Evening star. [volume] (Washington, D.C.) 1854-1972, 1929-01-06
WIND TUNNEL AIDS
AIR SPEED TESTING
Langley Field Shaft Offers
Chance to Study Velocity
of 1000 Miles an Hour.

Looking forward to the days when
AirplaneS will be riding through the air at
the rate of 900 miles an hour, speed
approximately the same as that with
which sound travels. or air leaves the
vicinity of violent explosion, the Ma
tional Advisory Committee for Aero
nautics has Just set up in its research
laboratories. at Langley Field, Va,
wind tunnel, or air shaft for the study
of such hitherto unknown air velocitieS
on model airplanes built to scale and
strength of one-twenty- thousandth.
Phenomena are believed by the re-
search engineers at Langley Field to
exist at or about the speed OF sound,
concerning which science Is wholly
ignorant. Facilities for the study OF
such a tremendous wind velocity never
before have been developed, and 1t Is
believed that the findings to be mace
with the Langley Field shaft will be
of inestimable value to the develop
ment of high-speed airplanes, in addi-
ton to the value to be derived from
the shaft through the testing Of ma
tepial strength.
The air shaft was installed at the
instance of Rear Admiral David w
TAYLOR, retired a member OF the Ma
tional Advisory Committee for Aero
nautics. who has taken considerable IN
terest in the few experiments already
made with it, In the shaft. 1t has oeen
found. can be studied scale MODELS 0!
the various types of aircraft now uSeo
bv the Government and by private in
terests and models OF planes now III
The course of development.
Whipped Through Tunnel.
The shaft is about foot in diameter,
and built in much the same way as the
larger wind tunnels in use at the N. A.
e 4 laboratories It is hooked up with
the h-compression wind tunnel useo
nv the N A. C. A. engineers in such
wav that the circulating air OF the COM
preston tunnel picks up the air OF the
hugh room in which 1t is installed anu
whips it through the high-veloclty tun-
mel by suction. In 1t can be measured
wing stresses and lifts for the time
rwhen and If. a motor can be built to
carry a plane through the air at sucIl
a rate as to encounter SUCH Wlno
velocity. .4;,,
Another new development in AVIATION
at,Idv is the refrigerated wind tunnel IN
which a study IS being made or ice
formation on the wings and working
narts of planes From the experiments
already made it has been touno thaV
parafin. which was used on the trans-
atlantic plane Bremen in It's east-WeSt
faioht across the ocean, affords nttie
,,rotection to the plane. The fact that
ice did not form on the Bremen was
due N. A. c. A. engineers point OUT
ia the fact that it did not run INTO
ANYTHING likely to bring ABOUT Ice
formations.
May Not Keep in Air.
No cure for the ice formation, which
Is one of the greatest hazards IN Trains
oceanic faying, has been found as YET
hut A great deal has been learned apouV
II bv the use of the refrigerated tuIlLei.
One thing that has been OF great Value
tn aviation, the N A. G. A. engineers
so;S is the discovery that ice formation
On nlanes is not of the sort that would
v-eight, II down. Little extra weight Is
added by ice, but the formation OF the
ice comes in icicles and sheets OF ice
which. pointing upward ana ooWn"aIo
instead of forming uniform coat OH
the wings and struts Of the plane, con,
stitute q drag likely to pun the speed
of a heavily laden plane down TO sucn
an extent that the plane would not DC
able to keep in the air.
THE results of these experiments are
constantly being given to the alrplane
industry, the Army, Navy and Marine
Germs and other aviation interests oy
the Government and none OF the oe-
vices developed by the N. A. c. A. Is
Much of the energy of the staff at
the N. A. C. A. laboratory is being OIL
rected toward the perfection OF an air.
plane Diesel engine. This engine, as
| PARTIALLY developed, Is one which WORKS
an crude oil without ignition or car
bIretion.
Improvement Needed.
Some success already has been found
with the engine but considerable I'M
movement is necessary before the en-
zine now being experimental upon can De
turned over to the airplane industry Tor
production and actual use in planes. In
fhis engine. crude oil is Snot INTO the
engine cylinders at high pressures,
sometimes at pressures as high as o,ooO
pounds square inch. me OH spray 40
then compressed with air, and the neat
thus generated ignites the oil. giving
the motor its power. The engine has
been made to turn up 1000 revolutions
a minute. Considerable study Is nee
essary, however, before the engine VIII
be a finished product.
For the Study of the oil jets for this
new motor there has Deen devised
motion picture taking apparatus, cap
able of photographing the spray at the
rate of 5000 pictures second. The pic
lures are taken by means of an electric
spark synchronized to the camera and
the oil spray.
For complete information on air pres
gures on airplane, wings and fuSelages
a plane has been devised with hundreds
of tiny holes in its wings and fuselage,
all the holes connected by tubes with
Q delicate Photographic instrument
mounted in the plane. which records,
photographically the varying presSures
to which a plane is subjected while in
flight. This plane is in process of con-
struction and will be put through the
test flights necessary for the data at an
early date.