One other version of the M-4 ‘Bison’ is known, a test-bed aircraft powered by four D-15 turbojet engines each of 13000kg thrust and designated 201-M.

This was used in September 1959 to establish a number of payload-to-height records by lifting a payload of 10,000 kg (22,046 lb) to 50,253 ft (15,317 m) and the weight of 55,220 kg (121,480 lb) to 2000 m (6,561 ft).

Originally identified in 1982 by US reconnaissance satellites as the ‘Ram-M’ single-seat high-altitude reconnaissance aircraft, and later codenamed ‘Mystic’ by NATO, the twin-boom straight-wing jet, was publicised as a high-altitude research aircraft able to carry around 1500kg of sensors, existing in two versions.

The first of two prototype aircraft, designated M-17 Stratosfera (‘Mystic-A’), first flew in 1988 and are powered by a single 68.6kN thrust Rybinsk RD-36-51V turbojet developed from the Tu-144 SST powerplant.

The M-55 Geofizika (‘Mystic-B’), has two 49kN thrust Perm/Soloviev PS-30-V12 turbojets mounted side-by-side behind a raised cockpit installed in a longer nose, together with a reduced span wing.
The M-55 ‘Mystic-B’ differs from the first M-17 Stratosfera in having a longer jetpipe, shorter engine intakes, a reprofiled nose and an undernose FLIR turret.

The role of the ‘Mystic-B’ is described as environmental sampling missions or high-altitude research and endurance in this role is claimed as over 4 hours loiter capability at 20000m. A further variant of the M-55 is reported to be under development with wingroot mounted engines in stalled in a conventional fuselage carrying a sweptback tail unit.

Two ‘Mystic-A’ prototypes were followed by two ‘Mystic-B’ and two pre-production ‘Mystic-Bs’ were flying by 1992.

Gallery

Engines: 2 x Soloviev PS-30-V12, 49kN
Wingspan: 37.47 m / 122 ft 11 in
Length: 22.87 m / 75 ft 0 in
Height: 4.83 m / 15 ft 10 in
Cruise speed: 750 km/h / 466 mph
Ceiling: 21000 m / 68900 ft
Crew: 1

After directing CAHI (TsAGI) from 1960, Myasishchev returned to OKB No 23 in early 1978 in order to study how a 3M strategic bomber might be modified to convey large space launchers and similar payloads. In particular an aircraft was needed to transport to the Baikonur launch site four kinds of load: the nose of the Energiya launcher; the second portion of Energiya; the Energiya tank; and the Buran spacecraft, with vertical tail and engines removed. These loads typically weighed 40 tonnes and had a diameter of 8m. Myasishchev had previously calculated that such loads could be flown mounted above a modified 3M bomber. He died on 14th October 1978, the programme being continued by V Fedotov. While design went ahead, three 3M tanker aircraft were taken to SibNIA (the Siberian State Research Instiutute named for S.A.Chaplygin) and put through a detailed structural audit preparatory to grafting on a new rear fuselage and tail, and mountings for the external payload. The modified aircraft were designated 3M-T. All were rebuilt with zero-life airframes and new engines, but initially without payload attachments. One was static-tested at CAHI while the other two were completed and flown, tne first on 29th April 1981. After a brief flight-test programme they were equipped to carry pick-a-back payloads, and in Myasishchev’s honour redesignated VM-T Atlant. The first flight with a payload was made by A.Kucherenko and crew on 6th January 1982. Subsequently the two Atlant aircraft carried more than 150 payloads to Baikonur.

The most obvious modification of these aircraft was that the rear fuselage was replaced by a new structure 7m longer and with an upward tilt, carrying a completely new tail. This comprised modified tailplanes and elevators with pronounced dihedral carrying inward- sloping fins and rudders of almost perfectly rectangular shape, with increased total area and outside the turbulent wake from any of the envisaged payloads. Less obvious was the fact that, even though the maximum take-off weight was less than that for the bomber versions, the airframe was strengthened throughout.

As time between overhauls was not of great importance the original four VD-7B engines were replaced by the VD-7M. These were RD-7M-2 engines, originally built for the Tu-22 supersonic bomber with afterburners and variable nozzles, which had had the afterburner replaced by a plain jetpipe and fixed-area nozzle. Thrust was 11,000kg. These were in turn replaced by the VD-7D, rated at 10,750kg. Each aircraft was fitted with 14 attachment points above the fuselage and on lateral rear-fuselage blisters for the four different kinds of supporting structure, each being specially tailored to its payload. They were also equipped with a modified flight-control and autopilot system. The forward fuselage was furnished with work stations for a crew of six.

The aircraft were given civilian paint schemes, one being registered RF-01502 and the other being RF-01402 and fitted with a flight-refuelling probe. To support their missions the PKU-50 loading and unloading facility was constructed at spacecraft factories, including NPO Energiya at Moscow Khimki, and at the Baikonur Cosmodrome. These incorporated a giant gantry for carefully placing the payloads on the carrier aircraft. Despite the turbulent aerodynamics downstream of the external payloads, this dramatic reconstruction proved completely successful.

Max take-off weight: 136400 kg / 300712 lb
Max. speed: 600 km/h / 373 mph
Cruise speed: 540 km/h / 336 mph
Ceiling: 9500 m / 31150 ft
Range w/max.fuel: 3000 km / 1864 miles
Range w/max.payload: 1500 km / 932 miles
Crew: 6