web |url=https://www.facebook.com/SpaceX/posts/10153372146765131 |title= Grasshopper flies to its highest height to date |publisher=SpaceX |work=Social media information release |date=12 October 2013 |access-date=14 October 2013 |quote=WATCH: Grasshopper flies to its highest height to date – 744 m (2441 ft) into the Texas sky.}}</ref> This was the last scheduled test for the Grasshopper rig; next up will be low altitude tests of the Falcon 9 Reusable (F9R) development vehicle in Texas followed by high altitude testing in New Mexico. On November 23, 2015, Blue Origin's New Shepard booster rocket made the first successful vertical landing following an uncrewed suborbital test flight that reached space. On December 21, 2015, SpaceX Falcon 9 first stage made a successful landing after boosting 11 commercial satellites to low Earth orbit on Falcon 9 Flight 20. These demonstrations opened the way for substantial reductions in space flight costs. Rotorcraft Helicopter The helicopter's form of VTOL allows it to take off and land vertically, to hover, and to fly forwards, backwards, and laterally. These attributes allow helicopters to be used in congested or isolated areas where fixed-wing aircraft would usually not be able to take off or land. The capability to efficiently hover for extended periods of time is due to the helicopter's relatively long, and hence efficient rotor blades, and allows a helicopter to accomplish tasks that fixed-wing aircraft and other forms of vertical takeoff and landing aircraft could not perform at least as well until 2011. On the other hand, the long rotor blades restrict the maximum speed to about 250 miles per hour (400 km/h) of at least conventional helicopters, as retreating blade stall causes lateral instability. Autogyro Autogyros are also known as gyroplanes or gyrocopters. The rotor is unpowered and rotates freely in the airflow as the craft travels forward, so the craft needs a conventional powerplant to provide thrust. An autogyro is not intrinsically capable of VTOL: for VTO the rotor must be spun up to speed by an auxiliary drive, and vertical landing requires precise control of rotor momentum and pitch. Gyrodyne Gyrodynes are also known as compound helicopters or compound gyroplanes. A gyrodyne has the powered rotor of a helicopter with a separate forward thrust system of an autogyro. Apart from take-off and landing the rotor may be unpowered and autorotate. Designs may also include stub wings for added lift. Cyclogyro A cyclogyro or cyclocopter has a rotary wing whose axis and surfaces