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HELICOPTER AIR SERVICE PROGRAM   139

article. Three of these planes are currently in flight status; the fourth and fifth are on the production line at this time and are scheduled to fly in June of this year. Our major associates in the program are Hiller Aircraft Co. and Ryan Aeronautical Co. Also, major contributions are being made by Hamilton Standard and General Electric.

The XC-142 is a four-engine, turboprop, high-wing transport airplane which uses the tilt-wing deflected slipstream concept to achieve VSTOL operations.

Since this committee at this particular hearing is more interested in the commercial potential of the aircraft, my comments, with your permission, will remain in this area. First I would like to give you briefly the dimensions of the airplane. In short, the aircraft is larger than one might think. To help the committee better understand the size of the airplane, on the easel next to me is an overlay comparison of the XC-142 with the well-known DC-3. The following dimensions show the comparison.

[[3 columned table]]

|   | XC-142 | DC-3 (standard) |
|---|---|---|
| Length | 58.1 ft | 64.5 ft. |
| Height | 26.1 ft. | 16.9 ft. |
| Wing span | 67.5 ft | 95.0 ft. |
| Passenger compartment | 30.0 ft | 27.0 ft. |
| Width of fuselage | 7.5 ft | 4.5 to 6.2 ft. |
| Height of fuselage | 7.0 ft. | 5.75 to 6.3 ft.|
| Cruise speed on 2 engines | 300 m.p.h. | 160 m.p.h. |
| Maximum speed on 2 engines | 350 m.p.h. | 220 m.p.h. |
| Maximum speed on 4 engines | 430 m.p.h. |   |
| Main propeller, diameter | 15.6 ft | 11.5 ft. |
| Tail propeller, diameter | 8.0 ft.|   |
| Conventional takeoff gross weight with 7,500-lb. payload |   |26,000 lbs. |
| Vertical takeoff design gross weight at t/w ratio of 1.15 with 8,000-lb. payload | 37,474 lbs |  
| Short takeoff gross weight with 12,000-lb. payload | Up to 45,000 lbs |   |

This aircraft can be operated nonstop on a ferry mission up to 3,800 miles which gives it the ability to move quickly to any area in the world.

The design specifications of the XC-142 call for the aircraft to rise vertically to 8,000 feet at zero forward speed. Obviously then, the airplane can hover at any point in between a few inches from the ground up to 6,000 feet. In order not to mislead the committee, I would like to say this ability has not yet been demonstrated, nor will it be in the present configuration of the aircraft for two reasons; first, an overweight condition and, second, a thrust deficiency, both of which we are confident can be corrected.

The XC-142 is also designed to hover in a 25-knot tailwind.

In the STOL configuration, that of supershort takeoff and landing, the airplane can operate from a "landing court" 200 feet square and clear a 50-foot obstacle with maximum gross weight of over 41,000 pounds. The range in this configuration with a 4-ton payload is about 950 miles.

There is attached to my statement a table which gives several specific examples of short takeoff and vertical takeoff range, payload combinations for which the XC-142 was designed.

The best evidence of how well the XC-142 is performing in the early stage of the flight test program is to now show, for the benefit of the committee, a 12-mnute film of its VSTOL capabilities. (Shows film.)

I would like to point out to the committee that in the normal cruise configuration the airplane operates on only two engines and has a cruising speed of about 300 miles per hour. Maximum speed with all 4 engines is 430 m.p.h. A comparatively new innovation in the XC-142 is that all four engines are inter-connected by a cross-shafting arrangement which permits all four propellers to rotate regardless of the number of engines producing power. You will be interested to know also that with any three engines of the four shut down, the remaining engine alone will still drive all four propellers and maintain the airplane in level flight at a speed of 200 miles an hour--much faster than a DC-3 can in level flight at a speed of 200 miles an hour--much faster than a DC-3 can cruise.

Gentlemen, as you have seen from the movie, the XC-142 is designed to fly like a conventional fixed-wing airplane in the cruise configuration. Along with its ability to also hover then the XC-142 literally combines the hovering and low speed characteristics of the helicopter with the high efficiency cruise speed of a modern turboprop transport.