The SpaceX Grasshopper has completed its latest test, called the Johnny Cash Hover Slam, in the process to create a vertical take off vertical landing reusable rocket system.
The Grasshopper project is carrying on to progress nicely for SpaceX, their latest test saw the modified Falcon 9 first stage take off and hover 24 stories or 80.1 meters (262.8 feet) in the air over the launch pad for around 34 seconds before descending to make the most precise landing of a Grasshopper test so far, landing in the center of the launch pad and providing SpaceX with good data to move forward with the project.
Watch: The Johnny Cash Hover Slam via SpaceX on Youtube
Grasshopper is the testbed for SpaceX to move forward with their plans for rapidly reusable rockets. Elon Musk has said many times that it sounds silly to buy a brand new intercontinental airplane only to scrap it after one flight, and that he sees rockets as the same. By making the rockets reusable the cost of spaceflight will be reduced dramatically as the price for fuel is only a very, very small cost compared to the cost of a rocket.
Grasshopper consists of a Falcon 9 v1.0 first stage tank,with a single Merlin 1D engine installed. The vehicle also includes a hydraulic landing support structure that is being used for the initial test flights. The vehicle ascends and descends under its own rocket power and controls itself using a closed-loop thrust vectoring system. As with the central engine on the Falcon 9 v1.1 the Grasshoppers engine is gimballed to allow thrust vectoring control. SpaceX have talked about the second Grasshopper vehicle that will be built using a new stretched first stage tank from the Falcon 9 v1.1, as well as having the landing gear installed into the body in a manner that would be used on a functional Falcon 9.
This is the fourth flight of Grasshopper to date. The first flight back in 21st September 2012 only lasted three seconds with a total flight height of 1.8 meters, known as the first hop. The second test on the 1st November 2013 lasted 8 seconds and took Grasshopper 5.4 meters off the ground before landing. The third test on 17th December 2013 took the Grasshopper up to 40 meters in the air, hovering before descending under its own rocket power and landing after a flight time of 29 seconds. This fourth test of the Grasshopper saw the vehicle fly up to 80.1 meters and hover for around 30 seconds before descending back to the launch pad and making the most accurate landing yet for the project.
SpaceX have said at a presentation that was given on the Grasshopper project that the first flight of the Falcon 9 v1.1 from Vandenberg Air Force Base will attempt to soft-land the first stage in the ocean. To do this, SpaceX intend to use a cold gas reaction control system to turn the first stage around after separation from the second stage, and use the main engines to slow the first stages decent and re-entry speed. If the first stage survives the re-entry process, flight control will attempt the landing procedure by attempting to soft-land the stage in the ocean as a proof of concept test.
Image Credit: SpaceX
Video Credit: SpaceX