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Wing data: area (including portions covered by engine nacelles and not including portion covered by fuselage) 75 square feet; span, 26 feet; dihedral of leading edge, 7o.
Tail group data: area, horizontal tail surfaces, 22.7 square feet; area, vertical tail surfaces, 25.0 square feet.
Power plant: 2 Lycoming, GSO-375 horsepower, 750 horsepower; power loading, 10.1 pounds per horsepower; (power loading of Model 7B, 12.5 pounds per horsepower).
Body dimensions: Length 22.5 feet; height to top of rotor, 14.66 feet; landing gear tread, 12.83 feet; cabin size: length, 10 feet; height at aisle, 6 feet; width, 5.5 feet.
Weights: design gross, 7,600 pounds; empty (completely equipped with crew accommodations but without passenger or cargo accommodations), 4,646 pounds; useful load (including passenger or cargo accommodations), 2,954 pounds.
Performance: hovering ceiling out of ground effect, 8,800 feet; hovering ceiling in ground effect, 13,000 feet; high speed at 3,700 feet with 750' horsepower, 162 miles per hour; cruising performance at 5,000 feet with 608 horsepower, 150 miles per hour; economy cruise at 5,000 feet with 468 horsepower, 128 miles per hour; rate of climb (first minute), 937 feet per minute; fuel consumption-economy, 0.292 gallon per ton-mile; fuel consumption-cruising, 0.370 gallon per ton-mile; normal range, 275 to 345 miles; maximum range (normal fuel capacity-no extra fuel tanks), 1,100 miles; wing lift at 150 miles per hour and 5,000 feet, 2,500 pounds; rotor lift at 150 miles per hour and 5,000 feet, 5,100 pounds.
Pay load: number of crew, 2; number of passengers, 10; cargo (no passengers), 2,000 pounds.
Price: Delivered complete with engines and instruments, $125,000.
The Helidyne, according to its manufacturer, will surpass the station-to-station traveling times of any other type of surface or air vehicle or combination of both for short- or medium-haul transportation. Its cruising speed will surpass that of the ordinary helicopter or any surface transportation, and its ability to fly out of urban heliports will cut out the airport-to-city run and thus cut down the total traveling time on short or medium flights. An added utility factor is the fuselage design, which insures the operator a wide choice of cargo, the cargo or passenger space being completely unobstructed and accessible from the front or rear.
Safety factors are many. In addition to the twin-engine installation, allowing for flight on only one engine, the rotor blades are always in an autorotative attitude, since they operate at minimum blade-pitch angles, and in a substantially level plane during forward flight. Furthermore, according to the company, a lower rate of descent in autorotation is provided by co-axial rotors. Provisions for declutching of propellers will prevent accidents in landing, taking off, or loading. An added safety feature is that provision has been made for complete engine preheating and deicing of all lifting and control surfaces. Furthermore, all movable rotating controls are enclosed to prevent ice formation. The company expects that the built-in long life expectancy of vital parts will guarantee greater safety. Finally, the Helidyne's smaller over-all dimensions when compared with other craft of comparable capacities will afford a greater margin of safety when operating in tight places.
Passengers should appreciate the fact that the engines are installed outside the fuselage, a factor that will cut down the vibration and noise level to about that of an airplane. The fact that this craft flies level at all times should assure additional passenger and pilot comfort.
The designers further state that the jet ejection engine cooling will eliminate the necessity for cooling fans and their replacement requirements. Clutches have been eliminated by the use of manually operated band brake mechanisms.
Because passengers and cargo may be loaded about the center of gravity, no ballast is required when flying with less than full payload. No adaptations of the plane are required for landings on water or snow because the water-tight fuselage and wings can double as sponsons. A two-speed engine transmission is provided for maximum lift and maximum forward speed. Although by no means a small craft, the fore and aft alinement of the rotors and the short wing span will permit storage in fairly small spaces.
Despite its new design, operation of the craft is comparatively simple. The conventional twin-engine arrangement will be familiar to experienced airplane pilots. Transition from helicopter to airplane flight is accomplished by the engagement of the propellers through manually operated band-brake mechanisms. When the propellers are disengaged, the aircraft converts to normal helicopter operation. The coaxial rotors simplify helicopter flying by eliminating the torque-reaction control requirement. The same rudder pedals are used for directional control during both helicopter and airplane flight operations.
By comparison with an equivalent airplane, the Helidyne has smaller wings and tail surfaces and a shorter fuselage because of the distribution of lift and control forces between its airplane and helicopter components. Because its range requirements and landing load factors are lower than those of an airplane, its structural weight is less.
