Within the Air Force the feeling has long been clear that the mixed force is necessary. A new manned bomber, to replace the aging B-52 force, is therefore a requirement.
Three systems are presently under study and in competition with one another to fill the advanced bomber role in the 1970s:
• A high-altitude, extremely-high-speed reconnaissance/strike aircraft.
• An advanced manned penetrator with variable-sweep wings—one that would attack at low level and high speed.
• A multipurpose, long-endurance aircraft, probably using laminar-flow control and regenerative turboprop engines.
There is a general air of optimism among most aviation authorities in USAF and the industry as to the technical feasibility of the next generation of strategic aircraft. But while the technical future is bright, management more and more becomes the critical factor in selecting the best and most reliable operational systems from the myriad possibilities.
Decisions will have to be made—and made soon.
The year 1964 is shaping up as a highly critical year for the Air Force. As a time for decision it can rival 1954—the momentous year in which the von Neumann Committee climaxed a long internal Department of Defense debate by stating flatly that an all-out effort to develop the ICBM could not be postponed any longer.
Just as the judgments of 1954 shaped the USAF’s strategic force structure for the entire decade of the sixties, so the decisions of the next twelve months seem destined to shape the strategic forces of the 1970s.
Today’s central question is whether the Air Force will continue to operate a “mixed” strategic force of manned aircraft and missiles, or whether it will rely more and more on missiles. Certainly there can be no doubt as to the military’s position on this issue. If complete reliance on missiles ever was argued seriously within the Air Force, that debate is long past, and it resulted in a solid judgment that a mixed force is necessary to provide the strategic options necessary for a clear military superiority.
And, as in the past, the Air Force solidly advocates a clear military superiority as the only positive means of maintaining the peace, making nuclear aggression against the US and its allies unthinkable and providing a position of strength from which negotiations with the Communist bloc may be conducted.
Specifically, the Air Force wants a new manned bomber to replace the B-52 force, which is wearing out and against which the Soviets have had ten years to prepare defenses.
USAF’s views on a new bomber and a mixed force for the 1970s are getting an exhaustive and responsive hearing from the Office of the Secretary of Defense (OSD). Top defense officials who criticized the manned bomber as “inflexible” and “quite vulnerable” to surprise attack during the budget hearings last January and February appear to be approaching the question with more open minds.
Briefings have been under way for some time, and the current feeling seems reflected in a recent statement by Dr. Harold Brown, Director of Defense Research and Engineering, before a Senate committee. Dr. Brown said, “There is no assurance that we will have follow-on bombers. But I think there may well be.”
The briefings are scheduled to continue through early summer, at which time the OSD is expected to reach a position. This would be early enough to influence the FY 1966 budget.
The long-term Air Force-DoD discussions reflect the difficulty of the upcoming decisions. Unfortunately, the strategic force question in 1964 is much more complicated than it was in 1954.
‘An Embarrassment of Technical Riches’
First of all, any new system will be extremely expensive. It would undoubtedly cost upward of $15 billion to develop, manufacture, and operate any system that would be relatively as effective in the 1970s as the B-52 force is today.
Understandably, no program of this magnitude is going to be undertaken without the most thorough justification and review. Any system selected for development must have a very high probability of becoming extremely reliable and effective.
Exploding technology, even more than high costs, is complicating the strategic-weapon debate. Today there is no relatively simple go or no-go decision on a single weapon system. Technology, in its relentless growth, has brought many new weapon concepts—some of which were little more than dreams in the early 1950s—to the point that they are widely considered to be practical today. Dr. Alexander H. Flax, Assistant Secretary of the Air Force for R&D, says that we are faced with an “embarrassment of technical riches.”
