Get Your Rotor Runnin': ONR-sponsored Flexrotor Program Takes off for Next Phase
ARLINGTON, Va.-Part helicopter, part airplane, the Office of Naval
Research (ONR)-sponsored Flexrotor vertical takeoff and landing
unmanned aerial vehicle (UAV) enters the next development phase April
30 in delivering improved maritime surveillance capability.
The contract awarded today is for the flight controls component.
During this phase, Aerovel Corp. will advance Flexrotor's capability
with an upgraded propulsion system to transition from vertical to
cruising flight and to land in crosswinds and high winds. The
aircraft's first major milestone was in August 2011, when it
successfully transitioned from horizontal to vertical flight and back
The small UAV features a unique design. It has an oversized propeller
with helicopter-like controls for vertical takeoff and landing and the
wings of a conventional aircraft. The goal is that it will take off
vertically, cruise efficiently horizontally and then land vertically.
"With Flexrotor, the two biggest benefits to Sailors and Marines would
be the ability to do extended maritime surveillance from a ship, and
to do so with a small footprint," said John Kinzer, ONR program
officer for Air Vehicle Technology.
Taking up less than one-half the space needed by other UAVs, Flexrotor
would give Sailors compact, ship-launched, eye-in-the-sky capability.
Additionally, it could stay airborne for a longer period of time.
Thus, Flexrotor could help meet the Navy's perpetual need for more and
better maritime surveillance.
A vertical takeoff/landing craft requires a complex propulsion and
flight control system. The propeller needs to be big enough to provide
sufficient lift to take off vertically, yet small enough to be
efficient while in horizontal flight. The flight controls must provide
powerful and precise control in vertical takeoffs and landings and
efficient, low-drag control in forward flight. Perfecting both the
rotor and other flight capabilities requires a constant balancing act
among power, efficiency and weight, and this is what Tadd McGeer,
Flexrotor's inventor, is working out during phase II.
Since test flights to date have occurred with light winds, Aerovel
will begin testing in windy conditions, gradually increasing the
aircraft's operating envelope.
Another aspect of the program, sponsored by the Naval Air Warfare
Center Aircraft Division, is to develop an autonomous servicing
capability. Aerovel is creating an Automatic Servicing Platform that
would serve as launch and landing pad, as well as maintenance bay.
This could be useful when deploying the Flexrotor to remote areas, as
the aircraft could use this all-in-one hub without needing human
The platform could be beneficial for a special operations application
of remotely siting a UAV. "[The special ops personnel] like the idea
of not exposing where they are when they need to launch and recover
one," Kinzer said. "They could put it on a mountaintop somewhere and
just leave it to do surveillance." There are also potential
applications to Arctic surveillance and weather reporting for the Navy
and other organizations, such as National Oceanic and Atmospheric