Wednesday, January 11, 2012

1960: Aeronautical Research


1960: Aeronautical Research

Archives consist of articles that originally appeared in Collier's Year Book (for events of 1997 and earlier) or as monthly updates in Encarta Yearbook (for events of 1998 and later). Because they were published shortly after events occurred, they reflect the information available at that time. Cross references refer to Archive articles of the same year.
1960: Aeronautical Research
Aircraft Takeoff and Landing Modifications.
Aeronautical research in 1960 focused on projects to shorten required runway lengths and reduce airports of excessive size for aircraft of all sizes and mission profiles. STOL (Short Takeoff and Landing) and VTOL (Vertical Takeoff and Landing) projects moved from the drawing board to the experimental stage for civilian, commercial, and military use. Much of this work went unseen by the public, for the emphasis was upon experimental results rather than immediate implementation of research findings for operational use. Virtually every major aircraft company in the country was involved in programs to develop the short and vertical takeoff and landing abilities of aircraft.
Boundary Layer Control Project.
The Boundary Layer Control Project (BLC) came in for intensive experimental engineering application in the continuing industry-government program to reduce runway lengths for large aircraft. The key to the program in 1960 was a modified Lockheed C-130B Hercules turboprop assault transport of the Air Force. Two auxiliary jet engines pod-mounted beneath the wings provided boundary airflow over all control and lift surfaces for very slow flight and control. At a weight of 105,000 lb., the BLC C-130B landed at a speed of 70 mph compared to 105 mph for the unmodified transport, reducing the landing roll from a normal 1,800 ft. to only 450 ft. Moreover, pilots stated that even this amazing performance would soon be bettered. The unmodified C-130B stalls at 85-90 mph, but the BLC-equipped version could be stalled at only 50 mph, better than many small private airplanes.
Fighter Aircraft.
For the next-generation tactical fighter aircraft to follow the Air Force F-104 Starfighter and F-105 Thunder-Chief, the emphasis was placed on minimum takeoff and landing characteristics, and a new series of STOL and VTOL projects were inaugurated. The next tactical fighter airplane of the Tactical Air Command was committed to an STOL configuration, but the Air Force announced that there would be sufficient funds to continue design research on a VTOL fighter capable of Mach-3 speeds.
Engineers felt that special lift devices—rotary fans in the wings, deflected airflows, and other systems—must be implemented with a wing capable of variable sweepback to meet the requirements of specific speed regimes: minimum sweepback for slow speed, and a high angle of sweep for supersonic flight. The United States maintained a close working relationship with a West German group (Messerschmitt, Heinkel, and Bolkow) in developing a supersonic VTOL fighter for NATO. Bell Aerosystems Co. was invited by the German group to contribute its design experience from its own D-188A research project. And Fokker of Holland, designing its work activities around the successes of the Republic Aviation Corp., was preparing at year's end to submit to NATO a variable-sweep-wing, all-weather, supersonic VTOL fighter.
Because power requirements were more readily met with tactical fighters, large aircraft in the STOL and VTOL categories received less attention, although the military ordered a priority engineering study for the earliest possible development of a large, vertically rising transport for use by all three services.
Still another research effort in this area emphasized the drive to produce aircraft that are not dependent upon airfields. The Army Transportation Research Command, already engaged in studying many ground-cushion (aircar) designs for possible tactical application, announced a competition for a design study and preliminary design of a ground-effect takeoff and landing (GTOL) vehicle. The Vertol Division of the Boeing Airplane Co. was awarded the contract.
Jet Transport Developments.
The gains achieved in transport machines emphasized the fact that concern with the utility value of aircraft had replaced the desire for 'exotic breakthroughs' in research. The Boeing Airplane Co. moved toward the first flight test of the nation's first three-engine jet transport, its Model 727, with one engine mounted in a pod on each side of the tail, and a single engine mounted within the tailcone. Weighing 135,000 lb. and intended as a shorthaul jet transport, the 727 promised a new spectrum of commercial jet operations. United Air Lines was the first big customer for the new transport, with a tentative order for 40 Model-727 airliners.
