YAK 55

The design was given to Slava Kondratiev, then the leading light aircraft designer in Russia and the result was the Yak-55.  The aircraft has a thick totally symmetrical wing, which gives great strength. The aircraft is otherwise of conventional monocoque all- metal construction.

The prototype flew in May 1981 and was shown to the West in 1982. However, the Russian Team wasn’t equipped with ‘55s until 1984, when it immediately won the World Aerobatic Championship.

Yak-55M

By the middle of the 1980s, Sukhoi had brought out the all-composite SU-26, and Yakovlev were spurred on to produce an aircraft with yet greater performance.  Many feel that the result, the Yak-55M, was somewhat of a technological blind alley, since it reduced the wingspan of the ‘55, which succeeded in a higher rate of roll but at the expense of increased induced drag.   Therefore in a competition sequence, although the ‘55M will roll faster, it will actually lose more height than the ‘long-wing’ ‘55.

Aerobatic

We say that the ‘55 will give 85% of a Sukhoi’s performance at 40% of the cost, which is a reflection of the aircraft’s capability. It is very tough, rugged and with very good performance.  It has quite a lot of drag because of its thick (but of course very strong) wing, but of course a lot of power to overcome this.

The cockpit is roomy (but a bit short in leg length) and the aircraft is a delight to fly and in particular is extremely easy in its ground-handling, even for relatively low-time tail-wheel pilots.

The aircraft has been relatively free of Service Bulletins (Airworthiness Directives), and has proved exceedingly effective in competition at all levels.  Today, the ‘55 is outclassed in Unlimited competition, but is probably the best value for money in terms of Advanced competition.

Modifications

The obvious capabilities of the aircraft and its success in use, together with the relatively large numbers built (some 250) have meant that there are relatively few modifications that owners do, or indeed are needed.  However:

• For some reason original ‘55s did not have an air-charging system.  This was fine when the aircraft operated only at Russian Airfields, but for normal Western use and to make the aircraft totally autonomous, it is necessary for it to have an air compressor and the normal air charging system, which on importer fits to all ‘55s.
  

• The ‘55 has two wing tanks, but for some reason only has a fuel gauge in one of them – one importer therefore always fit gauges on both fuel tanks in case there is a problem with fuel-feed.
  

• Early ‘55s had very weak mechanical brakes and we modify all ‘55s we sell to much more powerful modern hydraulic brakes.

Operating cost

Because of its rugged construction and proven mechanics the ‘55 is a reliable and relatively cheap aircraft to operate.  

SP-55M

Slava Kondratiev, the original Yak-55 designer, realised in the late 1990s that the Yak-55 could be significantly enhanced with a variety of modifications, which he has done, to produce a totally new aircraft, the SP-55. This incorporates all the proven structural components of the ‘55, but with a variety of improvements; composite flying controls; lighter weight; improved manoeuvrability etc. The result is an aircraft that will come close to a Sukhoi SU-3l when equipped with the M14PF 400hp engine, but well under half its price. Production of this aircraft is continuing at the Arsenyev factory in the Russian Far East. We can provide all information if needed, and usually have an SP-55M demonstrator in stock.

Performance

Empty weigh 640kgs (1410lbs)
Maximum speed 320kph (205mph)
Rate of climb 960m per minute (3150ft)
Rate of roll 345° per second
Take-off run 125m
Landing run 175m