In comparison with equivalent helicopters, it has a lighter fuselage because of the elimination of torque-reaction loads. The fuselage structure is greatly simplified by the elimination of submerged power plant installations. The positive band brake engagement eliminates the bulk of centrifugal clutches. The semimonocoque construction of the all-metal blades results in lighter, longer wearing, low-cost blades.
Gyrodyne engineers explain the higher performance of this craft by pointing to the reduction of blade pitch requirements in forward flight, which reduces blade flapping and vibration. Because of the low blade pitch, there is no sudden loss of revolutions per minute in the event of engine failure, since the craft is virtually in an autorotating attitude at all times. Furthermore, the level flight attitude eliminates fuselage negative lift. Objectional lateral azimuth forces, both steady and vibratory, are eliminated by the cancellation of the side forces on each rotor. The advantage of the rigidly interconnected type of rotor is that it reduces blade structural deflection, vibration due to Coriolis effects and control feed-back forces. Furthermore, this type of rotor eliminates the possibility of “ground resonance.” The reduction of blade flapping and the availability of aerodynamic damping from the propellers considerably increases stability in forward flight. Automatic locks prevent rotor blade flapping at low rotor speeds and eliminate the danger of damage due to unrestricted flapping during landing warm-up and idling.
The contra-rotating rotors neutralize torque reaction on the feselage, thus eliminating inertia and torque effects, or “ground looping” during quick starts or stops of the rotors. Because of the high peripheral velocity of the blades, the greater kinetic energy of the coaxial rotor system permits vertical descent at a much slower rate during power-off landings.
The easy accessibility of the engines, in outboard nacelles above the wing, insures ease of maintenance, service and replacement. Furthermore, all gear boxes and drive shafts are completely accessible from outside the ship. The radio sets, housed in the rotor gear box fairing, are accessible either from the inside or the outside for easy removal or maintenance. The bag-type tanks are also easily removed or replaced. Hardware and furnishings, mainly of automotive types, can be maintained or replaced at low cost.
According to the manufacturer, the high cruising speed of the Helidyne offers several advantages; reduced operating cost per ton-mile, increased range or payload in .comparison with conventional helicopters, greater number of trips in a given length of time, servicing of more remote areas, and attraction of more passengers because of lower fares or trip times.
Other attractive features of the craft are its amphibious nature, which allows it to serve more areas, its deicing provisions, which allow it to maintain strict flying schedules, and its level flying attitude, which will permit the use of conventional blind flying instruments. The readily accessible cargo space, combined with the crane arrangement, will cut loading and handling costs to a minimum.
Many features of the craft were planned with an eye to reducing costs. The installation of the engines in outboard wing nacelles eliminates special engine modifications and expensive installation costs. Twin-engine installation, although heavier, reduces the over-all power plant cost for a given horsepower when extras are considered. Transmission assemblies are more economical for contra-rotating rotors due to power division and to the elimination of planetary systems. Special soundproofing are eliminated by removing the power plants from the feselage. Semimonocoque all-metal blades are adaptable to mass production methods and will allow single blade replacements. The simplified structure of the feselage not only increases payload by reducing structural weight but also reduces cost.
The CHAIRMAN. Mr. Charles Parker, executive director, National Aviation Trade Association, of Washington, D. C.
STATEMENT OF CHARLES PARKER, EXECUTIVE DIRECTOR,
NATIONAL AVIATION TRADE ASSOCIATION
Mr. PARKER. Gentlemen, I submitted a statement last week in writing. I have been asked by the NASAO if I would be so kind as to read the letter that the president of the Aeronca Aircraft Corp. submitted, but which he was unable to be present to read.
This is written by Mr. John A. Lawler. The Aeronca Aircraft Corp. is one of the light plane and personal plane manufacturers.
The letter is dated May 9, 1950: Honorable CHAIRMAN AND MEMBERS OF THE SENATE COMMITTEE ON INTERSTATE
AND FOREIGN COMMERCE. I deeply appreciate this opportunity to present to you my views with respect to Senate bill 2984, now under your consideration. I am heartily in favor of the enactment of this legislation, substantially in its present form.
Aeronca Aircraft Corp. has been engaged in the manufacture and sale of personal aircraft for over 20 years. Our company was the pioneer in this field. I have been its president since July 1948 and was previously connected for a number of years with Curtiss-Wright Corp.
