DARPA Funding Gyrodyne Heliplane R&D
Small business qualifier Groen Brothers Aviation (GBA) in Salt Lake City, UT are well known for their advocacy of and experience with gyrodyne technology. Gyrodynes use tip-acceleration to spin rotors for vertical or USTOL (Ultra-Short Take Off and Landing) takeoff and initial flight, then switch to conventional wings and propellers and place the heliblades in autorotation. Hovering capability is limited with gyrodyne designs, but vertical landing is achieved through this autorotation and works even without power.
GBA participated in but lost a bid for a Joint Heavy Lift concept design contract; fortunately for GBA, they have another DARPA “heliplane” contract. They were recently awarded a $3 million increment of their $6.4 Phase One award, which provides for preliminary design and key technology demonstrations.
Groen Bros. has now issued additional informaton with regard to this contract and its team, including a somewhat surprising focus for their efforts.
The aircraft will be “a proof of concept high speed, long range, vertical takeoff and landing (VTOL) aircraft designed for use in Combat Search and Rescue (CSAR) roles.”
GBA claims that use of powered rotors for short-term hovering/takeoff and main engines for forward thrust eliminates the need for much of the cost, weight, and complexity found in helicopters, while permitting much higher forward speeds and creating additional safety from the blades’ natural autorotation in forward flight.
This could make their vehicles attractive for the US Air Force CSAR-X/PRV contract. The Bell-Boeing team recently withdrew their PRV-22 Osprey tilt-rotor from that competition, citing budgetary restrictions that did not suit their ($80-110 million) aircraft. Gyrodyne technology aims to break many of the same performance barriers as aircraft like the V-22, but may be able to do so at a cheaper cost.
Unfortunately, timing would appear to be working against GBA for the CSAR-X/PRV competition. Phase One of their potentially multi-year, $40 million, 4-phase DARPA award begins with a 15-month, $6.4 million award to develop the preliminary design and perform key technology demonstrations. Meanwhile, the USAF is looking at competition in the FY 2006 timeframe in order to have the PRV contract awarded by the end of 2006 if possible.
GBA’s team includes:
- The Georgia Institute of Technology (Georgia Tech), whose Center of Excellence in Rotorcraft Technology has done extensive research on the gyrodyne concept.
- Adam Aircraft Industries, known for its innovative use of modern composite materials and rapid prototyping processes that has allowed Adam to bring to market two new high-performance aircraft: the six passenger “center-line-twin” A500 and the A700 personal jet
- Williams International, has developed more than 40 different small gas turbine engine systems for both military and commercial air vehicles, including the Adam A700 and other modern business jets.
- And a team of aerospace consultants.
GBA’s work on the above-mentioned DARPA contract will be performed in Salt Lake City, UT (70%); Atlanta, GA (20%); Walled Lake, MI (5%); and Englewood, CO (5%); and will be complete in January 2007. Funds will expire at the end of this fiscal year. DARPA issued a solicitation in Federal Business Opportunities on February 16, 2005, and multiple proposals were received. The Defense Advanced Research Projects Agency is the contracting activity (HR0011-06-9-0002).
DID will continue to follow such technologies with interest, given their potential to offer revolutionary performance gains without sky-high costs.
Sidebar: GBA’s Joint Heavy Lift Bid
It’s worth highlighting GBA’s JHL bid, not only because of its potential long-term promise for US transport aircraft technology, but also because it can provide a window on the small number of companies and organizations connected to this technology space.
For their unsuccessful JHL bid, Groen Brothers Aviation was part of a team that included Georgia Tech, Shafer Corp. which brough experience developing many of the US Army’s premier rotorcraft platforms, and Dancila LLC for its rotor tip-jet performance enhancements. Lockheed and Rolls-Royce (whose engines power GBA’s Hawk 4) played roles as supporting firms, willing to offer their C-130 and engine technologies should the GBA team win.
As GBA described their JHL concept:
“GBA is offering a gyroplane solution to meet the US Army’s need for a vertical take-off and landing heavy lift transport. GBA’s concept is in response to a Department of Defense study contract announced last year to examine different concepts for meeting the Army’s need for an Advanced Maneuver Transport (AMT). … GBA’s proposal would modify a Lockheed Martin C-130. It would be relatively easy and inexpensive to transform the C-130 cargo transport into a heavy lift gyrodyne by equipping it with a GBA designed rotor system incorporating rotor-mounted tip-jets.
The GBA GyroLifter could rapidly be made available as an interim fast, long range VTOL transport capable of carrying large loads of troops and equipment long distances without the need for runways at either end of the mission. … A variant of this design could be the critical multi-role aircraft necessary for an effective seabasing strategy for the military service. Other military variants of this gyrodyne technology can also be developed, including: large two man gunships; small, light observation and courier aircraft; and VTOL UAVs.”
GBA has already tested this concept by modifying a Cessna Skymaster airplane and turning it into a gyrodyne. This conversion, using minimal assets, took less than one year from first conception to first flight.
The JHL competition concept design award winners included compound helicopters, coaxial rotors with advancing blade concept, tilt-rotor, and optimum speed rotor technologies. DID coverewd each of these new technologies in turn. Now GBA’s ability to pursue its Heliplane C-130 option adds a new technology to the potential mix, one whose relative simplicity and safety in loss of power situations could make it a strong contender in the competitions for future medium transport aircraft.
Mu-1 can be thought of as the rotary equivalent of Mach 1, with similar buffeting challenges in the lead-up and consequent limits on safe aircraft speeds. Carter Aviation believes that a ratio of Mu-5 may be possible with their CarterCopter technology, where the aircraft is traveling at speeds up to 500 mph and the tip speed of the advancing rotor blade remains under mach 0.9.
- Popular Mechanics (June 15/04) – Giant Gyros. Covers both GBA and Carter Aviation’s plans for medium-lift gyroplanes/ heliplanes. Good illustrations, including the one with capacity comparisons to current heavy-lift rotorcraft.