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Curtiss XP-37 (Allison Hawk)

United States (1937)
Picture of Curtiss XP-37 (Allison Hawk) Fighter Prototype
Picture of Curtiss XP-37 (Allison Hawk) Fighter Prototype Picture of Curtiss XP-37 (Allison Hawk) Fighter Prototype

The Curtiss XP-37 was an attempt by the USAAC to transform the radial-powered P-36 Hawk into an inline piston-engined fighter.


Detailing the development and operational history of the Curtiss XP-37 (Allison Hawk) Fighter Prototype.  Entry last updated on 5/13/2016. Authored by Staff Writer. Content ©www.MilitaryFactory.com

The American Curtiss P-36 "Hawk" marked one of the earliest of the all-modern fighters to appear in the years leading up to World War 2 (1939-1945). It was joined by the likes of the British Hawker Hurricane and the German Messerschmitt Bf 109 but failed to find the same wartime success as its contemporaries. Completed with a Pratt & Whitney "Twin Wasp" air-cooled radial piston engine, 215 examples were built as the P.36 and a further 900 were exported under the "Hawk 75" designation. The design was eventually developed into the classic P-40 "Warhawk".

The United States Army Air Corps (USAAC) sought additional value in their P-36 to the point that they commissioned Curtiss in 1937 to develop the aircraft with the Allison V-1710 turbo-supercharged inline piston engine of 1,150 horsepower. This begat the prototype "XP-37" monoplane fighter which retained much of the original's components including its well-streamlined airframe. To compensate for the length and weight of the new engine installation at the nose (and to better balance the revised center-of-gravity), the cockpit was positioned further aft along the dorsal spine which immediately differentiated it from the earlier P-36.

In this configuration, the aircraft was flown for the first time during April 1937 and managed a maximum speed of 340 miles per hour against the P-36A's 313 mph top speed. However, the all-important turbo-supercharger proved troublesome during testing and there grew concern about the nose length and position of the wing mainplanes which considerably inhibited the pilot's forward vision. Views to the rear of the aircraft were no better as the raised fuselage spine and tail planes further masked any approaching danger from the rear.

Nevertheless, USAAC authorities were sold on the potential performance gains of this sleek entry and ordered the XP-37 in a service test form as the "YP-37" through a thirteen-strong batch order. Engineers continued to work on the turbo-supercharger but reliability remained an issue. A developmental-minded YP-37 managed a first flight during June of 1939 but the temperamental aircraft was soon passed over for a more promising - and conventional - venture, this to become the P-40 Warhawk which became an ultra-critical American fighter of the early-war years.


Picture of the Curtiss XP-37 (Allison Hawk) Fighter Prototype
Picture of the Curtiss XP-37 (Allison Hawk) Fighter Prototype



Any available statistics for the Curtiss XP-37 (Allison Hawk) Fighter Prototype are showcased in the areas immediately below. Categories include basic specifications covering country-of-origin, operational status, manufacture(s) and total quantitative production. Other qualities showcased are related to structural values (namely dimensions), installed power and standard day performance figures, installed or proposed armament and mission equipment (if any), global users (from A-to-Z) and series model variants (if any).






Our Data Modules allow for quick visual reference when comparing a single entry against contemporary designs. Areas covered include general ratings, speed assessments, and relative ranges based on distances between major cities.

Image of collection of graph types

Relative Maximum Speed Rating
Hi: 400mph
Lo: 200mph
    This entry's maximum listed speed (342mph).

    Graph average of 300 miles-per-hour.
City-to-City Ranges
NYC
 
  LON
LON
 
  PAR
PAR
 
  BER
BER
 
  MOS
MOS
 
  TOK
TOK
 
  SYD
SYD
 
  LAX
LAX
 
  NYC
Graph showcases the Curtiss YP-37's operational range (on internal fuel) when compared to distances between major cities.
Aviation Era
Pie graph section
Pie graph section
Pie graph section
Pie graph section
Pie graph section
Useful in showcasing the era cross-over of particular aircraft/aerospace designs.
Unit Production Comparison
Comm. Market HI*: 44,000 units
Military Market HI**: 36,183 units
14
14


  * Commercial Market High belongs to Cessna 172.

  ** Military Market High belongs to Ilyushin Il-2.


Altitude Visualization
Small airplane graphic
  Compare this entry against other aircraft using our Comparison Tool  
National Flag Graphic
Origin: United States
Year: 1937
Type: Fighter Prototype
Manufacturer(s): Curtiss-Wright - USA
Production: 14
Global Operators:
United States (cancelled)
Historical Commitments / Honors:

Military lapel ribbon for Operation Allied Force
Military lapel ribbon for the Arab-Israeli War
Military lapel ribbon for the Battle of Britain
Military lapel ribbon for the Battle of Midway
Military lapel ribbon for the Berlin Airlift
Military lapel ribbon for the Chaco War
Military lapel ribbon for the Cold War
Military lapel ribbon for the Cuban Missile Crisis
Military lapel ribbon for the Falklands War
Military lapel ribbon for the French-Indochina War
Military lapel ribbon for the Golden Age of Flight
Military lapel ribbon for the 1991 Gulf War
Military lapel ribbon for the Indo-Pak Wars
Military lapel ribbon for the Iran-Iraq War
Military lapel ribbon for the Korean War
Military lapel ribbon for the 1982 Lebanon War
Military lapel ribbon for the Malayan Emergency
Military lapel ribbon for the attack on Pearl Harbor
Military lapel ribbon for the Six Day War
Military lapel ribbon for the Soviet-Afghan War
Military lapel ribbon for the Spanish Civil War
Military lapel ribbon for the Suez Crisis
Military lapel ribbon for the Vietnam War
Military lapel ribbon for Warsaw Pact of the Cold War-era
Military lapel ribbon for the WASP (WW2)
Military lapel ribbon for the World War 1
Military lapel ribbon for the World War 2
Military lapel ribbon for the Yom Kippur
* Ribbons not necessarily indicative of actual historical campaign ribbons. Ribbons are clickable to their respective campaigns/operations.
Measurements and Weights icon
Structural - Crew, Dimensions, and Weights:
Unless otherwise noted the presented statistics below pertain to the Curtiss YP-37 model. Common measurements, and their respective conversions, are shown when possible.

Operational
CREW


Personnel
1


Dimension
LENGTH


Feet
28.54 ft


Meters
8.7 m


Dimension
WIDTH


Feet
37.73 ft


Meters
11.5 m


Dimension
HEIGHT


Feet
8.20 ft


Meters
2.5 m


Weight
EMPTY


Pounds
4,575 lb


Kilograms
2,075 kg


Weight
LOADED


Pounds
6,030 lb


Kilograms
2,735 kg

Engine icon
Installed Power - Standard Day Performance:
1 x Allison V-1710 inline piston engine developing 1,150 horsepower and driving a three-bladed propeller in the nose.

Performance
SPEED


Miles-per-Hour
342 mph


Kilometers-per-Hour
550 kph


Knots
297 kts


Performance
RANGE


Miles
621 mi


Kilometers
1,000 km


Nautical Miles
540 nm


Performance
CEILING


Feet
32,808 ft


Meters
10,000 m


Miles
6.21 mi


Performance
CLIMB RATE


Feet-per-Minute
3,400 ft/min


Meters-per-Minute
1,036 m/min

Armament - Hardpoints (0):

None Fitted.
Variants: Series Model Variants
• XP-37 - Prototype designation
• YP-37 - Service Test aircraft; batch of thirteen ordered.
• P-37 - Assumed in-service designation