While researching sources, reading books and watching documentaries about the German invasion of Norway on April 9, 1940 and the defeat of the tiny Norwegian air force, one particular fact repeatedly comes up: modern fighter planes were ordered but not yet delivered. This fact, of course, mostly serves as an indicator towards the treatment the Norwegian military got by their government in the 1930's; too little too late.
However, no sources hardly ever mentions what kind of aircraft they were, how many or whether they would have made any difference had they been available a year earlier.
As it were, in the early morning of April 9, Norway's fighter defenses consisted of seven serviceable but outdated Gloster Gladiators; three MK Is and four MK IIs. In the course of the very uneven fight, six German aircraft were claimed for the loss of all Gladiators.
The almost mythical aircraft slated to replace the Norwegian Gladiator was the US built Curtiss-Wright Corporation ("Curtiss") P-36.
Curtiss Model 75
In May 1935 the United States Army Air Corps held a pursuit aircraft competition into which the Curtiss Aeroplane & Motor Company, Ltd. entered their Model 75. It was designed by Donovan A. Berlin, a former Northrop designer.
Being the contemporary of such designs as the Supermarine Spitfire, the Hawker Hurricane and the Messerschmitt Bf 109, the P-36 was regarded as the hottest aircraft in the US military in the mid-thirties. It was however 30-40mph slower than their soon-to-be competitors, and accounts from France before the 1940 armistice clearly indicates that the P-36 was inferior to the Messerschmitt Bf 109.
The Model 75 was an all-metal low-wing monoplane with retracting undercarriage and tail wheel, a novelty for its day. Armament consisted of a single .30 in and a single 0.50 in machine gun in the cowling above the engine, synchronized to fire through the propeller.
Its first flight was in May 1935, and on the 27th that month Curtiss submitted the plane to the pursuit aircraft competition at Wright Field in Dayton, Ohio. The competition proved a problematic one, not just for Curtiss. In fact, only Curtiss' entry was ready for the competition. Seversky Aero Corporation's entry, the SEV2-XP, was claimed to have been damaged during the transportation to Wright Field, and because of this the competition was delayed until August 15th. In the meantime, Northrop's entry - the Northrop 2A - had taken off on its maiden flight on the last day of July and disappeared over the Pacific.
Curtiss protested, claiming the delay had given Seversky an unfair advantage, convincing the US Army to push back the decision until another competition had been held in April 1936. Northrop evidently had only one prototype and did not enter the competition again.
The delay allowed Curtiss to try out a series of replacement engines since early flight tests on the Model 75 had revealed unsatisfactory performance. In spite of the attempts to improve performance by trying out four different engines, the Model 75 could not reach the 294 mph promised by Curtiss. Even though Seversky's entry also fell short with regard to performance and on top of that was more expensive, Curtiss lost the competition. The US Army Air Corps ordered 77 SEV2-XPs under the official designation P-35. The P-35 was to become the basis for the legendary P-47 Thunderbolt, but that story belongs in a different writeup.
Curtiss' Model 75 never became US Army property.
The Army does something unusual
In June 1936, Curtiss got a consolation order for three Model 75B aircraft under the designation Y1P-36. Why did the US Army do that? It has been speculated that they were getting nervous about Seversky's ability to meet delivery schedules and wanted to avoid putting all their eggs in the same basket. The Y1P-36 was to have the same engine as the P-35 - a 900 hp Pratt & Whitney R-1830 Twin Wasp - and the same armament as the Model 75.
Consolation or not, Curtiss' design had finally been accepted by the US Army.
The first Y1P-36 prototype was delivered to Wright Field in March 1937 and tested in June the same year. Army test pilots spoke highly of it after initial testing, especially its maneuverability. Despite a few ticks in the cons column, the Army ordered 210 P-36As in July 1937. This was the largest aircraft order by the US military since World War I. In April 1938, the first production P-36A was delivered to Wright Field.
Once the P-36A entered service with active squadrons, problems with the fuselage and all-metal skin set in. As a result of this the number of serviceable aircraft was constantly too low, and one particular squadron didn't receive any P-36As at all. To fill the gaps on the flight line, Seversky P-35s were used instead, probably much to the embarrassment of the Curtiss management.
