Evening star. [volume] (Washington, D.C.) 1854-1972, 1929-11-10
NEW CURT|SS HAWK
READY FOR TRIALS
Improved Model of Army
Standard Plane Is
Completed.

An immensely improved version OF
the standard Army CurtiSS Hawk pur-
suit plane. which forms the backbone
of the Army Air Corps today, has been
completed for trials. 1t win bear the
designation "P-6," denoting that 1t Is
the sixth of a series of famous pursuit
planes used by the Army fghting
The P-6 is a development Of the
Hawk pursuit planes previously used
by the Army, but, with the exception
OF the tapered Hawk biplane wings,
which are practically the same, 1t has
entirely new characteristics. Greatly
improved speed and performance are
obtained through the use of Curtiss
Conqueror 60o-horsepower motor, de-
veloped from the old D-12 power plant.
Not only Is the motor much more
powerful, but extensive reduction In
weight and head resistance have been
obtained by the use OF the new pres
tone chemical liquid cooling de-
the Army Air Corps at Wright Field,
Dayton, Ohio.
Equipped for Liquid.
All Conqueror engines will be equip
ped to use prestone, which brings the
weight of liquid engines down to
that Of air-cooled power plants with
out sacrificing the advantages OF liquid
cooling. Because of the smaller amount
Of liquid required for cooling, the com
bined weight Of liquid and radiator
carried by the P-6 Hawk is l25 pounds
less than that carried by earlier Hawks.
The frontal area Of the plane, due to
the smaller radiator surfaces, Is reduced
by 40 per cent.
The new P-6 Hawk has top speed
Of 181 miles an hour, almost 25 miles an
hour faster than its predecessors, and
a cruising speed of las miles an hour.
It's stalling speed Is 61.3 miles an hour
and It's rate Of climb is said to be ALTO
| feet q minute. It can climb from sea
| level to 14400 feet in 10 minutes and
has an absolute ceiling Of 24,400 feet.
The fuselage represents radical adj
vance over the former Hawk. Chrome
| molybdenurn steel has been substituted
| for carbon steel in the framework, ef-
fecttne a considerable reduction In
| weight. The fuselage has been fully
| faired and streamlined to increase speed
and efficiency, the lines resembling
J closely those Of the fastest racing planes.
Cockpit Is ROOmier.
The cockpit has been made roomier
| and the gasoline tank has been moved
| to provide more leg room for the pilot
A new oleo landing gear also has been
4
The Conqueror engine is Of the W
type, 12-cylinder, and develops 500
horsepower at 2,400 revolutions min
| ute. It has q normal compression ratio
| and therefore Is able to use domestic
! aviation gasoline, burning BIO pounds
| of fuel and nine pounds OF lubricatlng
| oil an hour on full throttle.
The main gasoline tank holds so gal
Ions and the oil tank four gallons, Civ
! ing q cruising range at full throttle OF
| 176 miles. At cruising speed the range
| is increased to 272 miles. Auxiliary
tanks may be provided to carry so adj
ditional gallons Of fuel.
Weight Distribution.
The Pc has weight, empty, Of
| 2,430 pounds and its gross weight
loaded, Is 3,154 pounds. The useful
| pilot, 400 pounds; fuel and oil, $50
pounds, based on so gallons of gaso-
line: equipment, 81 pounds, and arnaa-
ment, 1877 pounds To
/ The overall length Of the plane Is
] % feet inch: 1t is 8 feet 8 inches
| high and has wing span of 81 feet 6
inches. The wing loading is only 1852
pounds o square foot, and the power
loading 5.25 pounds for each horse
The wings, of Clark ''Y" aerofoil Sec
ton, tapered, are deeply staggered, as
In the old Hawk, the leading edge of
the upper wing being nearly 20 inches
ahead Of the leading edge OF the lower
wing.
The propeller is of Air Corps design,
with diameter OF feet 8 inches and
q pitch OF approximately 14.S degrees.