The Polikarpov TIS was a long range heavy fighter of which two prototypes were built but that never entered production. The aircraft was designed in response to a Red Air Force requirement for a long range escort fighter, at least partly inspired by the publicity being given in Germany to the Bf 110. The specifications were issued to Polikarpov's design bureau in November 1938, but serious work on the new aircraft didn't begin until the second half of 1940. The design team was led by Mikhail Yangel, a post-war designer of space craft.
His team produced a twin-engined two-seat low wing monoplane, with a cigar-shaped fuselage. The prototype was armed with four SkKAS machine guns, carried in the forward part of the fuselage, although production aircraft were expected to be armed with cannon. The aircraft could also carry two rear firing machine guns, one mounted in the back of the cockpit and the other in the floor of the fuselage. The aircraft had a twin-fin tail.
The first prototype - TIS(A) - was powered by two 1,400hp Mikulin 12-cylinder AM-37 engines, and was expected to reach a top speed of 394mph at 24,250ft. It made its maiden flight in September 1941 at Moscow, and performed rather disappointingly, only reaching 344mph at 19,000ft. The engines were largely at fault, although the aircraft also suffered from poor directional stability. Flight tests continued at Novosibirsk, and the stability problems were solved, but the AM-37 engine remained unsatisfactory, and work came to a halt.
Development of the TIS resumed in the second half of 1943, as the TIS(MA). This version was to be powered by two 1,900hp AM-39 engines, and was much more heavily armed. Four 20mm ShVAK cannon were carried in the nose, and two 45mm cannon were to be installed in the wing centre section. The lower rear firing maching un was removed, but a more powerful UBT machine gun was installed in the rear upper position.
The prototype TIS(MA) had to be built with low-altitude AM-38F engines, which performed best below 5,400ft. Even so the aircraft's low altitude speed was good, and it was estimated that it would be able to reach 403mph at 23,500ft with the correct engines. Its maiden flight came late in 1943 and flight tests were carried out from June-September 1944, but in the summer of 1944 Polikarpov died, and work on his designs came to a halt. The prototype TIS(MA) survived until 16 September 1944 when it was badly damaged in a belly landings and not repaired.
Wing span: 50ft 10in
Length: 14ft 0in
Empty Weight: 12,786lb
Gross Weight: 17,283lb
Max Speed: 332mph at 22,950ft
Service Ceiling: 33,600ft
Armament (planned): Two 20mm cannon and six 7.62mm machine guns