Systems affordability clearly is more than a short-lived buzz word. Latest Defense Department compilations show that overall cost growth for major weapon systems is approaching an annual level of twenty percent, fed by inflation, a shrinking base of subcontractors, depressed buy rates, and increasing shortfalls in technically trained personnel. The formula for alleviating these assorted ills is diverse, complex, and in some aspects, radical.
Since labor-intensive operations detract from productivity and profitability, they are key targets in the drive toward systems affordability. Techniques that stress materials forming and bonding in place of labor-intensive riveting and advanced automation schemes are obviously part of the answer. New materials technologies are another.
There is evidence that the manufacturing of composite materials is approaching a level of maturity that might take them out of the limbo of costly experimentation and permit their widespread use in airframes of all types. To date, the great expectations associated with almost two decades with advanced composites have proved elusive, largely because too much hand labor goes into the manufacturing process. Compounding the problem is a vicious-circle syndrome, meaning that because of their high manufacturing costs, composites are being confined to narrow applications in airframe skins; but by limiting demand for composite materials industry has only limited incentive for investing in efficient mass production processes. The Aeronautical Systems Division, therefore, is providing seed money for the development of optimized composites factories. Northrop Corp., for instance, has been commissioned to carry out basic research on how to lay out such a factory, with emphasis on thoroughly automated processes. This $2.2 million study is to be completed by September 1982.
The underlying objective is to achieve manufacturing efficiencies and economies that make it attractive to use advanced composites in airframe structures on a large scale. Clearly, it will take a good deal of investment at high risk to bring about efficient, automated composites manufacturing plants. Military as well as commercial aviation probably will have to join forces and provide the needed risk capital, General Skantze suggests.
For the time being, the ASD Commander admits, use of advanced composites in aeronautical engines does not look promising. Eventually, however, such composites materials as carbon/carbon laminates—developed for nozzles of ICBMs and SLBMs—might become usable in the hot sections of aircraft engines.
Another area of manufacturing modernization that in General Skantze’s view shows great promise is a combination of computer-aided design and manufacturing into a cohesive, streamlined process. Two payoffs accrue from this approach. The computer can be used to design and manufacture components in an optimal manner. Further, because the process is fully automated, it is “not only repeatable but the quality could be close to 100 percent,” the ASD Commander said. Although the prospects for modernization and productivity gains are great, General Skantze cautions that aerospace is only a small portion of the market and thus can’t bring a reindustrialization of America singlehandedly.
Cracks in the Industrial Base
Also, the drive to rejuvenate aerospace manufacturing and increase productivity is not likely to reach fruition as long as investment spending remains at the present relatively how levels. The problem is not being helped by weaknesses in the industrial base. The Senate Armed Services Committee, for instance, recently projected a rather sobering view of trends in the defense industry, asserting that “many potential suppliers of defense material are giving increasing emphasis to commercial contracts that appear to offer better opportunities for profit and business stability than cyclical defense business.” Pointing out that for the first time since World War II commercial aircraft production now exceeds that of the Department of Defense, the committee found that “the delivery schedules of entire weapon systems have been affected by serious bottlenecks in forgings and castings, optical components and sensors, and semiconductors.”
Lastly, the Senate Armed Services Committee warned that “significant shortages of and dependence on overseas sources for key raw materials—especially cobalt, titanium, and asbestos—and semifinished commodities are also impacting o the pace for the US defense program, especially because of the demands of high technology for exotic materials.”
Yet another factor aggravating this condition s what Rep. James D. Santini (D-Nev.), Charirman of the House Subcommittee on Mines and Mining, terms the “resource war” that is being waged by the Soviet Union. That country, he charged during recent subcommittee hearings, “has moved into the international resource arena armed with a strategy that extends beyond economic competition but falls just short of conventional military conflict.” Increasing domestic consumption combined with a “rapidly deteriorating mineral resource position” changes the USSR from an exporter to an importer of nonfuel minerals, thus causing the Soviet Union to resort to “economic cannibalism designed to destroy the process of economic activity” of the free world, he warned. Manganese, an essential ingredient in steel making, for instance, is one of the vital minerals that is being kept off the world market by the Soviets, he charged.
Boeing’s Chief Executive Officer T. A. Wilson told Representative Santini’s subcommittee that the raw material problem of defense industry is becoming acute, with some of the materials in short supply coming almost solely from foreign sources in politically vulnerable areas. “We need to improve substantially our strategic stockpile and its management,” the Boeing executive testified.
