Boeing XP-9

Infobox Aircraft
name=Boeing XP-9
type=Monoplane fighter
manufacturer=Boeing


caption=
Boeing XP-9

designer=
first flight=18 November 1930
introduced=
retired=
number built= 1
status= Cancelled
primary user=United States Army (intended)
more users=
unit cost=
developed from=
variants with their own articles=

The Boeing XP-9 (company Model 96) was the first monoplane fighter aircraft produced by the United States aircraft manufacturing company Boeing. It incorporated sophisticated structural refinements that were influential in later Boeing designs. The sole prototype exhibited unsatisfactory characteristics with its lack of pilot visibility directly leading to its cancellation. [Yenne, Bill. "World's Worst Aircraft". Greenwich, CT: Dorset Press, 1990. ISBN 0-88029-490-6]

Design and development

The XP-9 was designed in 1928 to meet the requirements of a US Army request for a monoplane fighter. Its primary contribution to aircraft design was its semi-monocoque construction, which would become a standard for future aircraft. Boeing employed the structural features of the XP-9 into their contemporary P-12 biplane fighter when the P-12E variant incorporated a semi-monocoque metal fuselage structure similar to that of the XP-9. The undercarriage arrangement of the P-12C had also been first tried out on the XP-9 and then transferred into the production model."Pedigree of Champions: Boeing Since 1916" 1969]

Operational history

The prototype XP-9, marked "A 028-386", was first flown on 18 November 1930. It had impressive stats on the specification sheet, but it quickly became apparent that its large (6 ft chord) wing, which was placed atop the fuselage directly in front of the pilot, obstructed downward visibility so badly that simple landing maneuvers were hazardous."Pedigree of Champions: Boeing Since 1916" 1969] Test pilots at the Army Test Centre at Wright Field found that the XP-9's inherent instability was so severe that immediate modifications were requested to increase the size of the vertical tail. [Baugher, Joe. "Boeing XP-9". 6 June 1998. [http://home.att.net/~jbaugher1/p9.html] Access date: 17 March 2007. ] An enlarged vertical tail surface with smooth metal skinning was introduced, but failed to effect any significant improvement, and this revised XP-15 was grounded for instructional airframe use in August 1931, after only 15 hours of test flying.Eden and Moeng 2002, p. 74-77.]

Variants

;Model 96, XP-9: one built;Y1P-9: option for five service test aircraft under the P-12D contract, option was not taken upEden and Moeng 2002, p. 74-77.] ;XP-15: redesignated XP-9 after modification of vertical tailEden and Moeng 2002, p. 74-77.]

Operators (planned)

;flag|United States|1912
*United States Army

Specifications (Boeing XP-9)

aircraft specifications
ref="The Complete Encyclopedia of World Aircraft" [Eden and Moeng 2002, p. 321.]
plane or copter?=plane
jet or prop?=prop
crew=1
capacity=
length main= 25 ft 1.75 in
length alt= 7.66 m
span main= 36 ft 6 in
span alt= 11.13 m
height main= 7 ft 10.25 in
height alt= 3 m
area main= 210 ft²
area alt= 19.51 m²
airfoil=
empty weight main= 2,669 lb
empty weight alt= 1,211 kg
loaded weight main=
loaded weight alt=
useful load main=
useful load alt=
max takeoff weight main= 3,623 lb
max takeoff weight alt= 1,643 kg
more general=
engine (jet)=
type of jet=
number of jets=
thrust main=
thrust alt=
thrust original=
afterburning thrust main=
afterburning thrust alt=
engine (prop)= 1
type of prop=Curtiss SV-1570-15 Conqueror
number of props=
power main= 600 hp
power alt= 448 kW
power original=
max speed main= 185 knots
max speed alt= 213 mph, 343 km/h
cruise speed main= 156.4 knots
cruise speed alt= 180 mph, 290 km/h
never exceed speed main=
never exceed speed alt=
stall speed main=
stall speed alt=
range main= 369 nautical miles
range alt= 425 mi, 684 km
ceiling main= 26,800 ft
ceiling alt= 8,170 m
climb rate main= 1,560 ft/min
climb rate alt= 7.9 m/s
loading main=
loading alt=
thrust/weight=
power/mass main=
power/mass alt=
more performance=
armament=2 machineguns, one .30 (7.62mm) and one .50 (12.7mm), 125 lbs bombs.
avionics=

References

Notes

Bibliography

* Eden, Paul and Moeng, Soph. "The Complete Encyclopedia of World Aircraft". London: Amber Books Ltd., 2002. ISBN 0-7607-3432-1.
* "Pedigree of Champions: Boeing Since 1916, Third Edition" (booklet). Seattle, WA: The Boeing Company, 1969.

External links

* [http://www.wpafb.af.mil/museum/research/p9.htm United States Air Force Museum: Boeing XP-9]

aircontent
related=
similar aircraft=
lists=
* List of military aircraft of the United States
* List of fighter aircraft