Electra Modifications.
Through the separation of a wing in flight, two Lockheed Electra turboprop transports revealed in tragic fashion a hitherto unexperienced phenomenon of flight, induced by a combination of complex, interrelated factors.
Both airplanes that suffered wing loss in flight had previously been damaged by 'hard landings,' or some other factor, that caused damage to the wing mounts holding the two outboard engines in place. Under turbulent conditions at sustained high speed, the propellers underwent a rhythmic wobble; if the condition was severe enough and lasted long enough, the wobble was transmitted to the engine mounts and finally to the wings. In these two instances, when the damaged Electras flew at sustained high speed under severe turbulence the wobble became so severe that the 'torsion limit' of the wing was exceeded, and the wing separated from the airplane.
An order of the Federal Aviation Agency reducing the Electra cruising speed by 50 knots made the re-occurrence of the same factors impossible at this speed. Moreover, in the course of the reduced operations of the Electra, the airplane was modified to guarantee not only its original requirements of structural integrity, but also to increase its strength. Tests of modified Electras subjected the giant airliners to 'torture flights' under maximum loads, including vertical dives that yielded 'perfect structural integrity' results.
Turbofan-Engine Transports.
As 1960 came to a close, American Airlines was about to place in service its new turbofan-engine transports, improved models of its 707 and 720 airliners. The turbofan engine, which was lighter, more powerful, and more economical than previous turbojets, improved performance over a wide spectrum, in addition to promising quieter operation at airports where jet-engine noise has proved to be a major nuisance factor to homeowners living adjacent to the airports.
All-Cargo Airliners.
The jet transport category that promised to create a new transportation revolution, however, was the all-cargo jet airliner, rapidly nearing operational status. The demand for air cargo service increased to such an extent that an engineering program was initiated to eliminate unnecessary loading and unloading operations. The project resulted in the design and production of a 'swing-tail' cargo liner, in which the rear of the airplane is hinged, and swings completely to the side, thereby exposing the fuselage interior for rapid loading and unloading work. First into the air with a swing-tail transport was Canada, with its turboprop CL-44. In the United States, Boeing rushed development of a swing-tail 707 variant, and Douglas did the same with the DC-8.
Electronic Aids and Air-Traffic Control.
The entire aviation community moved rapidly toward a more wide-scale implementation of electronic navigational aids, and elaborate automatic air-traffic control systems. Under the FAA, an exhaustive program to modernize air traffic facilities, procedures, and rules promised greater safety in the context of an enormous increase in traffic density. Additional height-plusdistance radar, IFR (Instrument Flight Rule) equipment, homing devices, airport lighting, and other aids, considerably enhanced the ability of the airlines (as well as military, executive, business, and private aircraft) to operate with greater margins of safety under normal and inclement weather conditions.
Among other automatic and revolutionary electronic systems, substantial gains were scored in the development of special instrumentation for airliners that would permit completely automatic approach and landing. This new system involves 'hands-off' approaches in which the electronic-computer controls, 'locked on' to ground facilities, provide through a new automatic pilot system the necessary compensation for drift and crab as well as last-second corrective maneuvers prior to touchdown. An FAA C-54 four-engine transport completed nearly 1,500 'hands-off' approaches and landings without a mishap. This program, as well as others for the accelerated development of aviation aids, was carried out at the FAA's National Aviation Facilities Experimental Center (NAFEC) at Atlantic City, N.J.
Supersonic Aircraft.
Airliners.