While there are no easy or quick solutions to the scarce materials problem, considerable progress is being made in new metal alloys forming processes that result in “superalloys,” potentially capable of being substituted for scarce, exotic metals such as cobalt.
A key example of USAF’s spartan “make-do” approach is the KC-135 reengining program that was launched in January 1980, with a contract award to Boeing covering relevant research and development. USAF’s present inventory of KC-135 tanker aircraft stands at 642. As OSD and Air Force witnesses testified before Congress, the aircraft can be expected to last well into the twenty-first century. But the J57 engine on the aircraft was designed in the 1950s and its marred by high fuel consumption, high noise, high emission of pollutants, and low power output.
By reengining the KC-135s it is possible to boost the aircraft’s offload capability and assure its viability for years to come. Dr. William J. Perry, Under Secretary of Defense for Research and Engineering, told Congress earlier this year that KC-135s using the CFM56 engine (jointly developed by General Electric and SNECMA of Paris, France) score fuel offload increases of between thirty to 200 percent over the conventional model. Additionally, if, as currently proposed, 300 KC-135s are eventually reengined, fuel consumption can be cut by about 100,000,000 gallons a year because of the high fuel efficiency of the new power plant.
But, as Gen. Lew Allen, Jr., USAF’s Chief of Staff, points out, “While the fuel savings associated with reengining are significant, the primary justification for this program is the additional aerial refueling capability that could be generated.” The latter, he stresses, “is necessary to support not only our strategic bombers but also our airlift and tactical fighter forces.” By 1990, according to detailed Air Force studies, aerial refueling requirements will be about twice the present capability. Increased refueling requirements result in part from the increased drag imposed by the air-launched cruise missiles (ALCMs) that will be deployed on B-52s over the next few years, according to Dr. Perry.
Yet another important plus is provided by the reengined KC-135. Its takeoff roll can be cut by as much as fifty percent to permit operation from shorter runways in NATO areas or US dispersal bases. Cost of the modification, according to Dr. Perry, will be amortized over a period ranging from eight to seventeen years, depending on the number of aircraft modified and the price of fuel.
Cost of the modification, according to current estimates based on a program involving 300 aircraft, should be about $17.5 million per aircraft. This figure includes cost of the engine—a dual-rotor high bypass ratio turbofan—as will as beefed-up landing gears and a larger horizontal stabilizer.
Installation of CFM56 engines on a KD-135A will get under way in 1982 and is to be followed by testing at the Air Force Flight Test Center at Edwards AFB, Calif., and operational testing elsewhere.
Tactical Aircraft Plans
Although there is no immediate requirement, the Air Force is keeping open a number of options to develop a new tactical aircraft. Included here are derivatives of existing aircraft as well as an advanced technology design. (Whether or not the so-called “Stealth” technology is included can’t be discussed for security reasons.) Among the derivative designs is an enhanced F-15 tailored for the air-to-ground role. This project is funded mainly out of pocket by McDonnell Douglas and its associated contractors. General Dynamics, in similar fashion, is working on an enhanced F-16XL, which uses a delta wing. Lastly, Fairchild is proposing a two-seat version of its A-10 for the night attack role. USAF’s reaction to the latter remains lukewarm, primarily because of the additional crew requirement.
So far as V/STOL is concerned, the Air Force’s attitude remains largely skeptical, although pertinent studies involving TAC and ASD continue. As General Skantze explains, V/STOL must be viewed in a total tac air force structure context. The pivotal question, he said, is whether V/STOL “could become an overall requirement, particularly in Europe. For the time being, that isn’t necessarily so.” Militating against V/STOL, he suggests, is that both the F-15 and F-16 are “high-performance aircraft that can get off the runway quickly. They can even stop short.”
In the case of the A-10, it is possible to use JATO (jet-assisted takeoff) units on two of the aircraft’s weapon stations to get off the ground rapidly and with an extremely short takeoff roll. Because of the interdependence of all elements of the tactical force structure, it would not make much sense to convert only one component of the force structure to V/XTOL and not the others. In a practical sense, for instance, a V/STOL close air support component that depends on air-superiority fighters lacking that capability is a “nonstarter,” General Skantze stresses, adding that the advisability and feasibility of building V/STOL air-superiority fighters, at best, appear questionable.
