The Curtiss P-40 Warhawk/Tomahawk/Kittyhawk was an American fighter and ground attack of the Second World War, and probably one of the most underrated combat aircraft of this conflict. Popular opinion after the war was that the P-40 was a mediocre performer, whilst the actual truth is far different.
Granted, the Warhawk was not a good fighter at high altitudes, but at medium and low altitudes it was a formidable air-to-air opponent and a rugged and deadly ground-attack aircraft.
The P-40 was thrown into the fight early and served in China with the famous Flying Tigers during the Japanese invasion of China.
The type saw service with British and Commonwealth squadrons in the Mediterranean and North Africa and was the first American fighter to fly and fight against the Japanese on the first day of the Pacific War.
The P-40 served until the cessation of hostilities and was the third-most-produced American fighter of the war.
While not being the best or fastest fighter of the war, the P-40 allowed the Allies to take on the Axis air forces on a fairly level playing ground, and hold their own until newer fighter designs became available later in the war.
Design and Development
The P-40 was a direct descendant of the Curtiss P-36 USAAC fighter, and the prototype XP-40 was actually the 10th production P-36 with an Allison in-line liquid-cooled engine instead of the radial air-cooled power plant normally fitted.
Test results were somewhat disappointing until the air inlet and radiators were moved to a new position under the nose, after this the design showed considerable promise.
Due to this prototyping process, the P-40 had a relatively short design phase, and the final airframe configuration was confirmed and approved in short order.
The prototype first flew in October 1938, and further tests and modifications followed, including a stint in the National Advisory Committee on Aeronautics (NACA) wind tunnel to test high-speed flight characteristics.
Improvement was shown to the extent that the USAAC ordered 524 examples in April 1939, as the world was slowly descending into war.
The P-40 had several major production variants, and these versions were known by different designations when flying with the Russians or the British Commonwealth air forces. Total production of all P-40 variants totalled 13,738 units constructed from 1939-1944.
The P-40 A/B/C models were the first production models and were noted for having nose-mounted browning machine guns firing through the propeller arc, utilising interrupter gear.
These versions were collectively referred to as the Tomahawk in British/Russian service, and the ‘C’ mark (Tomahawk IIB) introduced many improvements in survivability and armament, but the increased weight reduced the aircraft’s top speed.
The P-40D or Kittyhawk I was only produced in small numbers, but eliminated the nose guns and introduced a more powerful engine. The following P-40E (Kittyhawk IA) increased the number of wing guns and had a slightly more powerful engine fitted.
This variant bore the brunt of aerial fighting during 1942-43, serving in combat in the European and Pacific theatres with all Allied air forces.
The P-40 F/L (Kittyhawk II) introduced a Merlin engine, which increased performance, and allowed better high-altitude performance than her forebears. This version was used extensively by USAAF forces in the Mediterranean theatre of operations.
The P-40K (Kittyhawk III) reverted back to an improved version of the Allison power plant and was widely used by both American and Allied forces in all theatres, particularly the China-Burma-India (CBI) operational zone.
The succeeding P-40M production run was mainly diverted to Russian and British/Commonwealth as the Kittyhawk III, but some aircraft were retained in the continental US for use as training aircraft.
The final major production model of the P-40 was the ‘N’ version (Kittyhawk IV), which reduced the gun armament in an attempt to improve dogfighting performance, however by this time the Warhawk/Kittyhawk was being solely employed on ground-attack duties – which led to its nickname of ‘B-40’.
All performance figures, armament details and dimensions are given for the P-40E Warhawk (Kittyhawk 1A).
The P-40 had a height of 10 feet 8 inches (3.25 metres), a length of 31 feet 8 inches (9.660 metres) and a wingspan of 37 feet 3 inches (11.360 metres).
Empty, the weight of the P-40 registered as 5,922 pounds (2.682 kilograms), and the gross loaded mass of the aircraft was 8,515 pounds (3,862 kilograms).
The power plant was an Allison V-1710-39 single-stage supercharged V-12 liquid-cooled piston engine driving a three-blade Curtiss-Wright constant speed airscrew, and this produced 1,240 HP.
The max speed was 334 mph (538 km/h) and the type had a very high cruise speed of 308 mph (496 km/h). The range was a reasonable 716 miles (1,152 kilometres), and the P-40 had a service ceiling of 29,100 feet (8,900 metres).
This model of the P-40 was armed with six Browning M2 .50 calibre heavy machine guns, mounted in the wings. An ordnance load of up to 2,000 pounds (910 kilograms) could be carried under the fuselage and on two underwing mounting points, and the wing mounts were plumbed to allow the employment of drop tanks for extended range.