The development of the supersonic airliner received greater impetus through the reinstatement of a major portion of previously canceled funds for the supersonic B-70 bomber program. Still in its infancy, the supersonic airliner faced a brighter future as a result of intensified interest on the part of both industry and government. The Weapon System 110 program (North American B-70 Valkyrie) called for the development of an XB-70 test vehicle, and three complete B-70 weapon-system aircraft. Capable of sustained flight at 2,000 mph at altitudes of approximately 75,000 ft., the B-70 will attack the myriad and complex problems of large-aircraft supersonic flight, especially in respect to heating and vibration. Although the major companies were advancing basic design proposals (Convair Division of General Dynamics, for example, offered a modification of its B-58 supersonic bomber as an interim testbed), the industry was agreed that the cost of developing a supersonic transport, capable of 2,000-mph flight over intercontinental range, must be shared between industry and government. Target date: Not before 1970-1975 for an operational supersonic airliner.
Thermal Barrier Research.
The problem of the thermal barrier, i.e., limits of operations of aircraft because of friction with the atmosphere, came in for steadily increasing research. While the thermal barrier constitutes a great hurdle for supersonic atmospheric aircraft, the problem is critical for the development of hypersonic machines (five times the speed of sound or greater), which include manned re-entry space vehicles that would function as aerodynamic, stabilized machines during re-entry and subsequent descent to a landing site. During 1960, intensive laboratory work was under way, as it has been for years, to develop heat-resistant metals, ceramics, and other materials, as well as special cooling structures and devices. One example was a special program of Bell Aircraft Corp., which was under Air Force contract to develop an insulated double-wall cooling structure for hypersonic aircraft operating as re-entry vehicles, or for high-speed supersonic vehicles sustaining maximum performance within the atmosphere. Basically, the structure consists of an outer-wall radiation shield and, separated by a layer of thermal insulation, an inner wall, which incorporates tubes through which liquid circulates to cool the airframe.
Rocket-Powered Aircraft.
Both atmospheric hypersonic vehicles and those with a dual mission of space-and-atmospheric performance moved from the research stage to active engineering status. Highlighting in-flight speed and altitude advances was the highly publicized X-15 rocket-aircraft program. Long delayed because of power-plant difficulties, the X-15, equipped with an interim motor, managed to reach new world speed and altitude records slightly higher than those established by the older X-2 research vehicle. These record-breaking flights established a clear path for flights with a 57,000-lb.-thrust rocket engine, which will bring the X-15 into its designed performance spectrum of 4,000 mph and altitudes of up to 500,000 ft.
All elements of the aeronautical and aerospace industry would benefit from the X-15's flights, but the one program immediately able to benefit from X-15 flight performance was the Dyna-Soar project of the Air Force. Although its mission profile called for performance in actual space, beyond the atmosphere, the go-ahead signal for the Dyna-Soar manned boost-glider vehicle signified the single greatest step forward for hypersonic aerodynamics. In order to fulfill its space mission, the Dyna-Soar must function as a winged aerodynamic vehicle from space during re-entry into the atmosphere and subsequent descent to the ground, passing down from hypersonic to supersonic and finally subsonic performance. The 'maximum priority' schedule for Dyna-Soar, as laid down in 1960, called for air drops of the Boeing-built glider, boosted by a modification of the Titan ICBM, from a B-52 sometime in 1963; launch of an unmanned vehicle in 1964; and the first manned shot by 1965.
Space Plane.
The single most exciting development in research was unquestionably the Air Force's Space Plane, a giant, manned winged vehicle which would race at great speed through the atmosphere while scooping up oxygen for use as an oxidizer for flight in airless space. Lockheed, Republic, Boeing, Douglas, and Convair submitted their design proposals to the Air Force. At the same time, the entire industry was closely watching the Marquardt Co., which in 1960 embarked on an exhaustive program for perfecting the technique of scooping oxygen out of the atmosphere and liquefying it for storage as a propulsion oxidizer in space.
Nuclear-Powered Aircraft.