The F-15 as a CONUS Interceptor
So far as CONUS air defense requirements are concerned, General Skantze suggests that the F-15 equipped with Advanced Medium-Range Air-to-Air Missiles (AMRAAMs) “could be able to do the job. This combination could result in a good, long-range interception system with semiautomonous capabilities.” The F-15, he adds can carry a large number of these missiles, and with its upgraded radar system can engage up to four targets simultaneously. The F-16, in combination with AMRAAM, also becomes “a potent” interceptor, but is handicapped in relation to the F-15 because it lacks a search radar. Key features of AMRAAM, which is currently in a competitive validation phase involving Hughes Aircraft and Raytheon, are its ability to operate both within and beyond visual range, high average velocity, launch and leave, and multiple target attack.
Even though the AMRAAM missile won’t reach production status until 1984, options for eventually enhancing its performance are under way already. A major concern is with enhancing “end-game” performance, meaning the missile’s ability to perform high G maneuvers as it closes on its target. Two technology efforts focus on this requirement, with special emphasis on high-altitude and extended-range performance. One project centers on the development of ducted rocket motors (DRM), and the other is known as the Technology Integration of Missile Subsystems (TIMS) effort, DRM, which is a special form of ramjet, includes both fixed fuel flow approaches to provide high initial speed with low thrust levels for long times of flight with high terminal maneuverability as well as variable fuel flow to extend range and enhance high-altitude performance. TIMS, as its name implies, concentrates on refining missile components, including the use of lifting body airframes to increase G capability.
The AFTI Program
Key technology demonstrations by the Air Force, the Navy, and NASA with potential for applications in the next generation of tactical combat aircraft are channeled into AFTI, the Advanced Fighter Technology Integration program of AFWAL’s Flight Dynamics Laboratory at Wright-Patterson AFB, Ohio. (Congress last year canceled the Enhanced Tactical Fighter program—meant to achieve evolutionary improvements of existing technology relatively quickly—and recommended instead that USAF and the Navy concentrate on technology options for a new fighter for the 1990s.)
AFTI’s goal is broad: To look for, validate, and demonstrate those technologies—and their integration—that improve subsonic and transonic maneuver, tracking and kill capability in air-to-air and air-to-ground combat, and boost aircraft survivability. Although extensively revamped since its beginning in the mid-1970s, AFTI continues to pursue its objectives along several paths. Funded at a modest $10.5 million in FY ‘81, the program’s budget is to grow to $30.2 million in FY ‘86.
One of the program’s three principal components is AFTI/f-16. Serving the Air Force as well as the Navy and NASA, this project was launched formally in December 1978 to develop and demonstrate an ambitious set of new technologies by 1984. Among the project’s objectives are development of advanced, multimode digital flight controls and their subsequent integration with sophisticated fire-control systems; advanced control modes encompassed such “nonclassical” flight vehicles as CCV (control configured vehicles) and direct side force and direct lift control; and improved pilot/crew-station interfaces.
Nonclassical flying goes back to the Wright brothers, but in a practical sense is rooted in the fly-by-wire (FBW) primarily flight control technique, a closed loop information system that continuously feeds back into the flight control computer cockpit data from an aircraft’s motion sensors and transmits electrical wire harnesses. In place of the conventional center stick there is a small sidestick control that serves as the “impute” to a flight control computer that processes and modifies this information, combined with data from the control surface sensors. The computer’s output then “flies” the aircraft.
Reliable fly-by-wire control opens the door to designs of relaxed static stability, a key element of nonclassical flying. A stable airplane returns to level flight after a disturbance; the unstable airplane does not. If turbulence raises its nose, for instance, the aircraft will continue to climb more and more steeply. The stable airplane obviously is easier to fly, but it exacts a high price for its predictable aerodynamic performance. Inherent stability requires increased fuselage length and large tail surfaces, thereby increasing drag and reducing maneuverability. A number of techniques have evolved for providing unstable flight vehicles with artificial stability. In the process, performance under all flight conditions and speed regimes is improved.
Among the most drastic and revolutionary advanced control modes pursued by AFTI-F-16 are direct side force and direct lift control, fuselage aiming or “decoupling,” and weapon line pointing. These techniques make it possible through closely coupled interaction of sophisticated vertical and horizontal control surfaces to point the aircraft and its weapons in a direction different from its flight path or to adjust its flight path laterally or vertically without having to rotate pitch, yaw, and roll axes of the aircraft. The result is that the aircraft’s flight path—or the relationship between its longitudinal axis and its flight path—can be changed without pulling Gs. In terms of defensive capability, an aircraft with direct force control and fuselage decoupling is an extremely elusive quarry for both enemy fighters and SAMs.
