SpaceX Grasshopper tests sensor system, reaches record altitude of over 1,000 feet
By Brian Dodson
July 8, 2013
Back in June, SpaceX's Grasshopper reusable VTOL rocket was flown to an altitude of 325 meters (1,066 feet) before landing on its original launch pad. The video of the flight (taken by a hexacopter drone hovering at 325 meters) has now been made available. The purpose of the flight was to test Grasshopper's full navigation sensor suite with the F9-R closed loop control flight algorithms to improve the precision of its landings. Grasshopper is designed to develop and test the technologies needed to return a reusable rocket from space missions. (There is no word on whether the cowboy mannequin was carried along by Grasshopper on this flight.)
Over the long run, SpaceX is depending on its ability to develop a reusable rocket launching system to carry payloads to and from orbit. Their Grasshopper VTOL rocket is an important part of the intended system, which will soon be extended by controlling the descent of Falcon 9 booster stages from altitude and the introduction of a new version (1.1) of the Grasshopper intended for supersonic flights from New Mexico's Spaceport America.
Grasshopper v1.0 is clearly a test vehicle, composed of Falcon 9 first stage tanks that occupy 85 ft (26 m) of the 106 ft (32.3 m) total height of the v1.0, a Merlin 1-D engine, four landing legs, a support structure, and a state-of-the-art guidance and navigation system. The Merlin 1-D runs on liquid oxygen and RP-1, a highly refined version of kerosene, and can provide 150,000 pounds of thrust. While the tanks are those of a Falcon 9, a Falcon 9 first stage boasts nine Merlin 1-D engines. A single Merlin 1-D could not budge a fully fueled Falcon 9 first stage, thus limiting the amount of fuel to about 40 tons. Still, this would allow the Grasshopper about 3 minutes of full thrust. On this flight, the Grasshopper was powered for about 68 seconds, for an average speed of about 10 m/s (about 22 mph.)
Test flying of the SpaceX Grasshopper v1.0 will continue at SpaceX's private flight facility, and is intended to reach to altitudes up to 11,500 feet (3.5 km). The Grasshopper v1.1 is currently being built, and should be ready to begin supersonic testing in New Mexico in 2014.
You can see SpaceX's hexacopter-captured footage of the Grasshopper launch below.