The M(G)-19 “Gurkolyot”

Another idea for an SSTO spaceplane emerged at the Strategic Rocket Forces’ NII-4 research institute. It was the brainchild of Oleg Gurko, who had been working out ideas for such systems since the late 1940s. The novelty in Gurko’s plan was a hydrogen scramjet that would suck in air heated by the exhaust of a liquid-fuel rocket engine placed in front of it. In the 1960s he approached both Mikoyan and Myasishchev, who both showed interest in building a vehicle using such a propulsion system. However, the barriers between the Strategic Rocket Forces and the Ministry of the Aviation Industry proved too high.

It was not until after the approval of the US Space Shuttle in the early 1970s that Soviet top brass started showing some interest in Gurko’s ideas. On 10 October 1974 the Minister of the Aviation Industry and the Air Force Commander-in-Chief signed an order allowing Myasishchev’s Experimental Machine Building Factory (EMZ) to work out “technical proposals’’ for an SSTO using Gurko’s propulsion system under a program called Kholod-2 (“Cold-2”). Placed in charge of the project within EMZ was A. Tokhunts, one of Myasishchev’s deputies, and the leading engineer was I. Plyusnin. Development of the propulsion system was entrusted to the Kuznetsov design bureau in Kuybyshev, the same bureau that had built the engines for the lower stages of the N-1 rocket. Gurko, now employed by the TsNII-50 R&D institute that had split off from NII-4 in April 1972, continued to provide technical support. Within EMZ the project was known as “Theme 19’’ and the SSTO itself was designated

M-19. It has also been referred to as MG-19 (“G” for Gurko) and was affectionately known as “Gurkolyot”.

In its final design the M-19 was a 69 m long triangular-shaped lifting body with small aft and front-mounted wings and two fins. Having a take-off mass of 500 tons, it was capable of inserting a 40-ton payload into low Earth orbit. There was also an alternative plan for a Buran look-alike vehicle with big delta wings and a single vertical stabilizer. Having the same take-off mass as the primary design, it would have a payload capacity of just 30 tons.

The M-19 had an impressive cross-range capability of 4,500 km and could significantly change its inclination by making dips into the atmosphere down to 50-60 km. Thermal protection was provided by carbon-carbon material and tiles. Situated in the nose was the crew compartment, which could be jettisoned from the vehicle in case of an emergency. It consisted of a flight deck and living compartment and was designed to carry a crew of between three and seven. Behind the crew compartment was a 15 x 4 m payload bay, equipped with an airlock/docking system and a remote manipulator arm.

Installed behind the payload bay was a big, removable tank containing liquid hydrogen for the vehicle’s propulsion system. The latter was made up of a nuclear engine in the aft section of the vehicle, a pair of two-spool turbojet engines, and a set of hypersonic scramjet engines mounted on the underside of the aft fuselage. The propulsion system was adapted from Gurko’s original proposal by the introduction of an on-board nuclear reactor that would heat up the air entering the turbojet and scramjet engines to very high temperatures. This would allow the air to escape from the nozzles at very high speeds with little combustion taking place, making it possible to save hydrogen for later stages of the orbit insertion process. The turbojet and scramjet engines would be used to accelerate the M-19 to a speed of Mach 16 and carry it to an altitude of 50 km. At that point the nuclear engine would kick in to place the ship into orbit.

The M-19 was billed as a multi-purpose system, capable of performing routine space transportation tasks, missions in the interests of science and the national economy, as well as reconnaissance and offensive missions. One big advantage of the SSTO was that it required no staging during launch, meaning that it had an almost unlimited number of launch azimuths.

EMZ was aiming for a step-by-step approach in the development of the M-19. This would include test flights of several “flying laboratories” to test the nuclear and scramjet engines, drop tests and re-entry tests of M-19 models, and the construction of an experimental hypersonic airplane that could act as a long-range bomber with a range of up to 12,000 km or a launch platform to place into orbit 40-ton payloads. The SSTO itself was expected to be ready for its first flight in 1987-1988.

Myasishchev perfectly understood the technical challenges posed by such a system and was well aware it wouldn’t be ready to fly until many years after the Space Shuttle. However, since the Soviet Union was already several years behind in the development of a Space Shuttle response, he reasoned it would be better to start work on a much more advanced and capable system straightaway rather than build a copy that itself would be upstaged by the Space Shuttle by several years.

Despite the futuristic nature of the M-19, Myasishchev was not hampered by his “boss” Pyotr Dementyev, the Minister of the Aviation Industry, albeit more for political reasons than anything else. Just as he did with Spiral, Dementyev seems to have considered the M-19 a convenient tool in his arguments with MOM. Dementyev was wary of getting involved in NPO Energiya’s (read: MOM’s) Space Shuttle “copy”, fearing that if his aviation design bureaus were assigned to the project, some of them would eventually be transferred to MOM. By tacitly support­ing the M-19, he hoped to drag out the decision-making process leading to the approval of a Space Shuttle response.

Work on the project continued even after Myasishchev’s EMZ was absorbed by NPO Molniya to work on Buran in February 1976. On 25 May 1976 the Military Industrial Commission decided to continue basic research on the SSTO spaceplane. Research in support of the M-19 was conducted by leading aviation institutes such as TsAGI, TsIAM, and ITPM. EMZ drew up plans to fly an experimental Lyulka liquid-hydrogen engine on an Ilyushin Il-76 airplane, mainly to test the techniques required to store liquid hydrogen at cryogenic temperatures. After Myasishchev’s death in October 1978, this work was transferred to the Tupolev bureau, where it was successfully completed using the Tu-155.

Myasishchev’s death was a major setback for the Gurkolyot. Nevertheless, work on the project seems to have continued at some level until the collapse of the USSR. Between 1978 and 1988 it was mentioned in three more VPK decisions and even in two government/party decrees. While the M-19 may have been considered a serious contender to counter the Space Shuttle before 1976, it quickly moved into the background once work on Energiya-Buran got underway in earnest. From then on it was probably seen as no more than a promising design for a second-generation shuttle vehicle.

One problem with further research on the M-19 was that it had to be done by organizations already preoccupied with Buran. Although there were government orders for NPO Molniya and TsNIIMash to conduct research on the M-19, there was very little enthusiasm for it. There does seem to have been at least some support for it from Boris Gubanov after he was appointed chief designer of the Energiya – Buran system in 1982. The M-19 was also hampered by interdepartmental squabbling between MOM and MAP, on the one hand, and the Strategic Rocket Forces and the Air Force, on the other hand.

Another problem with the M-19 was the use of a nuclear reactor and propulsion system, which posed safety risks both to the crew and the general public, even though designers went to great lengths to make it as safe as possible. However, the biggest showstopper for the M-19 must have been that few believed it was technically feasible, and perhaps rightly so, because even today, thirty years on, a vehicle of this type remains no more than a distant dream [19].