Nederlandse Modelbouw en Luchtvaartsite

Dutch Modelling and Aviation

In Memoriam

Klaas Willem Jonker
† April 30, 2018

On Monday 30 April 2018, Wilko Jonker died after a long illness at the age of 58. He leaves behind a wife and two children. The Dutch military aviation and plastic modeling were his hobby and on this website he shared all the knowledge he has collected over the years. His hobby has been able to distract him from the persistent disease in his body until the last week of his life. The contacts with other hobbyists were a major support for him.

This website will be maintained by different people for as long as possible, so that other enthusiasts can continue to benefit from extensive content.

Curtiss Hawk 75A-7


The Curtiss Hawk 75 was developed in 1933/1934 as a private initiative of the Curtiss factory. The all-metal aircraft had a Wright XR 1670-5 radial engine of 900 horsepower.

The prototype was equipped with a .30 inch and .50 inch machine gun, at that time the standard armament of the USAAC.

The prototype made ​​its first flight on May 6, 1935.

Later that month there was a USAAC competition for the delivery of a new fighter.

However, the P-35 Seversky competitor crashed on the flight to Wright Air Force Base, Ohio, and had to be rebuilt.

Curtiss had therefore time to improve the aircraft and exchanged the engine for a Wright XR 1820-30 of 910 horsepower and gave the renewed machine the designation Curtiss 75D, while the first prototype was designated as Curtiss 75B.

Unfortunately Seversky won the competition. However, because of the increasing tensions, especially in Europe, Curtiss received in June 1936 a contract to supply three test aircraft, designated Y1P-36 fitted with a Pratt & Whitney R1830-13 Twin Wasp rated 900 hp .

These performed very well, so in 1937 an order for 210 examples, designated as P-36A followed. Because of a variety of childhood diseases such as blistering of the aircraft skin at the wheel well, problems with the exhaust and weaknesses in the airframe, the aircraft was not used much operational, so it was considered  to be outdated when the problems were solved and became the type was transferred to training units.

France was already interested in the type before the P-36A entered in production. But because the Curtiss 75 costs almost twice as much as the French Bloch MB150 and Morane MS406, after a period and mainly because of the political tensions a first order for 100 Curtiss 75 A-1 or H75-SC1 with Pratt & Whitney R-SC -1830-G and French equipment. France received over 300 aircraft.


Curtiss 75A:
demonstration aircraft, which was equipped with different engines.
  • Curtiss-75A-1: 100 examples for France with R-1830 SC-G 900 hp and four 7.5 mm machine guns.
  • Curtiss 75A-2: 100 examples for France with R-1830 SC-G or R-1830 SC3-G 1050 hp and six 7.5 mm machine guns.
  • Curtiss 75A-3: Third series for France; Built 135 aircraft; 133 delivered.
  • Curtiss 75A-4: Last series for France and 75A-2 with Wright R-1820-G205A Cyclone 1,200 hp; Built 200 examples; 81 aircraft were delivered; rest taken over by the RAF as Mohawk IV.
  • Curtiss 75A-5: License Building in China, later to India. Later entered service as Mohawk IV with the RAF.
  • Curtiss 75A-6: version for Norway. After invasion sold to Finland.
  • Curtiss 75A-7: Version for the Dutch East Indies with Wright R-1820 Cyclone 1200 hp; one .50 inch and one .303 inch machine gun in the nose and two .303 inch machine guns in the wings; later changed to two .303 inch machine guns in the nose; bomb load of 2 x 50 lbs (23 kg)
  • Curtiss 75A-8: version for Norway used for training in Canada; Later to Peru.
  • Curtiss 75A-9: 10 examples for Persia. Taken over by the RAF as Mohawk IV.
Curtiss 75B:
first prototype with Wright R-1820 engine.
Curtiss 75D:
Prototype with Wright R-1670 engine.
Curtiss 75E:
Three aircraft for testing by the USAAC with USAAC designation Y1P-36
Curtiss 75H:
simplified version with fixed landing gear, supplied to China and Argentina.
Curtiss 75i:
factory designation of Curtiss YP-37, equipped with an Allison V-1710 of 1150 horsepower.
Curtiss 75J:
Curtiss 75A equipped with turbo-supercharger.
Curtiss 75K:
a non-built version with a Pratt & Whitney R-2180 Twin Hornet.
Curtiss 75L:
Factory Name of the P-36A
  • Curtiss P-36A: Production version for USAAC
  • Curtiss P-36B: P-36A temporarily fitted with an R 1830-20 of 1,100 horsepower.
  • Curtiss P-36C: last 30 examples of USAAC series P-36As with R 1830-17 of 1,200 horsepower and a .303 machine gun in each wing.
  • Curtiss XP-36D: A P-36A with two .50 inch machine gun in the nose and four .303 inch machine guns in the wings.
  • Curtiss XP-36E: Standard P-36A with four .303 inch machine guns in the wings.
  • Curtiss XP-36F: P-36A experimental equipped with two 23 mm Madsen cannons.
  • Curtiss P-36G: designation of Curtiss 75A-8
Curtiss 75M:
simplified version with fixed landing gear and Wright R-1820 for China, built by Curtiss and in China.
Curtiss 75O:
Simplified version with fixed undercarriage; 30 examples built for Argentina and another 20 aircraft built under license by Fabrica Militar de Aviones.
Curtiss 75P:
Production 36A (38-010) with Allison V-1710 inline engine; prototype for the Curtiss P-40.
Curtiss 75Q:
Two demonstration aircraft for China.
Curtiss 75R:
75A Curtiss R-1830 SG2-R turbo supercharger.
Curtiss 75S:
Factory Display for XP-42 test device for research of cooling of liquid-cooled inline engines.


Technical information
Length: 8,7 m Wingspan: 11,28 m
Height: 2,82 m Wing area: 21,9 m2
Empty weight: 2121 kg Max. start weight: 2661 kg
Max. speed: 518 km/hr Rate of climb: 762 m/min
Range: 1046 km Service ceiling: 9860 m;
Engine type: One Wright Cyclone GR-1820-G205A rated 1200 Hp.
Armament: Four 7.7 mm machine guns: two wing mounted, two nose mounted.
Two bombs of 50 kg each