Gen. Bernard A. Schriever, Commander of the Air Force Systems Command, has reported that one panel working on the report for Project Forecast, USAF’s searching look into its own technical future, has identified more than forty possible types of future military aircraft systems. A number of these are strategic aircraft. In addition, there are numerous advanced unmanned systems with which the strategic aircraft must compete. Systems now under study and considered feasible include unmanned intercontinental hypersonic glide vehicles and long-range, low-level, very-high-speed cruise missiles, powered by either nuclear or chemical ramjets.
Each of these systems has unique advantages, and each can pose serious problems for the defense. However, the proliferation of possibilities has deepened the uncertainty as to just how any system will fit into the operational military realities of the 1970s and the early 1980s.
Consequently, technical opinions differ widely, and there is no unanimous clamor for any one offensive weapon as there was for the ICBM. Advocates of a new manned system are split among several types of possible future bombers. And there are many informed persons who are not yet convinced that the next major weapon system should be manned at all.
Case for the Manned Bomber
Arguments for a new manned bomber for the 1970s have been expounded by most of the USAF’s top uniformed leaders during the past year. Their key point, in essence, is that aircraft are more flexible than missiles. And in an uncertain future this flexibility would allow the manned aircraft to meet a wider variety of unpredictable threats.
One of the most recent statements was made by General Schriever at a joint meeting of the American Institute of Aeronautics and Astronautics and the USAF’s Aeronautical Systems Division in November. At that time he said, “Manned and unmanned systems each possess their own unique advantages. It is pointless to talk of one ‘replacing’ another. . . . Aircraft offer the flexibility . . . rapid mobility . . . and high degrees of control . . . we need to apply the precise degree of force needed to any level of threat, anywhere in the world.”
Gen. Thomas S. Power, Commander in Chief of the Strategic Air Command, at the AFA Symposium on Manned Aircraft Requirements in the 1970s last September, voiced two other justifications for the manned bomber. General Power said, “There are uncertainties concerning the effect of high-yield nuclear weapons on our missile sites which will have to ride out the initial attack. . . . That is the primary reason why I see a continued need for manned aircraft.” General Power also pointed to the “greater reliability” of the manned aircraft because it can be subjected to extensive operational testing which greatly enhances the discovery and correction of technical deficiencies.
In addition, General Power answered critics who contend that the manned aircraft has reached the end of the line and has become too vulnerable to modern air defenses. According to the SAC Commander, hydrogen bombs delivered against the defensive system and its radar net by the first wave of ICBMs and bombers will make penetration possible. He said, “The defenses have improved. In the last war we did not target them . . . but they are targeted today and they are way up on our target list and we would like everybody in the world to know that . . . There is absolutely no question about our ability to destroy any target on that target list today.”
Three Systems Under Study
In the final round of briefings and discussions with the OSD, the Air Force is basing its case for the manned strategic bomber primarily on three detailed systems studies which are due to be completed next spring. These study aircraft which are in competition for the advanced bomber role concern:
• High-altitude, extremely high-speed reconnaissance/strike aircraft. McDonnell Aircraft Corporation and Lockheed Aircraft Corporation are both engaged in USAF-sponsored studies of this type of vehicle which currently is called the RX.
• Advanced manned penetrators (AMP) which would cruise out at high level and fly at low level and high speed during the last few hundred miles to the target. This aircraft undoubtedly would need variable-sweep wings for it is to perform essentially the same mission as the TFX but stretched to intercontinental ranges.
This capability for high speed on the deck should enable this aircraft to cruise continuously at supersonic speeds at altitude with little performance penalty in other areas. General Dynamics Corporation, the Boeing Company, and North American Aviation, Inc., are conducting such studies.
• Multipurpose, long-endurance aircraft called MPLE or Maple. A wide variety of these multiple-purpose aircraft is possible, and they seem adaptable to several other tasks in addition to the strategic. Endurance versus speed appears to be the most important trade-off. For instance, if several days of endurance are provided, the aircraft probably would have to be driven by regenerative turboprop engines turning very-large-diameter propellers. If more speed were desired, turbofans or turbojets would be used, and the propulsive efficiency and endurance would drop. A major strategic advantage of the very-long-endurance Maple is that it could circle existing air defenses and could approach the Eurasian land mass from any direction with air-launched missiles. Several companies are working on studies of this type, with virtually all of them using the Northrop-developed laminar-flow control, low-drag boundary-layer control system (see Am FORCE, August ’63, pg. 31).