My experience in the aeronautical field accordingly covers not only the problems of a large manufacturer of military and commercial transport aircraft, but also the smaller two- and four-place airplane manufacturers, whose product is used by businessmen, commercial operators, student instructors and the field forces of the United States Army for the observation of artillery fire, reconnaissance, and general liaison purposes.
The importance to our country of maintaining a healthy light airplane industry and a large number of certificated civilian pilots cannot be overestimated. This was recognized by the Congress prior to the last war when the civilian pilot training program was instituted. It was because of the assistance of this program that the AAF were able to draw upon a large group of trained civilian instructors who readily could be converted into military instructors. Large numbers of civilian pilots who had received their preliminary training in the program were absorbed into the Army Air Forces.
Early in 1942 the Army Ground Forces found that existing types of light aircraft manufactured by ourselves and similar companies, could be used effectively in combat for the observation of field artillery fire. The required instructor personnel were readily available from the ranks of civilian commercial instructors and the aircraft were as readily obtained from off the civilian assembly lines. Thousands of such planes were used by the Army Ground Forces in combat.
Light airplanes have become an integral part of the organization and equipment of the Field Artillery, Infantry, Combat Engineers, and Armored Forces of our Field Forces today.
Unfortunately, the present market for smaller aircraft for industrial and personal use, adaptable for military service, is severely curtailed. Likewise the Army Field Forces funds for procurement of light aircraft has been curtailed. In 1946, with a pent-up demand to be filled and trainers required for flight training under the GI bill my company sold and delivered almost 8,000 such airplanes,
The entire light airplane industry in that year sold and delivered approximately 33,000. In 1949 my company sold and delivered 312 such airplanes and the entire industry sold and delivered only 3,358-one-tenth of the 1946 sales.
A few reasons for the presently restricted market are the comparative lack of commercial utility of airplanes of this type. Of all the cities and villages of this country to which a prospective owner may want to fly, proportionately only a few have established airports and the majority are not in close proximity to the center of the city. The small airplane is unable to overcome the hazards of weather through which large transport types, equipped with complicated instruments, radio equipment, deicing equipment, and two or more engines can fly with ease and safety.
I am confident that my company and other light aircraft companies have the engineering brains and manufacturing know-how to develop new types of personal aircraft which could take off and land in much smaller areas. This would make accessible to air transportation many localities now inaccessible and greatly reduce the cost of future airport construction. Development of light aircraft with greater load carrying capacity would enable safety features to be made available, such as larger gasoline "capacity, greater instrumentation, the ability to carry more and better radio and navigation equipment, and so on.
However, such developmental work is extremely expensive. Only a few of the present light airplane manufacturers have the funds to risk in the development of new and modern improvements in airframe, instrumentation, navigation, and so forth. Even they are content to make minor changes and slow, gradual improvements, rather than to embark on any serious program looking toward construction of anything really new and advanced, for fear that the end product might not be as successful as hoped, or even if successful, might be accepted with hesitation by the flying public.
In either event, severe and crippling losses might put them wholly out of business. Yet, it is only through such aggressive development that a large industrial and personal aircraft industry can be built up. Such an industry, in the event of emergency, would provide a grant reservoir of manufacturing facilities, and trained pilot and mechanic personnel for use by the defense forces, at the minimum in cost to the Government.
In the last 2 or 3 years, certain individual engineers and designers, not presently employed in the active manufacture of light aircraft, have designed and in a num. ber of cases produced and flew, new airplanes showing tremendous promise along the lines I mentioned above. In almost every case their funds were exhausted before they could complete the necessary service testing and long and expensive process of CAA certification required before such airplanes could be put on the market.
Because of the present limited commercial market it has become almost impossible to obtain public or private financing for development and experimentation, except by concerns already well established and financially sound, and even they can only do so with difficulty. Such concerns, as mentioned above, are content to make minor improvements each year rather than to risk their working capital in an expensive research and development program without a complete guarantee of its recovery. The circle is vicious. Without a substantially increased commercial market, no company can afford to spend large sums for research and development of personal aircraft with a wide appeal. Without such aircraft with wide appeal, the market will continue to remain restricted.
In my opinion, the bill under consideration would break this deadlock. With the funds provided by this bill, carefully administered with imagination, coupled with sound common sense and an understanding of aeronautical problems, there is no reason why there should not be developed greatly improved types of aircraft and related equipment. The availability of these will greatly widen the usefulness of industrial and personal aircraft, adaptable to military use, and the market will be greatly enlarged. Ultimately, through the provisions of this bill, a large portion of the cost to the Government of this development should be recaptured.
