Republic P-47 Thunderbolt

The P-47 was produced in greater numbers than any other American fighter aircraft. Between 1941 and 1945 a total of 15,683 of this massive fighter were produced. It was also the largest and heaviest single piston engined fighter aircraft ever produced.

Somewhat ironically, the P-47 had begun life as a light-weight interceptor powered by an Allison V-1710-39 liquid cooled inline engine, providing 1,150hp. This design had been proposed by Alexander Kartveli, Republic’s chief designer, in August 1939. However, events in Europe soon began to demonstrate weaknesses in the original specifications. More guns, more armour and self sealing fuel tanks were amongst the changes dictated by the fighting over Poland and France. Each change reduced the performance of the light P-47.

Kartveli’s response was to propose a much heavier radial powered aircraft. This would be a much larger development of his earlier XP-44 and P-43 designs. This design was first proposed in June 1940. In August it officially replaced the light weight XP-47. Finally, in September 1940 the existing order for P-44s were scrapped in favour of the new Thunderbolt. Like the P-44 the P-47 used a turbo-supercharger, located in the tail, to provide increased power when needed.

The prototype XP-47B first flew on 6 May 1941. That test flight revealed some minor problems, but also demonstrated that the basic design was sound. The Thunderbolt still had a great deal of prejudice to overcome. It was a very different aircraft to any fighter then in service. It was twice as heavy as the Supermarine Spitfire, and would require a very different style of combat.

The Thunderbolt soon gained the nickname “Jug”, from its resemblance to a moon-shiner’s whiskey jug. On its arrival in Britain this nickname was apparently misunderstood as being short for “Juggernaut”.

Every time a new fighter with increased speed but reduced manoeuvrability appeared during this period the same lessons had to be learnt. The P-47 was not a good dogfighter – just about every aircraft it would fight against could out turn it. However, it was very fast at high altitude and could dive faster than any other aircraft then in the air. This allowed the P-47 pilot to “bounce” his opponents, just as German fighter pilots had learnt to bounce their slower but more manoeuvrable opponents over Poland. The P-47 was much better above about 20,000 feet, making it an ideal bomber escort for the high flying aircraft of the 8th Air Force.

The success of the Thunderbolt owed a lot to lucky timing. It had been designed as an interceptor, at a period when the American bomber chiefs still believed in the concept of the self-supporting bomber formation. Long range bomber escorts were not then a priority. The Thunderbolt would have made a poor interceptor. Early versions had the same limited range as the Spitfire. A short range interceptor needed to be able to climb very quickly, to catch up with high flying enemy aircraft. Early P-47s were terribly slow in the climb. However, by the time the aircraft was available in significant numbers, the need for interceptors over Britain was much less urgent, but long range bomber escorts were increasingly in demand.

The Thunderbolt divided opinions at the time. Many pilots, used to the more maneuverable Spitfire in Europe or the P-38 in the Pacific did not like the aircraft. However its good features soon won over many. It was a very robust aircraft, suffering an incredibly low loss rate of only 0.7% during its combat career. Its eight .50in machine guns made it the most heavily armed American fighter of the war. Its very high diving speed allowed the careful Thunderbolt pilot to choose when he entered combat, and just as importantly allowed him to break away at will.

By the end of the war the P-47 had become an excellent ground attack aircraft. It could carry up to 2,500lbs of bombs or rockets, not as heavy a load as some of the very best fighter bombers of the war, but still impressive. Its solid construction and radial engine made it much more survivable than many other ground attack aircraft. In the European theatre the Thunderbolt was estimated to have destroyed 6,000 tanks and armoured vehicles and 9,000 railway locomotives, playing a crucial role in the allied advance across Europe after D-Day. Despite its ungainly appearance, the Thunderbolt had proved itself to be one of the best fighter aircraft produced during the Second World War.

Air War Index - Air War Links - Air War Books

How to cite this article: Rickard, J (13 May 2007), Republic P-47 Thunderbolt,

Help - F.A.Q. - Contact Us - Search - Recent - About Us - Privacy