ENERGIYA COMPONENT TESTING

The lead research institute for aerodynamic, dynamic, and structural testing of launch vehicle components was the Central Scientific Research Institute of Machine Building (TsNIImash) in Kaliningrad. Studies of the aerodynamic behavior of the Energiya-Buran stack during various phases of the launch and also of the strap-ons after separation were conducted in several wind tunnels and saw the use of more than 80 scale models in about 11,000 experiments overall. Dynamic tests involved the use of 1: 10 and 1: 5 scale models of the Energiya-Buran system. Individual RD-0120 and RD-170 engines were subjected to vibration tests.

For structural testing of core stage components, the Russians were forced into a different strategy than NASA. The US space agency built full-size test articles of the External Tank’s LOX tank, LH2 tank, and intertank, which underwent individual structural load tests at the Marshall Space Flight Center in 1977. However, the Russians did not have the facilities to do the same with their core stage elements

and therefore elected to do their structural tests (called “21”) using smaller pieces of the tanks. These included top and bottom sections of the LH2 tank joined together, a half-size LOX tank, an intertank section with parts of the LOX and LH2 tanks attached, a tail section with a mock-up LH2 tank bottom section attached, and a shortened LH2 tank. All these sections were manufactured at the Progress plant in Kuybyshev and tested either there or at TsNIImash. For the TsNIImash tests, which also included thermal testing, the sections were transported from Kuybyshev to the Moscow area by barge, the same one used to transport Buran orbiters from Tushino to Zhukovskiy. Subsequently, they were picked up by heavy MI-10 helicopters and airlifted to Kaliningrad.

Another institute playing a key role in Energiya-Buran testing was the Scientific Research Institute of Chemical Machine Building (NIIkhimmash) at Novostroyka near Zagorsk (now Sergiyev Posad), some 100 km north of Moscow. Having origin­ated in 1948 as a branch of the NII-88 rocket research institute and independent since 1956, this remains the largest test facility for rocket engines on Russian territory.

It has over 50 test stands for rocket engines and their components and also several thermal vacuum chambers and other facilities for spacecraft testing. When it came to simulating conditions during launch, one of NIIkhimmash’s main tasks was to study the acoustic environment during lift-off. This was done using a test stand called SOM-1 in which a 1:10 model of Energiya-Buran sat on a simulated launch table and was lifted several meters above the ground by a special hydraulic system. Another facility at Nllkhimmash (“Stand R”) simulated the separation of the Blok-A strap-on boosters from the core stage using full-scale mock-ups of the boosters.

Also involved in simulating the lift-off environment was the Scientific Research Institute of Chemical and Building Machines (NIIKhSM), situated in Zagorsk itself. This had a test stand called SVOD, which featured another 1: 10 model of Energiya – Buran equipped with small solid-fuel rockets to mimic conditions during lift-off. NIIKhSM was also responsible for testing various launch pad systems such as the sound suppression water system and the fueling systems.

The Russians never carried out full-fledged fueling tests of core stage propellant tanks until full-scale models of the Energiya rocket were placed on the launch pad at Baykonur in the mid-1980s. This also differed from the situation in the United States, where NASA did fueling tests of complete External Tanks at the Marshall Space Flight Center in 1977. In order to save costs, the Progress factory only built a test stand designed to fill the tanks with liquid nitrogen at temperatures of —180°/—190°C, which was significantly lower than the —255°C required for liquid hydrogen [1].