Aviation of Word War II
Aircraft BI (BI-1) (Bereznyak and Isaev) is an experimental fighter-interceptor with a liquid-propellant rocket engine. The aircraft had an unusually small size: a wingspan of 6.48 m, a length of 6.4 m and a wing area of only 7.0 m². Armament: two guns ShVAK-20 with 90 shells and 38 kg of bombs. The D-1 A-1100 engine by Leonid Stepanovich Dushkin and Vladimir Arkadevich Shtokolov with a thrust of 1100 kgf that had practically been achieved by that time.
The designers of the BI aircraft, engineers Alexander Yakovlevich Bereznyak and Alexei Mikhailovich Isaev, employees of the Design Bureau V.F. Bolkhovitinov. Bereznyak was the head of the brigade of mechanisms, Isaev was the head of the engines. In the early spring of 1941, on their own initiative, they began to develop a draft design for a new type of fighter with a rocket engine, which promised a speed of 800 km / h or more.
With the beginning of the war, they offered Bolkhovitinov to submit a draft resolution. A letter was sent from the institute (where the engines were made) and the factory, which was signed by seven participants, including aircraft designers Bereznyak and Isaev, engine designer Dushkin, factory director Bolkhovitinov and chief engineer of the institute Kostikov. The letter was sent on July 9, 1941, and soon everyone was summoned to the Kremlin. The proposal was approved, accepted, A.I. Shakhuripym and A.S. Yakovlev drafted a resolution, which was approved a few days later. Based on it, there was a revised order for the NKAP. The issue period was set at 35 days (instead of three months, as A. Ya. Bereznyak and A. M. Isaev wanted).
All OKB Bolkhovitinov was declared "in the barracks", they worked without leaving the factory for a month and ten days. By September 1, the first copy of the aircraft was sent for testing to the NKAP. They built the plane almost without detailed working drawings, drawing its parts in kind on plywood, according to the plazas. This was facilitated by the small size of the aircraft. Purges were made in the full-scale TsAGI pipe (leader G.S. Byushgens).
Aircraft structure - solid wood. The fuselage is a plywood monocoque covered with canvas. Wing - multi-spar with plywood sheathing, plumage - also, plywood 2 mm. Rudders and ailerons with fabric covering. Cylinder tanks are welded from chromansil. The engine is located in the extreme rear part of the fuselage. Chassis with small wheels - 500 × 150 mm, pneumatically retracted into the wing in the direction of the axis of the aircraft. In practice, the tests were carried out to a large extent in winter - on skis that were removed. Wing - caisson - between two box-shaped spars there is a solid thick load-bearing skin formed by shelves of a dozen intermediate lighter spars. Schrenk landing flaps, lowered by 50 °, and very small ailerons - only 1/3 of the half-span of the wing. The tail unit is normal, the stabilizer is attached to the fuselage and fin. During blowdowns, small round “washers” of vertical tail were added to it. Crutch - non-orienting, in a fairing.
The overall design and production performance was average, there were also fragile places (due to haste).
The weight of the empty experimental BI-1 aircraft is 790 kg, the military series is 805 kg The weight of the airframe is 462 kg, including: fuselage - 182 kg, wing - 174 kg, plumage - 30 kg, landing gear - 60 kg, controls - 16 kg; engine weight - 48 kg.
In the fuselage were tanks for compressed air weighing 22.4 kg, tanks for kerosene weighing 31.2 kg and tanks for nitric acid - about 80 kg. The mass of various equipment is about 20 kg.
ShVAK-20 guns (with 45 rounds each) were installed in the forward fuselage under a removable (with locks) cover. The armament aircraft was a full-fledged fighter: there was electric fire control, pneumatic reloading, there was a cassette for small bombs with a total weight of up to 38.4 kg. The mass of the weapon is 76 kg, bulletproof glass is 6 kg.
Full load - 860 kg, including: pilot - 90 kg, acid - 570 kg, kerosene - 135 kg, ammunition - 19.6 kg, bomb load - 38.4 kg.
The takeoff weight of the first experimental aircraft is 1650 kg, the military one is 1683 kg.
Destructive overload 9, with a mass of 1100 kg (with the consumption of part of the fuel) - 13.5.
At the airfield, first of all, jogging and approaching in tow were started, and the power plant was still being worked out. There were many novelties and difficulties here, especially with nitric acid corroding tanks and wiring. A number of safety measures were required due to the harmfulness of even nitric acid vapors to humans, there were cases of burns. But this was more or less managed.
The aircraft without engines was tested by Boris Nikolaevich Kudrin. In 15 flights, all characteristics were removed. Before the evacuation on October 16, 1941, nothing more could be done. When everything was relocated to the Urals, test pilot Grigory Yakovlevich Bakhchivandzhi was assigned to the aircraft with the engine installed on it. BN Kudrin was prevented by illness. After the complete adjustment of the power plant and other improvements, it was possible to start flying with the engine (it was received in April 1942). The test of the engine on the plane was on April 27th.
On May 15, 1942, Captain Bakhchivandzhi (a well-known front-line pilot who had already worked as a test pilot before the war) performed the first flight on the BI-1. In the winter of 1942, Lieutenant Colonel Konstantin Afanasyevich Gruzdev, an outstanding front-line pilot, performed one flight on the BI-1. In this flight, when the landing gear was extended before landing, one ski came off, but Gruzdev landed the plane safely.
Flight data turned out: maximum speed - about 800 km / h (estimated 1020 km / h at an altitude of 10,000 m), rate of climb near the ground - up to 82 m / s, flight time - 7 minutes, takeoff run - about 400 m, climb time 5000 m - 30 s, acceleration to a speed of 800 km / h - 20 s, landing speed - 143 km / h.
The flight on the BI-1 was difficult, and not only out of habit. It was possible to sit on it only after the development of fuel, the proximity to nitric acid under high pressure was unpleasant, sometimes breaking out through the joints of the wiring, and even through the walls of pipes and tanks. These damages had to be repaired all the time, which greatly delayed the flights that continued throughout the winter of 1942-1943. During them, G. Ya. Bakhchivandzhi died on March 27, 1943, when the plane went into a dive from level flight, from which it could not get out. The reason became clear only later. The fault was a straight (non-swept) wing, which has the effect of dragging into a dive at speeds of 900 km / h or more.
A military series of eight BI-1 aircraft was built (they were also called BI-2). B. N. Kudrin flew one of them upon his return to Moscow, there were no more flights. There was an attempt - incomplete - on one of the aircraft to make the cockpit hermetic by pasting all the seams with rubber strips.
It soon became clear that the BI aircraft as a fighter could not be accepted because of the excessively short flight duration, which was not covered by a one and a half times superiority in speed. The BI plane served to gain experience in this kind of work - in other projects of fighters with liquid propellant engines and in installations of liquid propellant engines on piston aircraft as temporary flight boosters.
In 1948-1949. A. Ya. Bereznyak had a project of an interceptor fighter with a three-chamber rocket engine (his own) with a thrust of 10 tons plus an AM-5 engine with a thrust of 2 tons for returning to the airfield and landing. A speed corresponding to Mach 1.8 was expected. The climb time was 20 km in 20 minutes and the range was 750 km.
The project was not implemented.