Greased Lighting is a battery powered prototype aircraft that can take off like a helicopter and fly like a plane.
During its most recent test in Virginia, the remote controlled GL-10 successfully transitioned from helicopter to airplane; rotating its wings and titling its rotors. The NASA prototype is a VTOL aircraft, short for vertical takeoff and landing, which is useful in places that don't have a long runway.
VTOL aircraft already exist -- the US military;s V22 Osprey is one -- but designing such an aircraft is challenging because of the unique aerodynamics. Osprey development had significant budget overruns and delays.
NASA is working on the prototype to better understand the potential of electric propulsion across all types and sizes of aircraft
The benefit of using electric propulsion is that even with 10 motors this aircraft is quieter than a gas powered lawn mower. The plane has a 10-foot wingspan and weighs 62 pounds or 28 kilograms. The NASA team has built 12 prototypes, with the first one starting out at 5 pounds.
Piloting the aircraft is much like piloting a three engine plane. The 4 rotors on the right operate in sync, the four on the left in sync and the two on the tail in sync.
Initially Greased Lighting could be used as an unmanned aerial vehicle for surveillance, mapping or package delivery, but that will be a ways off. NASA’s next step in developing the plane is to confirm its aerodynamic efficiency.