In early 1941, the P-36 was regarded as obsolete and started to disappear from front-line duty. For a while it soldiered on as advanced trainers, but disappeared from that role as well. Compare this less than four year career to the near 30 year service of the F-16 Fighting Falcon!
The practice of naming aircraft other than with number designations hadn't become practice in the United States at that time, so the P-36 never got an official nickname from the US Army. Many historical sources use the export designation "Hawk" on it however.
The P-36 saw combat with many air forces in several theaters during World War II, but the only claim to fame in US service was on December 7, 1941. On that day, four P-36s of 46th Squadron managed to get airborne to intercept a second wave formation of nine Nakajima bombers. Two Japanese bombers were shot down, but it is unclear whether the P-36s or any of the P-40 Warhawks that took off together with them got the Nakajimas.
Norway and the P-36
In the autumn of 1939, Norway ordered 12 of Curtiss' P-36 export variant Hawk 75A-6. This variant had a slightly different Pratt & Whitney R-1830 Twin Wasp engine as well as a four gun armament. Later the Norwegian authorities ordered twelve more for a total of 24 75A-6 aircraft.
In February 1940, less than two months before the Kriegsmarine swarmed up the Norwegian fjords, the first of the Hawks arrived crated in Oslo harbour. By April 9, 1940, 19 of the 24 aircraft had been delivered, but only seven of those were actually assembled at Norwegian Army Materiel Command's Kjeller Airfield. Only a few of the assembled aircraft had guns fitted, and none of them had had their guns calibrated. To top it off, the air strip at Kjeller was still covered with snow, rendering the aircraft unusable without skis.
The last twelve of the 19 delivered aircraft were still in the customs building in Oslo harbour. An unknown customs officer took it upon himself to render the aircraft inoperable by smashing the instrument panels with a hammer and cutting every wire he could find, all the while German troops seized one official building after another. A display of quick thinking desperately lacking on that chaotic April day in 1940. The final five aircraft of the original order was underway to Norway and directed to England instead, later being handed over to France. The seven completed Norwegian Hawks were captured by the Germans and used by Finland in the war against the Soviet Union. They remained in Finnish service until 1948.
Only weeks before the German invasion, Norway had ordered a further 36 of the Hawk 75A-8 variant with a 1200 hp Wright R-1820 Cyclone engine. Before deliveries could start, the US government repossessed the 36 aircraft, diverting them to Little Norway in Toronto, Canada. Up until 1943 the Hawk 75A-8s were used as advanced trainers for Norwegian fighter pilots alongside the PT-19 Cornell and the AT-6 Harvard.
So, would the P-36 have made any difference during the German attack on Norway? Most probably not. Even if all of the 60 P-36s had been serviceable in the morning of April 9, 1940, they would have been outnumbered, outperformed and most important of all, flown by less experienced pilots than the Luftwaffe could muster. Luftwaffe would certainly have paid dearly in order to help occupy Norway, but it would ultimately have been a fruitless fight for the small fighter unit at Fornebu.
The P-36 today
Only 1,424 P-36s were built in various variants, making it an extremely rare aircraft. The Wright Patterson Air Force Base Museum in Dayton, Ohio has a single P-36A on display.
The P-36 around the world
The P-36 saw both peacetime and wartime use in several different countries around the globe. In fact, it was one of the very few aircraft types that fought for both sides during World War II. In no particular order, the countries were France, England, China, Iran, Norway, Holland, Finland, Peru, South Africa, Portugal and Persia.
Update: In the summer of 2003, the remains of a Curtiss P-36 H75-A6 build no. 74-47-402 was advertised for sale in St. Petersburg, Russia by one Sergei Stepanenko. This is supposedly one of the Norwegian P-36s sold to Finland by the Nazis after being looted. Some restoration has been done on it since it looks to have been salvaged from its crash site.
- Bill Gunston. American Warplanes. Salamander Books, 1986. ISBN 0 86101 227 5
- Curtiss P-36A, http://home.att.net/~jbaugher1/p36.html
- The Curtiss-Wright Corporation, http://www.centennialofflight.gov/essay/Aerospace/Curtiss_wright/Aero9.htm