All of these design studies are of the parametric kind and investigate the influence of a wide variety of factors on the performance and effectiveness of each type of aircraft. For instance, the advantages and disadvantages of aluminum, titanium, and steel structure and turbofan versus turbojet powerplants are looked into in detail. Variations of each type of engine and structure also would be studied, with each variation pushing the “state of the art” a little differently—or not pushing it at all.
The Coming Boost in Effectiveness
In general the ground rules in these studies call for the use of technology that either has been proven on operational airplanes or has been the subject of extensive applied research. This means that the projected new aircraft would make some use of the new lightweight engine technology (see “The Coming Revolution in Jet Propulsion,” Am FORCE, October ’63, pg. 36); major aerodynamic developments such as the variable-sweep wing (see “Progress Is a Variable,” Am FORCE, November ’61, pg. 46), and the laminar-flow control system, and would be made out of either aluminum, titanium, or steel structure. There is no doubt that the technology is immediately available to build aircraft that are much more effective than those in service today. And there is every reason to believe that the boost in effectiveness for the next generation of strategic aircraft would be by far the biggest ever achieved.
Most aviation authorities in the Air Force and industry are optimistic about the chances of demonstrating this boost in effectiveness to the Department of Defense. Dr. Flax reflected this general optimism recently when he said, “It is obviously too early to prejudge the results of the detailed studies [the three mentioned above], but I believe that it will be possible to show that a new manned strategic aircraft will make a substantial contribution to our total military strength, particularly when the entire spectrum of warfare and the entire spectrum of military missions, rather than only the massive nuclear exchange, are considered.”
A key element in Dr. Flax’s optimism is that the new technology apparently will allow the next generation of strategic aircraft to have a STOL (short-takeoff-and-landing) capability without a significant impairment in range or cruise speed. The use of high-lift boundary-layer control and engines with vectorable-thrust nozzles and increased thrust-to-weight ratios offers the possibility of cutting the takeoff distance on a 250,000- to 400,000-pound jet aircraft from today’s requirement of around 10,000 feet to the neighborhood of 5,000 feet.
Since there are only a few airfields in the US with runways 10,000 feet or longer it hasn’t been possible to disperse SAC bombers widely on the ground. Consequently, the force cannot have an acceptable survival probability without maintaining an airborne alert that is very costly and wearing on crews and equipment. The B-52 force’s current ability to survive a massive attack and then retaliate effectively has been seriously questioned in DoD by critics of the manned bomber. This criticism would be largely overcome if SAC bombers had a 5,000-foot STOL performance. Then they could operate from any of more than 1,000 US airfields, and their survivability would be increased significantly.
Dr. Flax attributes additional benefits to the STOL idea. He says, “This, if you like, would be long endurance on the ground rather than long endurance in the air. It would probably be far less expensive both in first costs and in operational costs. . . . Such aircraft would be easily operable from a variety of overseas bases, if such a mode of operation became militarily or politically more effective. While such a strategic aircraft would appear to be far less exotic than many of those claiming current interest, it might well prove to be the more practical, more economic, and more militarily effective.”
Bright Technology Ahead
The rapid expansion of technology in every field has had two chief effects on the immediate future of manned aircraft. One tends to brighten the picture and the other to dim it.
First, today’s technology is so attractive that few doubts are left that a new generation of aircraft would be superb performers. However, by all reports the technical revolution is still picking up speed, and it is not difficult to make reasonable extrapolations of today’s technology and show that if development could be postponed four or five years, much better aircraft could be built.
