Sukhoi Su-27 P-42

In the early 1980s the Su-27 programme was accumulating delays and accidents: three serious mishaps in the early flights of the T-10S prototypes, one of them fatal. According to the Spanish-language source, against that background, and to win political backing, it was decided to prepare the third prototype of the T-10S configuration to beat a series of records then held by a similarly modified F-15. The resulting aircraft was officially designated P-42 and nicknamed the "Streak Flanker" in the West, a direct reference to the F-15 "Streak Eagle" that in 1975 had set the time-to-height records it was meant to beat.

The preparation followed the same recipe as the Streak Eagle: remove everything that did not help the aircraft climb. Armament, radar and all operational equipment were taken out; so were the fin tips, the tail boom and the wingtip launch rails. The composite radome was replaced by a lighter metal one. The paint was stripped, the surface polished and every drag-producing gap and joint sealed. According to the English-language source, this brought the weight down to 14,100 kg. The engines were modified to deliver an extra 1,000 kg of thrust each, bringing the thrust-to-weight ratio to almost 2:1, far above that of the production fighter. A curious detail: when the records were registered with the FAI in 1986, the Soviet side gave the engine designation as "R-32", which led the Western press to attribute the engines wrongly to the Tumansky bureau, even though the same source admitted there was reason to believe that the "P-42" was a specially prepared version of the Su-27.

The series of records began on 27 October 1986, when test pilot Viktor Pugachev climbed to 3,000 m in 25.4 seconds. On 15 November 1986 the same pilot reached 6,000 m in 37.1 s, 9,000 m in 47 s and 12,000 m in 58.1 s. On 11 March 1987 test pilot Nikolai Sadovnikov, the man who in 1983 had saved a T-10S after part of its wing broke away, reached 15,000 m in 76 seconds. The campaign continued until 1988 and took several of the Streak Eagle's records; according to the English-language source, several of them, including time to climb to 3,000, 6,000, 9,000 and 12,000 m, still stood in 2019.

The P-42 was never an operational aircraft but a propaganda and technical-demonstration tool. Once the Su-27 was finally declassified in early 1989, the record aircraft joined the public displays: at the 1989 air festivals at Zhukovsky and Tushino, Pugachev flew the P-42 in an aerobatic display, in a programme that also paid tribute to test pilot Alexander Shchukin, who had died shortly before. The success of those festivals spurred the idea of a regular aerospace exhibition at Zhukovsky, the first of which, "Mosaeroshow-92", was held in August 1992 at the Flight Research Institute. As a piece of history, the P-42 demonstrated before the FAI the thrust and acceleration reserves of the Su-27 airframe even before the production fighter was shown in the West, at the 1989 Paris Air Show, where Pugachev performed the "Cobra" manoeuvre in public for the first time.