Meet NASA’s Greased Lighting (GL-10) – the 10-engine aircraft that takes off like a helicopter, but flies like an airplane. The GL-10, which is currently being developed and tested, could potentially serve as an unmanned aerial vehicle (UAV).
“We have a couple of options that this concept could be good for," Bill Fredericks, an aerospace engineer with NASA's Langley Research Center, said in a statement. "It could be used for small package delivery or vertical takeoff and landing, long endurance surveillance for agriculture, mapping and other applications.”
From left to right: David North and Bill Fredericks carry the GL-10. Source: NASA
"We built 12 prototypes, starting with simple five-pound (2.3 kilograms) foam models and then 25-pound (11.3 kilograms), highly modified fiberglass hobby airplane kits all leading up to the 55-pound (24.9 kilograms), high quality, carbon fiber GL-10 built in our model shop by expert technicians," said David North, an aerospace engineer.
The group tested its latest prototype at a military base a few hours away from NASA Langley. The aircraft is remotely piloted and boasts a 10-foot wingspan (3.05 meters) along with 10 electric motors (two on the tail and eight on the wings). It weighs approximately 62 pounds at takeoff.
Although the device had already passed a hover test, this was the first time it was able to successfully go from vertical to forward flight.
A picture of the Gl-10 prototype in hover mode. Source: NASA
"During the flight tests we successfully transitioned from hover to wing-borne flight like a conventional airplane then back to hover again,” said Fredericks. “So far we have done this on five flights. We were ecstatic. Now we're working on our second goal -- to demonstrate that this concept is four times more aerodynamically efficient in cruise than a helicopter."
The plane’s primary pilot, Zack Johns, added: “All four engines on the left wing are given the same command. The four engines on the right wing also work in concert. Then the two on the tail receive the same command."
According to the team, one of the main advantages of the GL-10 is the limited amount of noise it produces. "It's pretty quiet," said Fredericks. "The current prototype is quieter than a neighbor mowing the law with a gas-powered motor."
There is still a lot of work to be done; the group plans to work on the GL-10’s aerodynamic efficiency. But before then, the aircraft will be making an appearance at the upcoming Unmanned Vehicles Systems International 2015 conference in Atlanta.