Obituary: P. A. Soloviev

In the Soviet Union it was usual for aircraft and their engines to be designated according to the leader of the design team. P. A. Soloviev remained for many years almost unknown in the Western world, because most of his engines were designated by a simple letter D, from dvigatel ("engine").

Born in 1917, Pavel Aleksandrovich Soloviev (pronounced "Solovyov") was from childhood interested in everything mechanical. From high school he entered the Aviation Technological Institute at Rybinsk (today Andropov). He graduated with distinction in 1939, and joined the OKB (experimental construction, or design, bureau) of Arkadiya D. Shvetsov at Perm.

Shvetsov was the first aero-engine designer to set up his own OKB in the Soviet Union. His firstborn, the simple M-11 radial engine of 100hp, remained in production over 40 years, more than 130,000 being built.

But by the time Soloviev joined there was a need for engines of far greater power for fast fighters and bombers. Soloviev played a leading role in developing the M-82 (redesignated in Shvetsov's honour as the ASh-82 in 1941), an air-cooled radial in the 1,500-2,000hp class. It was one of the most important engines of what Russians call the Great Patriotic War, and over 70,000 of them were built.

In 1946 Soloviev played a leading part in the development of the most powerful piston engine ever to be installed in an aircraft, the ASh-2K of 4,700hp. He also worked on many other engines, such as the ASh-21 of 550-700hp, which is still in use in aeroplanes and helicopters.

In 1953 Soloviev succeeded Shvestov as chief constructor of the Perm OKB. He recognised that, by this time, aircraft requiring high power would use not piston engines but gas turbines. Some piston-engine designers, especially in the Western world, found it hard to learn the very different technology, with exceedingly complex problems of aerodynamics and combustion and a range of new materials. Soloviev accepted the challenge with enthusiasm.

He immediately began the design of the first turbofan to go into service and a turboshaft engine of unprecedented power for a giant helicopter. Soloviev had studied the writings of Frank Whittle, who had pointed out that the propulsive efficiency of a jet engine would be increased if the airflow through it could be increased and the jet velocity reduced. Accordingly he produced the D-20P, a neat turbofan with a mass flow of 293 pounds per second and take-off thrust of 11,905 pounds. To the astonishment of Western designers, this beat their turbofans into service in the Tu-124 jetliner on 2 October 1962.

The turboshaft engine was the D-25V, which delivered 5,500hp at a time when the most powerful helicopter engine in the Western world was a piston engine rated at 1,900hp. Two D-25Vs made possible the Mi-6 helicopter of 1957. Over 800 of these monsters were built, and even today the Western world has no helicopter with anything remotely similar in size and capability.

Having cut his teeth with these two engines, Soloviev went from strength to strength. The D-30 designation was, with typical Russian mentality, used for two completely different families of engines, one (for the Tu- 134 jetliner) in the 15,000-pound thrust class and the other (for various big jet transports) rated at 24,000-26,500 pounds. To confuse things still further, the derived D-30F6 is a monster fighter engine, with an afterburner, with a combat thrust rating of 41,843 pounds.

Soloviev's final achievement was the PS-90, a giant turbofan of high bypass ratio for advanced passenger and cargo transports. A family of PS-90 engines are now flying, in the 35,000lb class. What their designer did not expect is that in today's former Soviet republics they are having to compete with Western engines.

Soloviev gained a professorship in 1960, was made a Hero of Soviet Labour in 1966, was appointed a doctor of of technical science in 1973 and a corresponding member of the USSR Academy of Sciences in 1981. Also in 1981 he reached the supreme industrual rank of General Constructor. He retained this until he retired in 1989, handing over to Yuri E. Reshetnikov.

Pavel Aleksandrovich Soloviev, aeroplane engine designer: born 1917; died Perm, Russia 13 October 1996.