Customer:California Microwave, Inc. Type: proof-of-concept optionally-piloted reconnaissance aircraft Program: CM-44 (proprietary) Powerplant: 1 x 282 hp Lycoming TIO-360-CSignificant date: 1987 The Rutan 'Long-EZ' family has an enduring history of UAV research. As early as 1984, a couple of Long-EZs were built at Fort Lewis under codename Monkey Green as Threat Support Activity (TSA) covert ops aircraft. Their purpose was to simulate cruise missiles and UAVs. In 1986, Aeromet Inc. of Tulsa, Oklahoma, converted several Cozy Mark IVs into a remotely controlled version for use with the US military, the Autonomous Unmanned Reconnaissance Aircraft', or AURA, considered by many as the very first modern UAV. That same year, the Government Electronics Division (GED) of California Microwave developed a multi-purpose conversion of the RAF Long-EZ into an Unmanned Airborne Vehicle (UAV) designated the CM-30. Three Long-EZ homebuilts were purchased from private pilots and modified to drone configuration. Neither Rutan nor Scaled Composites had anything to do with this early project. Two primary pilots, Bob Cunningham, former Air Force SR-71 pilot, and Tony Hoskins, a civilian pilot and aero engineer, test flew the CM-30 prototype. Cunningham was the energy of this project and bought his own Long-EZ. Hoskins was slow and steady, but both were good pilots. The former devised methods and systems to launch missiles and bombs from the CM-30. The CM-30's had different variants/missions, thus the extra numbering as in the quoted CM-30-3. The company did get some interest from a government agency which helped develop the CM-30 platforms. Executives and program managers at SCI/GDE decided they should have a platform that could carry more equipment and heavier weights. The CM-44 was initially designed by CMI/GED as an enlarged Long-EZ built from stealth materials, a Lycoming 360 turbo-engine and a large rear compartment which could accommodate two passengers or mission equipment (sensors for ELINT, photo, etc.). Though the design was proprietary to California Microwave, Inc., the CM-44 was built by a small division of Scaled Composites called Composites Prototypes, which occupied Building 13 on the Mojave flight line (the one that RAF used to be in), under the supervision of CMI's GDE team. Designated by Scaled as their Model 144, this was the very first aircraft constructed by Scaled at Composites Prototypes. Like the CM-30, the CM-44 was a private venture from CMI, who financed the whole program. The prototype (N935SC) made the first flight (which was the acceptance flight) on February 27, 1987 with Mike Melvill at the controls. California Microwave accepted the CM-44 and flew in Lincoln Airfield between Sacramento and Beale Air Force Base, California (the home of the SR-71). The UAV had a 30 foot-plus wingspan and used a 210 hp, turbo-charged Lycoming TIO-360-C engine developing 210.3 kilos of thrust. The CM-44 proved to be a great aircraft. It operated and flew as designed. It had good range, versatile mission capability and a solid engine. Developmental flight testing ensued, and both the Army and Navy evaluated the CM-44, the former receiving two examples. In the fall of 1987, CMI approached aircraft designer Martin Hollmann and asked him to fix a problem on their CM-44. At 95 knots, the aircraft would yaw 45 degrees opposite to the direction of the turn, which was very uncomfortable to the pilot. No one knew what the problem was but Hollmann felt he could solve it with the help of some friends, and agreed to help. Tests on a lattice vortex model of the existing CM-44 showed that, during a turn, the downward moving winglet was stalling causing the upward moving winglet to push the nose in the opposite direction of the turn. John Roncz therefore designed a new canard airfoil. Hollmann sent CMI a list of the items that needed corrections on the CM-44, prior to getting a contract to design and build the CM-44A. These items included:· The wing wass only twisted 2.5 degrees and should be washed out 6 to 7 degrees; the winglet was aligned with the wing leading edge so that the pressure peaks coincided, and therefore The winglet should be moved aft as far as possible to keep the pressure peaks from aligning; the airfoil of the wing tip and winglet should be laminar flow, high lift airfoils which would not stall at high angles of attack, while the present CM-44 airfoils had poor stall characteristics; the wing taper ratio on the CM-44 was too high, and the tip chord too low in comparison to the root chord; finally, the angle of incidence of the winglets must also be properly selected. Using the lattice vortex program, the aircraft was resized, new wings, winglets and a canard were designed and built, and the aircraft, now called the CM-44A, was test flown. As CMI reported "We have a winner." Not only was the yaw problem solved but the take off distance was shortened to about half. The wing taper ratio had been the culprit and reducing it kept the wing tip and the winglet from stalling. The CM-44A could now use a larger canard area which allowed it to fly slower. The airframe was made of foam and fiberglass, and propulsion was made by a three-bladed composite propeller. Along with the top-mounted engine inlets and flap fuselage surfaces, the propeller gave the CM-44 stealthy characteristics. A further variant was developed as the CM-44B, a two-seater version. The CM-44 was eventually certified on February 18, 1997, ten years after its first flight, but the program came to a halt shortly after, when most of the project's assets were destroyed at the direction of the CMI President, who was concerned about liability. For some obscure reason, the prototype N935SC was not destroyed; it was apparently leased for a while to JD Enterprises (a company whose business is Specialty Cleaning Polishing) and then resurfaced around 2006 in the hands of a private owner. Recently it was even put for sale on the internet for a price tag of $150,000. A final development called the CM-46 was the result of a Hollmann redesign, and contrary to the CM-44, was government funded. Developed from a navigator's, not a pilot's point of view, the CM-46 was ugly, couldn't fly properly and never went operational. No picture of this has ever been released. The 'Long-EZ' has always been an ideal candidate for an OPV conversion. A more recent version of the Long-EZ for the military was the VZ-10 threat simulator for the Army's OPFOR, while the Velocity XL RG, a Long-EZ derivative, was evaluated as the VZ-11. Population: 1
prototype
CM-44 (N935SC, c/n 0001) Crew/passengers: 1, 2 or none Main sources:
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