SUKHOI
P-l
Suk hoi PI
Purpose: To create a more capable interceptor for the IA-PVO (manned airdefence aviation). Design Bureau: OKB-51 of P O Sukhoi, Moscow. In December 1954 the MAP (Ministry of Aviation Industry) requested studies of a new fighter, called P (Perekhvatchik, interceptor). Studies embraced single- and two-seat aircraft armed with every combination of guns, rockets and guided missiles, and with nine types of afterburning turbojet. On 19th January 1955 the Council of Ministers ordered from Sukhoi prototypes of the P-l powered by a single AL-9 and the P-2 powered by two VK-11 engines. Mockups were reviewed in late 1955, and construction of the P-l was authorised, the P-2 being abandoned in early 1956. OKB-51's factory constructed the single 164
P-l from August 1956. At a late stage it was recognized that the chosen engine would not be ready in time, and the aircraft was redesigned for an engine of rather less thrust in order to get it airborne. It was taken to the OKB's flight-test station on 10th June 1957, and was flown there by Nikolai Korovushkin on 12th July 1957. He was joined by Eduard Elyan, and Factory Testing was completed on 22nd September 1958. The intended engine never did become available, and Sukhoi failed to obtain an alternative (the R-15B-300 went instead to the T-37). The P-l was transferred to the experimental category and finally abandoned. Intended for a more powerful engine, the Lyul'ka AL-9 with an afterburning thrust of 10 tonnes (22,046Ib), the P-l was thus larger than all the other Sukhoi aircraft of its generation. The wing was scaled up from the earli-
Three views of P-1.
er PT-8, which had introduced the feature of a dogtooth discontinuity in the leading edge to create a powerful vortex at large angles of attack to keep flow attached over the upper surface. Unlike the PT-8 the leading-edge sweep was reduced at a point ahead of aileron mid-span from 60째 to 55째. Otherwise the wing followed Sukhoi practice with rectangular slotted flaps, sharply tapered ailerons terminating inboard of the tips, landing gears retracting between Spars 1 and 2 and integral tanks ahead of Spar 1 and between Spars 2 and 3. The large fuselage was exceptionally complex. In the nose was the single dish antenna of the Pantera (panther) search and fire-control radar, with the multifunction instrumentation boom projecting from the tip. With this aircraft Sukhoi gave up