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 again.

   

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 assistance.

   

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 Administration.

Source: Office of Naval Research