Boeing X-37B, the Orbital Test Vehicle (X-37B OTV), is an American unmanned robotic vertical-takeoff (with using of rocket), horizontal-landing spaceplane.
This spaceplane is designed to operate at altitudes of 200-750 km, it is able to quickly change the orbits, make evolutions, also it can perform the reconnaissance missions and deliver a small cargo to (from) space.
General characteristics :  
|Loaded weight||4990 kg|
|Payload weight||900 kg|
|Powerplant||1 x Aerojet storable liquid propellant rocket engine (hydrazine)|
|Power||Gallium arsenide solar cells with lithium-ion batteries|
|Payload bay||2.1 x 1.2 m|
|Orbital speed||28044 km/h|
The X-37 began as a NASA project in 1999, before being transferred to the U.S. Department of Defense in 2004. It conducted its first flight as a drop test on 7 April 2006, at Edwards Air Force Base, California.
The spaceplane’s first orbital mission (USA-212) was launched on 22 April 2010 using an Atlas V rocket. X-37 successful return to Earth on 3 December 2010. A second X-37 was launched on 5 March 2011 (USA-226 mission) and returned to Earth on 16 June 2012.
1. USA-226. – Mode of access: http://en.wikipedia.org/wiki/USA-226.
2. File:Boeing X37B OTV2 enclosed in fairing.jpg. – Mode of access: http://en.wikipedia.org/wiki/File:Boeing_X37B_OTV2_enclosed_in_fairing.jpg.
3. Boeing X-37. – Mode of access: http://en.wikipedia.org/wiki/Boeing_X-37.
4. File:X-37B OTV-2 Landing (June 2012).ogv. – Mode of access: http://en.wikipedia.org/wiki/File:X-37B_OTV-2_Landing_%28June_2012%29.ogv.
5. NASA – NSSDC – Spacecraft – Details // OTV 1. – Mode of access: http://nssdc.gsfc.nasa.gov/nmc/spacecraftDisplay.do?id=2010-015A.
6. NASA – NSSDC – Spacecraft – Details // OTV 2. – Mode of access: http://nssdc.gsfc.nasa.gov/nmc/spacecraftDisplay.do?id=2011-010A.
7. Boeing X-37. – Mode of access: http://uk.wikipedia.org/wiki/Boeing_X-37.
8. Boeing X-37. – Mode of access: http://ru.wikipedia.org/wiki/Boeing_X-37.
9. X-37B Orbital Test Vehicle lands at Vandenberg. – Mode of access: http://www.vandenberg.af.mil/news/story.asp?id=123306242.
1 As a work of the U.S. federal government, the image is in the public domain.