Flying Forever - Vakhmistrov Parasite Fighters

Vladimir S. Vakhmistrov gained Soviet air force approval in 1931 to carry out some of the earliest experiments with parasite fighters to be carried by bomber aircraft following his proposal of the idea in mid-1930. The concept was not only to provide a defensive escort for bombers over distances normally beyond escort range, but also to enable offensive sorties by the parasite aircraft, and long-range suprvision of air space.

The first unit was coded Z-1, and consisted of a Tupolev TB-1 carrying a Tupolev I-4 above each wing, loaded on the ground with the help of a wooden ramp. Locks on the main undercarriage were released by the parent aircraft's second pilot. A further support was attached to the tail of the fighter.

The Z-1 Samolet Zvena ('aircraft-aircraft group') combination was first flown on 3 December, 1931, and whilst in the excitement the main gear was released prematurely, the fighter pilot recovered the situation. The second aircraft released smoothly, and the unit made a number of successful test flights.

The next development, the Z-1a, retained the TB-1, re-equipped with two Tupolev I-5s. The Z-2 used a Tupolev TB-3 with an I-5 above each wing and one over the fuselage. It first flew in September 1933. The Z-2 appeared in August 1934, using the four-engined TB-3 bomber as carrier aircraft, with three I-5s being attached, one above the parent aircraft's fuselage. The Z-3 saw the first attachment of under-wing fighters, in autumn 1934; a TB-3 with two I-Z monoplanes.

With the Z-5 came accommodation of a modified Grigorovich I-Z fighter carried on a trapeze below the fuselage. In-flight recovery of fighters to brackets on the wings, the attachment method used until this point, was impracticable; but recovery was successfully conducted using the trapeze on 23rd March, 1935, and was the first in the world that this had been accomplished beneath a fixed wing aircraft.

Next in the series was the Z-6, which consisted of a TB-3 with a Polikarpov I-16 beneath each wing. The Z-7 was similar, but with a third I-16 in the under-fuselage trapeze position.

The most ambitious version was the Aviamatka, a TB-3/AM-34 which, in 1935, carried an I-16 above each wing and an I-5 below. In flight, it lowered a trapeze from under the fuselage to collect an I-Z fighter. All five fighters would be released simultaneously.

In 1937 some senior officers who had sponsored the project were arrested, and the project was stopped. Engineer Vakhmistrov put together a new version of the aircraft-aircraft unit, a variation on the Z-6, the TB-3 having newer engines, and carrying two I-16 dive bombers, known as SPBs.

A squadron of six TB-3/AM34s and twelve SPBs was formed in the last months before Russia went to war with Germany, and in summer 1941, a Zveno group took off from an airfield on the Black Sea to attack the Negru Voda bridge across the Danube, in Rumania. The SPBs separated near the target and attacked with their 250 lb. bombs, then escorted the parent aircraft home. This was the first and only offensive use of the parasite aircraft unit.