Applied to offensive tasks, a fighter using these features, once locked on a target in the air or on the ground, can utilize fuselage pointing to maintain attack positions for long periods of time and with a wide choice of attack flight paths.
Coupled with a digital flight control system, these performance gains can be further magnified. The AFTI/F-16’s digital computer, a Bendix 930 processor, enables the pilot to tailor the control system to a range of flight modes and tasks, including, eventually, weapon selection, sensor video, and radar mode. Once matured, this combination of technologies should enable a pilot who is getting jumped by “hostiles” to simply punch the “air-to-air” mode button on the computer rather than having to go through the complex and cumbersome procedures of present-generation fighters.
The first phase of the AFTI/F-16 program concentrates on integration of the advanced digital flight control system with aircraft avionics. The second phase involves adding sensor systems and integration of the flight-control system with the aircraft’s fire-control system. Subsequently, the aircraft’s air-to-air and low-level weapons delivery capabilities will be tested at the Red Flag facilities. The Navy’s primary short-tem interest in the program is in exploring the potential of digital flight controls for future V/STOL designs.
The AFTI/F-16 is undergoing modification at General Dynamics’ Fort Worth, Tex., plant and is scheduled to begin flight testing at Edwards AFB, Calif., in July of next year.
Other AFTI Elements
Another key element of AFTI is the AFTI/F-111 (Mission Adaptive Wing) project. The objective is to develop and test smooth, variable-camber wings on an F-111 test-bed and to make this technology with a digital control system that optimizes wing camber automatically for various flight conditions. Major payoffs from this technology are improved cruise efficiency and greater maneuverability. First flight of the aircraft using manual variable-camber control is slated for August 1982. The AFTI/F-111 is to flight-test variable camber under automatic control in FY ‘84.
The Mission Adaptive Wing eases a fundamental problem of conventional airfoils: because of the cambered configuration of aerodynamic lifting surfaces, the airstream flowing over those surfaces can reach sonic speed even though the vehicle is flying in a transonic range. This can occur at speeds as low as Mach 0.70 and causes a standing shockwave. The results are airflow separation, an increase in drag, and buffeting. Considerable progress is being made in combating the so-called shock-boundary layer phenomenon through advanced airfoil shaping, such as the supercritical wing, which pays off through less drag and buffeting and thus greater range, better fuel efficiencies, and the ability to fly faster transonically.
The Mission Adaptive Wing takes aerodynamics into a more advanced realm. Present technology compromises wing shapes in some flight modes in order to optimize them for others. At present, the only technique for changing wing camber is through leading edge slots and trailing edge flaps, slots, and slats. But these devices cause high drag and aerodynamic flow separation because they are uneven. By contrast, the ideal wing should be variable yet have smooth contours. Further, such a wing should provide high camber at low-to-medium subsonic speeds, become supercritical (or “sloped rooftop” airfoils) at transonic speeds, and changed to essentially symmetrical airfoil configuration during super sonic flight. Hence the Mission Adaptive Wing involves an arrangement of flexible skin covering, a mechanism that can be deflected mechanically. The resulting wing system can be essentially redesigned in flight, either by the control system or the pilot.
The third major element of AFTI is a conceptual follow-on to the two projects in progress. Concept definition of this project is to start in FY ‘82. The range of technologies are to be demonstrated. Key objectives here are STOL (short takeoff and landing), rough-field landing gears, and low speed/high angle of attack control and lift.
This program may also demonstrate the so-called 2-D, for two-dimensional, vectoring, and reversing nozzle. Maneuverable and integrated with the airframe, a vectoring nozzle can apply thrust in directions different from the longitudinal axis of the aircraft. Its possible benefits, broadly, are lower drag because of high streamlining; improved lift and reduced takeoff and landing distances because of thrust vectoring and reversing; and higher combat maneuverability, also due to thrust vectoring or modulation in the instantaneous maneuvering regime.
Related work in progress at AFWAL’s Aero Propulsion Laboratory and NASA—although not part of AFTI—involves variable cycle engines that modulate bypass ratios and other functions. The pilot, thus, can optimize engine performance for a range of prevailing flight regimes, from takeoff to subsonic or supersonic conditions. This program, in concert with the multifaceted AFTI project, is building a technology base that should enable the Air Force to gestate within a few years a dramatically new fighter aircraft of unmatched performance.
Return of the RPVs?
