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140 HELICOPTER AIR SERVICE PROGRAM We are extremely proud of the engineering breakthroughs we have made in stability and control on this aircraft for vertical lift and in transition from a vertical to horizontal flight configuration. For example, from a practical standpoint and following a very brief instruction period, each of the three military pilots currently flying the XC-142 was able on his first attempt to control the aircraft extremely well in the hover mode——attesting to the breakthrough in controllability. First conventional flight of the XC-142 was made on September 29, 1964. First hover flight was successfully completed on December 29, 1964. And, the first flight conversion from hover attitude to conventional mode was made on January 11, 1965. Outstanding features of this airplane are- 1. Tilt wing fully immersed in propeller slipstream which with adequate propeller thrust makes the wing stallproof. 2. Propellers, gearbox cross-shafted to each other. 3. Exceptional stability and control during hover. 4. Excellent super STOL capability. It is emphasized that interconnecting shafting used primarily for safety purposes and, unlike the helicopters, the shafting carries appreciable loads only when one or more engines are turned off. When all four engines operate, the shafting systems is essentially idling. The tail rotor system operates only during the hover mode. The overweight situation which I mentioned is a result of a decision early in the design stages to relax weight-control efforts in the interest of reducing overall costs. This was agreed to by the Air Force and the company because we felt it would not significantly impair the ability of the airplane to satisfy the basic objectives of the operational evaluation testing in the field. The XC-142 is powered by four General Electric T-64 engines and is an outstanding powerplant in our opinion. This engine weighs only 713 pounds and produces more the 3,000 horsepower, which is approximately equal to the power output of 15 modern high-powered automobile engines. The engine, although putting out 15 times the horsepower of an automobile engine, weighs only twice as much as an automobile engine. In vertical lift, these four engines, which so far have exceeded expectations by almost 10 percent, put out approximately 48,000 pounds of thrust at full torque. In some respects the flight controls are unique in that, whenever the aircraft is in the hover mode, the tail propeller provides pitch control, the ailerons give directional control, and the main propellers provide roll control. In conventional flight, control is accomplished in the normal manner of all fixed-wing aircraft with a standard assortment of ailerons, elevators, and rudder. During conversion from vertical flight to horizontal and vice versa, the controls are mechanically phased from one mode to another in such a manner that pilots inputs for controllability do not change. As regards the commercial adaptability of the XC-142, LTV is now analyzing this from a practical standpoint with emphasis on the potential profitability and economics of the aircraft to scheduled operation. A study is underway at this time to cost the airplane over specific routes using the known operating costs of airlines currently providing service over these routes. This study is not complete at this time, but we will be happy to supply the chairman and members of the committee copies of the study when completed in a few months. Among other things, I can say with certainty that the commercial unit flyaway cost and maintenance costs will depend to a large degree on the future of the airplane in the military inventory. Additionally, at this point in time, it is difficult to evaluate what is required to certificate the airplane for commercial use because there are no FAA standards established for this type of machine. We have already had several exploratory conversations with some of the airplane operators regarding the potential of this aircraft in satisfying some of the future transportation requirements they foresee. I must say that we are pleasantly surprised with the high degree of interest expressed by these knowledgeable people who are fighting the public air transportation problem every day. From our meetings with the commercial operators, we can see where, with some modification, the XC-142 in its commercial version can be adapted to carry somewhere between 40 and 50 seated passengers depending on the degree of comfort required. At the present time, we don't know it this capacity is optimum; but it must be carefully evaluated in determining the ultimate economics of the airplane. It may be necessary in the commercial configuration