I have one suggestion to make with regard to the bill. Subsection (c) of section 5 apparently provides that, under proper safeguards, any inventions made by subcontractors doing development work would be made available to the public. I believe that in addition, provision should be made that, on fair and equitable terms, the drawings, specifications, engineering data, resulting from this expenditure of public funds should also be made available to the public. Appropriate payment, of course, could be exacted therefor, so that the Government could recapture from the entire industry the end results of the development and experimentation carried on with the public money. I might further suggest that the funds provided by the bill constitute a revolving fund so that the sums so recaptured would be made available for further experimentation and development.
I wish to thank you again for this opportunity to express the views of my organization.
John A. LAWLER.
President, Aeronca Aircraft Corp. Thank you very much.
The CHAIRMAN. We thank you very much. Senator Hunt, do you have any questions?
Senator HUNT. No, sir; I do not have any questions.
The CHAIRMAN. I want to place in the record a letter from Robert E. Gross, president, Lockheed Aircraft Corp.; also, a statement by Transcendental Aircraft Corp. of Delaware, by Mario A. Guerrieri; also, a letter addressed to me from the American Legion, signed by
Miles D. Kennedy, director, national legislative commission, with respect to S. 237, S. 426, S. 2301, S. 2984, S. 3504, and S. 3507; also letters from Eddie Rickenbacker, president of Eastern Air Lines; Edward F. Knapp, director of Vermont Aeronautics Commission; and Joseph K. McLaughlin, director, Department of Aeronautics of the State of Illinois; LaMotte T. Cohn, president, Consolidated Vultee Aircraft Corp., and C. C. Pearson, president of the Glenn L. Martin Co.
These letters will be placed in the record if there is no objection. (The letters are as follows:)
LOCKHEED AIRCRAFT CORP.,
Burbank, Calif., May 9, 1950. Senator EDWIN C. Johnson,
Senate Office Building, Washington, D. C. DEAR SENATOR JOHNSON: I have just read S. 3504 which you and Senator Brewster recently introduced in the Senate of the United States.
As you know, I have long been interested in the general subject of development of advanced type air transports, both because of their importance as an indispensable element of our military air forces and because of their importance to the economy of our country.
On previous occasions I have expressed to you my personal conviction and that of the Lockheed Co. that advanced type transport prototype development should be undertaken by the military services on the same basis that they sponsor the development of fighters and bombers. Moreover, it has been our position that unless the development of transport prototypes can be justified on a national security basis, there is strong doubt as to the propriety of the Government spending public funds for this purpose. For them to do so would tend to make the industry unduly subject to Government controls and even place it in jeopardy of ultimate nationalization which, in our opinion, would be a national disaster. For these reasons we have not supported the various prototype development bills heretofore proposed in Congress.
Senate bill 3504, however, represents an entirely different approach to the subject, and while we believe it provides only a partial solution to the financial problem of the aviation industry in producing jet type transports, it is certainly à step in the right direction and has our full support.
Although flight testing is a relatively small phase of designing, building and integrating new type transports, the knowledge that the Government has sufficient interest in advanced aircraft of this type to participate in the precertification testing does provide an incentive for private industry to undertake the hazardous venture of new aircraft development.
I feel that this bill, which I understand to be in general conformity with the proposals of the Air Coordinating Committee, is a constructive and proper step for our Govenment to take and that it will do much toward assuring continued American leadership in the air transportation field.
I want to express my personal appreciation and that of the Lockheed Co, for the valuable contribution you are making in the field of air transportation, and to offer any assistance I may give in bringing this proposal favorably before your committee and the Congress. Very sincerely yours,
ROBERT E. GROSS, President.
TRANSCENDENTAL AIRCRAFT CORP.,
New Castle, Del., May 9, 1950. STATEMENT OF COMMANDER MARIO A. GUERRIERI USNR OF TRANSCENDENTAL
AIRCRAFT CORPORATION IN REGARD TO BILL S. 2984 SENATE COMMITTEE ON INTERSTATE AND FOREIGN COMMERCE,
United States Senate, Washington, D. C. GENTLEMEN: It is now widely agreed that the long-heralded postwar air age has failed to materialize. After a brief boom in the sale of aircraft intended for private and commercial use immediately following the war, sales declined sharply and there is no indication that a reversal in this trend is imminent. The characteristics of present day light aircraft most universally held to account for the