Few aerospace technologies have had more violent ups and downs than the field of RPVs (remotely piloted vehicles). Germinated by an AFSC-funded Rand study of a decade ago, RPVs burst upon the scene larger than life size as the answer to nearly all things aeronautical. But the dream of low-cost, invincible air-superiority fighters and of hordes of superefficient close ground support systems, all controlled remotely and without risking human life, began to falter in the mid-1970s after some brave starts and critical successes, such as the Compass Cope long-endurance, high-performance RPV.
Postmortems by congressional committees tend to attribute the reasons for this disenchantment with RPVs to greater than anticipated costs and technological difficulties. Clearly the set-up from preprogrammed reconnaissance drones that proved so successful during the Southeast Asian war and elsewhere to RPVs “flown” in real time by a remotely located pilot has proven more difficult than originally assumed. But after several years in suspended animation, unmanned automatic vehicles—in fact, “smart” drones rather than RPVs in the classical sense—may be getting their second wind. The weapon system that may become the progenitor of a family of sophisticated drones is Locust, a miniature harassment vehicle under joint USAF/German Armed Forces development. Locust, according to General Skantze, represents “a very serious and perhaps the first real commitment to integrate RPVs into USAF’s force structure.”
The Air Force “might acquire between 5,000 and 10,000 units, if we indeed can come up with a low cost harassment vehicle that autonomously targets itself against emitting radars,” he said. The ASD Commander pointed out, however, that the tendency to maximize the Pk (probability of kill) of any given Locust vehicle—and hence to drive up unit cost—might endanger the program. These ground-launched weapons, in effect sophisticated model airplanes equipped with a warhead, are preprogrammed to fly into specified target areas, where they loiter until their sensors detect a radar emitter. Once they do, they ride the radar beam into the target and destroy it. The hostile radar’s only real “countermeasure” is to go off the air. Either way, Locust achieves its objective, which is to put the enemy’s ground-based air defense system out of commission to give the ingressing friendly fighter force a free ride. ASD’s assessment is that if only every third of these vehicles actually achieves a “kill,” they will by sheer weight of numbers “literally shut down the other side’s radar system.” The flyaway unit cost goal of the Locust program, General Skantze said, is set in the $14,000 to $15,000 range. Source selection of a joint US/German contractor team to build Locust is underway.
Locust appears capable of adaptation to a range of other targets, including tanks and aircraft on the ground. Since this minidrone is built of largely non metallic materials and is, therefore, almost impervious to radar detection, it could be said to be a Stealth design. Locust’s quality of launch from the rear echelon, flying to orbits over preselected target areas, and then conducting autonomous search, make it attractive eventually to couple the weapon with a variety of sensors.
Air-breathing Strategic Systems
Nowhere is ASD’s quandary over having to balance out—within constrained budgets-short-tem “fixes” against long-term “cures” more acute than in the strategic sector. The imperative of keeping the B-52 viable as a multirole weapon system in the face of increasing threats and aging falls into the former category. While Congress has given the Administration a mandate to bring a new multirole bomber into the inventory by 1987, such a weapon system, even under the best of circumstances, is not likely to achieve full operational status until about 1990. Additionally, there is increased expectation on the part of the Defense Department and the Air Force that the B-52 will serve as USAF’s principal cruise-missile carrier well into the 1990s. As a result, ASD is carrying out a $2.6 billion modification and modernization program involving about 170 G and ninety-six H models. A key element of this program is an offensive avionics update that will correct bombing navigation system reliability and maintainability problems, increase weapon system effectiveness, and provide a launch platform for ALCM. First test flight of a B-52 retrofitted with the upgraded avionics suite occurred in September.
Additionally, 120 G models are being modified to serve as cruise-missile carriers. Modification entails the installation of pylons needed for external carriage of cruise missiles, enlarging of the weapons bay, and the addition of strakelets.” At the insistence of the Soviet SALT II negotiators, the strakelets—which enable the USSR’s intelligence systems to differentiate between B-52s modified for ALCM carriage and those that are not-must be permanent installations. Salt II, which has not been and may never be ratified, counts ALCM-equipped aircraft as “MIRVed” systems. Hence, the need to provide generically defined identification of ICBMs, SLBM, and aircraft that fall into this category.
Initially the B-52Gs will carry twelve ALCMs externally. This total will be increased to twenty when the aircraft are modified to carry eight additional ALCMs internally. Modification of the G models is to proceed at a rate of four and a half aircraft per month. The first squadron (fourteen aircraft) of modified, ALCM-status in December 1982. Acquisition of the full complement of ALCMs (3,418 miles) won’t be completed until 1987, however.
