| BOR-4S | |
|---|---|
 BOR-4S nº401 at MAKS Airshow in Zhukovskiy, 2005 | |
| General information | |
| Type | Uncrewed 1:2 scale re-entry test vehicle |
| National origin | Soviet Union |
| Manufacturer | NPO Molniya |
| Number built | 7 |
| History | |
| First flight | 5 December 1980 |
The BOR-4 (БОР-4 Russian: Беспилотный Орбитальный Ракетоплан 4, Bespilotnyi Orbital'nyi Raketoplan 4, "Unpiloted Orbital Rocketplane 4") flight vehicle is a scaled (1:2) prototype of the Soviet Spiral VTHL (vertical takeoff, horizontal landing) spaceplane. An uncrewed, subscale spacecraft, its purpose was to test the heatshield tiles and reinforced carbon-carbon for the Buran space shuttle, then under development.[1]
Several of them were built and flown between 1982 and 1984 from the Kapustin Yar launch site at speeds of up to Mach 25, using K65-RB5 variant of Kosmos-3M launch vehicle.[2] After reentry, they were designed to parachute to an ocean splashdown for recovery by the Soviet Navy. The testing was nearly identical to that carried out by the US Air Force ASSET program in the 1960s, which tested the heatshield design for the X-20 Dyna-Soar. On 16 March 1983[3]: 207 a Royal Australian Air Force P-3 Orion reconnaissance aircraft captured the first Western images of the craft as it was recovered by a Soviet ship near the Cocos Islands.[4]
- ^ Grayzeck, Edwin.J. "NASA - National Space Science Data Center - Spacecraft - Details: Cosmos 1517". NSSDC Master Catalog. National Aeronautics & Space Administration. Archived from the original on 19 December 2022. Retrieved 16 January 2015.
- ^ "K65-RB5". Gunter's Space Page. Retrieved 14 May 2024.
- ^ Cite error: The named reference
jsd-1987was invoked but never defined (see the help page). - ^ Hodges, Jim (23 June 2011). "They're Trying to Make a Dream Come True". The Researcher News. NASA Langley Research Center. Archived from the original on 3 May 2022.