wing tips Of the two ships
almost touching. The first pilot will
watch his air speed meter, and when
it registers, say 230 miles an hour,
he will nod The other pilot will
then RECORD the reading of his own
meter. They then slow down by 10
mile periods and repeat the process
until q full set Of celebrations has
been obtained.
The next Job of the test pilots Is to
determine the power output Of the
engine while flying at its rated alti-
tude. Then they "fly the sawtooth"
to determine at what altitude, as in
dicated by the air speed meter. the
plane will climb the fastest.
This test is known as the sawtooth
because the Paragraph record resem-
bles the business edge Of q saw. The
test is made by climbing from 1000
to 5000 feet for instance, with the air
speed at 1876 miles an hour. The plane
is then brought back to 1000 feet and
with the same throttle setting the
stick is pulled back until the climb is