Upgraded ALCMs Under Consideration
ALCM—whose progenitors include the German V-1 “buzz bomb” of World War II and a series of American World War II inventions—is a 1,500-mile-range subsonic air-breathing missile that resists detection because of optimized radar cross section and by penetrating enemy airspace at extremely low altitude. ALCM, whose official designation is AGM-86B, can fly complicated routs to its target with the aid of a terrain contour matching (TERCOM) guidance system. TERCOM compares surface characteristics encountered during the flight with computerized map data stored in its guidance system altimeter, TERCOM provides pinpoint accuracy for ALCM well within the “lethal zone” of its nuclear warhead. The ALCM procurement program was transferred recently from the Joint Cruise Missile Project Office (JCMPO), operated by the Navy as the executive agency, to ASD. JCMPO continues to furnish Boeing Aerospace (the prime contractor) with the missile’s engine (the F107-MR-101 turbofan design built by William Research Corp.) and the TERCOM (built by McDonnell Douglas Astronautics). Unit cost of the ALCM, according to the Defense Department, is about $1 million.
A senior Defense Department official recently told this writer that planning for improved, second-generation ALCMs is under way. The degree of urgency involved, of course, is a function of how rapidly and effectively the Soviets build up their defenses against the first-generation ALCM. Betting by senior Defense officials at this time is that the Soviets will seek to develop standoff defenses that go after the carriers. The reasoning behind this hypothesis is that the Russians aren’t apt to concentrate on interception of ALCMs in the terminal area—involving either SAMs or fighters—on a one-on-one basis. As one Pentagon Executive put it, the latter “would be extremely difficult since cruise missiles represent such small targets, on the order of about 1,000 times smaller than a B-52 in radar cross section.”
If the Soviets build up their ability to intercept cruise-missile carriers over long distance, it would become necessary to increase the range of ALCMs. A range increase of about 800 miles appears feasible, involving a simple “stretching” of ALCM to provide increased fuel capacity and engine improvements that are being pursued by a number of manufacturers, according to the Defense official. The required lengthening of the missile would not pose any problems for the carrier aircraft.
New Bomber Options
There is a “certain body of opinion that has concluded that penetration will become more and more difficult—as will base escape—and that if you want to hit fixed targets you can do it better with missiles,” according to General Skantze. As a result, most concepts for a new bomber gravitate toward a multipurpose design, including the ability to cope with mobile and other gargets of opportunity under both strategic and tactical warfare conditions. The Air Force, therefore, requested its Scientific Advisory Board to conduct intensive, parametric studies of various design options, “looking across the spectrum from largely penetrator cum ancillary general-purpose capability concepts to the other way around,” General Skantze explained.
The studies were predicted on two “starting points, 1981 and 1985; including intensive industry participation; and focused on new manufacturing technologies in terms of affordability,” the ASD Commander said. The study concluded that if a near-term solution—in the order of the congressional deadline of first aircraft delivery by 1987—is picked logical choice is “a B-1 design incorporating upgrades. These upgrades would include reduced radar cross section, and confine the aircraft to subsonic performance and hence reduced wingsweep,” according to General Skantze. Conversely, the Board estimated that it would take until 1992 before a completely new multirole strategic aircraft could come off the production line. Such a design probably would incorporate variable bypass engines, variable camber wings, reduced radar cross section, advanced radar absorbent materials (RAM), highly miniaturized, high-performance avionics, and composite materials, the SAB concluded.
Operational payoffs of such a long-range combat aircraft (LRCA) would include an unrefueled operating range in the order of at least 6,000 nautical miles, a payload for sensors and weapons in the 20,000- to 100,000-pound range, and provisions to incorporate a rapid-fire laser weapon. Such a design probably would use a supercritical or variable-camber wing, rather than variable sweepwing to achieve rapid base escape and high speeds of treetop levels. If laser weapons can’t be used by LRCA, the likely choices for bomber defense weapons are defensive missiles—possibly AMRAAM derivatives or the Advanced Strategic Air-Launched Missile (ASALM), a multi-Mach weapon with a range of up to 600 nautical miles, General Skantze suggested.
There is some inclination in Congress as well as in USAF to build a mixed force of manned strategic systems involving initially B-1 derivatives and eventually fully optimized, completely new aircraft using at least some “low observable” or “Stealth” technology.