The P-40 had a distinguished combat record during the Second World War and fought in nearly all the major theatres of operations during the conflict.
Over two hundred Allied fighter pilots became aces flying the type, and when flown by expert pilots at medium and low altitudes was a formidable aerial opponent for German, Italian and Japanese fighters.
The airframe thrived in harsh environments, and maintenance was easily able to be performed at advanced airfields under austere conditions.
The lack of a double-stage supercharger meant that the P-40 was a mediocre performer at high altitudes, but was a good dogfighter at lower heights.
The aircraft was particularly noted for two things; the ability to pull very tight high-g turns at moderate to high speeds, and the ease it which it could out-dive its opponents.
The Japanese Zero could turn tighter at low speeds, but P-40 pilots were trained not to get into a low-speed turning contest with the Zero, relying on ‘boom and zoom’ combat tactics instead.
The Warhawk first saw combat with the AVG in China and enjoyed considerable success against Japanese fighters and bombers.
When Chinese air force squadrons were equipped with the Warhawk and USAAF squadrons entered the theatre after the Pearl Harbour attack, the Allies were able to gain air superiority in northern free China and maintained this until the end of the war.
The Royal Air Force did not use the P-40 in high-altitude combat, but the type was a stalwart of the Desert Air Force (DAF) where low-level performance was more desirable.
The highest-scoring ace in the Kittyhawk, Australian Clive Caldwell (22 victories) said that the P-40 was ‘almost without vice’, and many other Allied aces who flew the type praised the many good qualities of the aircraft in aerial combat.
The P-40 fought on the very first day of the Pacific War, where despite suffering many losses on the ground, a number of P-40s were able to take to the skies during the Japanese attacks on Pearl Harbour and shoot down several of the attacking aircraft from the Japanese carriers.
Along with the Grumman Wildcat, the P-40 shouldered the harsh burden of battling often superior Axis designs with consummate success, and both aircraft were responsible for breaking Japanese air superiority during those desperate early days of 1942-43.
The Warhawk also fought during the Japanese advances in the Philippines and south-east Asia, and USAAF squadrons were responsible for the security of Australian northern skies until sufficient US and British aircraft arrived to equip the RAAF fighter squadrons.
In Australian service, the Kittyhawk performed valiantly in the ground-support role during the Battle of Milne Bay, which was the first Japanese ground defeat of the Pacific War.
Australian, New Zealand, Canadian and British pilots employed the P-40 in the ground attack role in both the Pacific and Mediterranean theatres of operation.
The Russians employed the P-40 in a variety of roles on the Eastern Front, and the airframe was appreciated for the ease of maintenance requirements, and its ability to reliably function under the extreme weather conditions encountered in that region.
The Russians considered it to be a good fighter, and superior to the Hawker Hurricane with which some Soviet units were equipped.
The P-40 ended the war by flying ground-attack sorties over continental Europe as the conflict drew to a close. After the end of the fighting the P-40 was retired from most Western inventories, but continued to serve for a number of years with smaller air forces. The last P-40 in active service was retired by the Brazilian Air Force in 1958.
The P-40 series of fighters was another case of the right aircraft at the right time and did much to stave off Allied aerial defeat in the dark early years of the Second World War.
Well-designed, tough, durable and agile when properly flown, the P-40 served with distinction with many nations during the war and gained a deserved reputation as a good fighter, and formidable ground-attack aircraft.
The Warhawk was overshadowed by later and superior Allied fighter designs, and its reputation undeservedly suffered after the war, but aviation writers are far more lenient and salutary towards the P-40 these days.
Today, it is remembered as a fighter aircraft that held the line during some dark times, and as such deserves its place as one of the most iconic fighters of the Second World War.
- Crew: One
- Length: 31 ft 8.5 in (9.665 m)
- Wingspan: 37 ft 3.5 in (11.367 m)
- Height: 10 ft 8 in (3.25 m)
- Empty weight: 5,922 lb (2,686 kg)
- Gross weight: 8,515 lb (3,862 kg)
- Powerplant: 1 × Allison V-1710-39 V-12 liquid-cooled piston engine, 1,240 hp (920 kW)
- Maximum speed: 334 mph (538 km/h, 290 kn) at 15,000 ft (4,600 m)
- Cruise speed: 308 mph (496 km/h, 268 kn)
- Range: 716 mi (1,152 km, 622 nmi) at 70% power
- Service ceiling: 29,100 ft (8,900 m)