Paralleling the stirring aerodynamic research events in other areas was the continuing research and development in the field of nuclear-powered aircraft, involving engine development in atomic turbojets and ramjets. The nuclear airplane moved closer to realization with problems encountered more in propulsion than in airframe development. Accelerated testing of various nuclear propulsion devices in remote areas produced outstanding results, and there were reports that a nuclear program for spaceships was proving successful beyond all expectations.
In preparation for the actual design competition to win the contract award, the major aircraft companies (some acting as teams in a joint effort) were busy designing a variety of proposals, all of which showed several basic similarities. The airplane would have to operate from existing airfields (just as the B-70 must operate from fields used by the B-52); the crew would be far removed and well-shielded from the reactor; the aircraft would be large, grossing from 225 to 300 tons; the first models would probably be subsonic; and the airplane would be able to remain aloft for five days of uninterrupted flight. The canard (tail-first) approach seemed the most promising, and experience here would be gained from the B-70 program.
Military Developments.
U-2 Plane.
The attention of the entire world was drawn to a research effort in aerodynamics that years ago moved into the practical phase, but had been withheld from the public for security reasons. The loss on May 1 of a U-2 reconnaissance plane over the heart of the U.S.S.R. revealed that Lockheed, by designing a high-performance sailplane wing around the turbojet engine, had produced an aircraft with unprecedented sustained altitude performance. With a 10,000-lb.-thrust J-57 engine, the U-2 could soar for hours at altitudes of 70,000 to 75,000 ft. With a J-75 engine of 16,000-lb. thrust, the airplane had a sustained cruise capability in excess of 96,000 ft., and reached its 'coffin corner' at approximately 100,000 ft.—a height at which thrust and lift could no longer sustain flight and the aircraft would suffer a high-speed stall. The success of the U-2 signified years of engineering design and a practical use of engineering factors to produce sensational performance.
Anti-Submarine Systems.
Less sensational but of equal value to military operations was the art of ASW (Anti Sub Warfare) as practiced by aircraft, and maximum priority was given to developing airborne systems to cope with a growing Russian submarine menace. In addition to new radar and electronic equipment placed in fleet operation, details of which were kept under the heaviest security restrictions, the single most outstanding addition to ASW capabilities was the development and production of specialized aircraft and helicopters with detection equipment. Supplementing this ASW capability was the production order by the Navy for a revolutionary AEW (Airborne Early Warning) aircraft, the Grumman W2F Hawkeye. The heavy, twin-engined machine uses an aircraft carrier as its home base. With its extensive radar gear, the W2F, operating in teams flying race-track patterns 200 mi. from a fleet center, enabled task forces at sea to be enveloped in 'radar cocoons.'
A vital military gain for combat capabilities of Air Force and Navy equipment came directly from the research laboratory. One of the major problems faced by the Air Force's high-flying bombers were the vapor trails (contrails) emitted by its jets, which visually marked the aircraft for many miles. A new process developed by the Cornell Aeronautical Laboratory reduced the production of contrails so markedly that they were invisible to the naked eye on the ground when the airplanes flew at 40,000 to 50,000 ft.
Other Aeronautical Research.
The diversity of aeronautical research was shown by the launching of a program designed to help an airplane create its own weather. The aim of this project, conducted with great promise by the Air Force's Cambridge Research Laboratories, was to develop airborne seeding equipment that would enable aircraft trying to land on fields covered with clouds—but not equipped with electronic navigational aids—actually to disperse the clouds. The aircraft would circle the airport and dispense dry-ice crystals into supercooled fog or stratus, producing gaps in the clouds that would then permit a visual approach and landing. Paralleling this work was a similar program in the U.S.S.R.
As part of Project Excelsior, the Air Force program to give life-saving equipment and procedures to pilots flying at extreme heights, Capt. Joseph Kittinger of the Air Force stepped out of an open balloon gondola at an altitude of 102,800 ft. to make an unprecedented parachute jump from an altitude of more than 19 mi.
Man—and not simply his equipment—proved able to cross the operational gap between atmosphere and space. It was an auspicious bridge to the coming year.


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