Most Air Force and industry leaders believe that such a delay would greatly lower the efficiency and erode the expertise of both design and management teams, but this is an opinion that they must prove to top management in DoD. The applied-research payoffs that seem possible in the relatively near future are extremely attractive. Their revolutionary nature can be illustrated by two recent statements.
General Schriever, in discussing the Project Forecast studies, said, “We have identified new materials that are stronger, lighter, stiffer, and able to withstand high temperatures. For example, new types of metallic fibers may be feasible in forming extremely strong, lightweight composite structures. If such projected applications prove to be practical, then we may be in for a revolution in aircraft design and fabrication.”
Thrust-to-Weight Ratios
Dr. Flax has made some extremely encouraging predictions about the thrust-to-weight-ratio (T/W) improvements to be expected for gas turbine engines. The T/W is a key factor in providing VTOL capability and in improving top speed, maneuverability, and range performance in aircraft. Dr. Flax says, “It is possible today to begin the development of lightweight lifting engines with a T/W of 20 to 1.” The installed T/W of these lifting engines would be about 16 to 1 when supporting structure and all accessories are considered. Cruise engines which operate the entire time an aircraft is aloft, instead of only during takeoff and landing as do pure-lift engines, probably would have installed thrust-to-weight ratios of better than 10 to 1, compared to well under 7 to 1 for any engine today.
However, the next generation of 20 to 1 engines is far from the end of possibilities currently in sight. Dr. Flax says, “Applied research now in progress makes us believe that the second generation of future engines will have installed thrust-to-weight ratios of about 30 to 1.”
This prediction means that there would be an extremely small penalty to pay for making any aircraft VTOL. It also means that cruise engines would have installed T/Ws of well over 20 to 1. They would m aircraft lively and maneuverable beyond the fondest dreams of today’s pilots. Estimates of this type le no doubt that the technical future of aviation n has been brighter.
The potential is so bright for all phases of technology that management more than ever has become the critical factor in creating sound, reliable operational systems from the myriad of possibilities. Certainly one of the clearest lessons of the past fifty years is that not all apparently promising technical possibilities will be fruitful and that it takes money to find out what will work and what won’t. As the number of possibilities continues to grow, the art of successful management seems to depend upon creating a low-cost method for determining at a very early stage just what elements of advanced technology will work and what won’t.
Build and Test Prototypes
Dr. Flax suggests that the cheapest and most certain means of accomplishing this is to build and test prototypes. Prototype development, according to Dr. Flax, should properly be used to prove out the more advanced technical possibilities, or second-generation technology such as turbojets with thrust-to-weight ratios of 30 to 1, supersonic combustion ramjets and aircraft that fly above Mach 5. He says, “We can’t answer all the important questions regarding such devices on paper or through small-scale research. It would be very risky to push any of them into a systems-development program without prototype testing. Prototype testing appears to be the cheapest and quickest way to explore the range of technical possibilities.”
Dr. Flax would confine full-scale systems development to more proven technology such as that involved in gas turbines with 20 to 1 thrust-to-weight ratios and the RX, AMP, and Maple aircraft concepts.
Proposals for major management changes, such as a partial return to the prototype system, are not unique to Dr. Flax. Other officials in the Administration, in the Air Force, and in industry are known to be looking for less expensive means of determining exactly what can be done with the new technology. A variety of methods are being considered such as a simplification of the DoD and USAF reporting procedures and a relaxation of military specifications for prototype development so some of these vehicles would actually be little more than shells intended to prove primary performance such as top speed, drag at cruise, etc.
The clamor for management changes to allow a more thorough probing of the new technology is almost as strong as the desire for a new manned bomber in the Air Force and industry. Both of these questions apparently will be settled during 1964. None of the Kennedy Administration’s decisions to date will have more influence on the long-range US strategic posture, the type of organization the Air Force will be in the 1970s, and the capacity of US industry to build superior aircraft.