VI - STEALTH AIRCRAFT: EAGLES AMONG SPARROWS?



The new generation of American combat aircraft, including the F-117A, YF-22, the A-12 and the B-2, are all characterized by stealth features unmatched by the aircraft of other countries. While these new systems may provide some operational advantages, they have not rendered all other aircraft obsolete. Stealth is by not means a prerequisite for delivery ordnance on target, since as previously discussed, the performance of air defense systems against more conventional attack aircraft still leaves much to be desired. Nor should stealth be regarded as the final move in the game of electronic countermeasures, given the variety of design and operational constraints imposed by stealth. Finally, all the American stealth projects face serious budget problems, and their future is far from assured.



STEALTH TECHNOLOGY

Stealth has become the magic word in contemporary weapon systems. Contemporary work on stealth has its roots in long-standing efforts to reduce the visibility of military aircraft through camouflage paint schemes. However, as electronic sensors have replaced the eyes of pilots as the primary means of tracking other aircraft, more intricate means of defense were needed.

Often thought of simply as the use of special materials to render aircraft invisible to radar, stealth is actually a complex design philosophy to reduce the ability of an opponent's sensors to detect, track and attack an aircraft (or other platforms such as warships). Since a variety of sensors would be used in this process, design of a stealth vehicle requires careful trade-offs among different techniques. The great secrecy surrounding stealth programs is designed not simply to protect a particular stealth technology, as it is to protect the choice and mix of techniques that have been used in a specific system. (1)

A variety of technologies are may be combined in order to make itself "invisible" to radar. These technologies include a smooth surface, "flying wing" design, radar absorbent materials (RAM), engines hidden in the body of the airplane, and electronic countermeasures (ECM). Each of these features contribute to the attempt fool enemy air defense systems. The planes low radar cross section (RCS) reduces the range at which ground-based and air-based radars can detect the aircraft. The RAM absorbs most of a radar's signal, and the aircraft's wing-shaped and rounded design redirects much of the remaining power away from the radar source. Engines are buried in the fuselage with air intake and exhaust ducts placed on the top of the aircraft in order to reduce the heat trail, and hide the jet engine's compressor blades from radar detection. ECM is a last resort attempt to confuse the radar operator through jamming and ghost imaging.



The benefits of stealth technology is inherently obvious. Especially since, 70 percent of Soviet-style air defense systems use radar detection and tracking.(2) However, as the next section on limitations will illustrate, the other elements of air defense detection and tracking; infrared (IR), electro-optical (EO) and visual, also need to be circumvented if an aircraft is to be truly "stealthy."



LIMITATIONS

There is no one optimum stealth design, but rather each mission requirement generates an appropriate mix of techniques. Implementation of stealth is not without penalties. Some of the materials used require special and costly maintenance. The maneuverability of an aircraft can be compromised by the introduction of stealth design features. As was the case with the F-117A, each B-2 bomber will have its own covered maintenance facility, since the B-2's low observable features require frequent performance of structural and maintenance activities.(3)

Stealth requires not only design compromises, it also imposes operational compromises. Sensors to locate targets pose a particular problem for stealth aircraft. The large radars used by conventional aircraft would obviously compromise the position of a stealth aircraft. Air-to-air combat would rely on passive detection of transmissions by hostile aircraft, as well as infrared tracking. However, these techniques are of marginal effectiveness against other stealth aircraft, explaining the limited application of stealth to the Advanced Tactical Fighter.

Aircraft for attacking targets on the ground face a similar problem. FLIR can be used for precise aiming at targets whose general location is known, but they are poorly suited for searching for targets over a wide area. A radar on the aircraft to scan for potential targets would compromise its position. In order to locate targets, stealth aircraft may rely on an airborne laser radar, although such a sensor may prove of limited utility in poor weather. A more promising approach would be to use data from reconnaissance satellites, either transmitted directly from the satellite or relayed through communications satellites from processing centers in the United States.

There are limits to the utility of stealth techniques. Since the radar cross-section of an aircraft depends on the angle from which it is viewed, an aircraft will typically have a much smaller RCS when viewed from the front or rear than when viewed from the side or from above. In general stealth aircraft are designed to minimize their frontal RCS. But it is not possible to contour the surface of an aircraft to reduce the RCS equally in all directions, and reductions in the frontal RCS may lead to a larger RCS from above. Thus while a stealth aircraft may be difficult to track when it is flying toward a ground-based radar or another aircraft at the same altitude, a high-altitude airborne radar or a space-based radar may have an easier time tracking it.

Another limitation of stealth aircraft is their vulnerability to detection by bi-static radars. The contouring of a stealth aircraft is designed to avoid reflecting a radar signal directly back in the direction of the radar transmitter. But the transmitter and receiver of a bi-static radar are in separate locations -- indeed, a single transmitter may be used by radar receivers scattered over a wide area. This greatly increases the odds that at least one of these receivers will pickup a reflected signal. The prospects for detection of stealth aircraft by bi-static radar are further improved if the radar transmitter is space-based, and thus viewing the aircraft from above, the direction of its largest radar cross section.

Several analysts claim stealth aircraft such as the ATF will be vulnerable to detection by infrared search and track systems (IRST). The natural heating of an aircraft's surface makes it visible to this type of system. The faster and aircraft flies, the warmer it gets, and thus, the easier to detect through infrared means. One expert asserts "if an aircraft deviates from its surroundings by only one degree centigrade, you will be able to detect it at militarily useful ranges."(4) In fact, both the Russian MiG-29 and Su-27 carry IRST devices, which indicates that the Russians have long targeted this as a potential stealth weakness.(5)

Stealth aircraft are even more vulnerable to multiple sensors used in tandem. By using an IRST to track the target and a Ladar (laser radar), or a narrow beam, high-power radar to paint the target superior data is provided.(6)

The most basic potential limitation of stealth, is its vulnerability to visual detection. Since the ATF is 25-30 percent larger than the F-15 and 40 percent larger than the F-18, for example, it will be much easier to detect visually from ranges on the order of 10 miles.(7) When one considers that stealth characteristics will drastically reduce the effectiveness of several types of guided air-to-air missiles, fighter engagements will probably move back to the visual range arena. In this context, the cumbersome F-22 would be at a distinct disadvantage.(8)

Another potential "limitation" of stealth technology has little to do with its capabilities. Rather, some question the effect the pursuit of such hi tech aircraft will have on the US aerospace industry as a whole. These aircraft would not be available for foreign export until well into the next century. During that time, competitors such as the Gripen, Rafale and EFA will be peddled aggressively by European exporters. One analyst estimated that US foreign sales saved the Pentagon "about $2.8 billion through surcharges to recover part of their development costs and perhaps another $4 billion through the learning curve effect of higher production runs."(9) Thus, America's stealth success could actually backfire, on its larger aerospace industry by causing it to forfeit sales to a new generation of top-of-the-line, although less formidable, European fighter aircraft.(10)



Programs

F-117A - Development of stealth aircraft began in the early 1970s, with the Experimental Stealth Tactical (XST), code-named "Have Blue." This project resulted in the Lockheed F-117A, with 20 of these aircraft ordered from Lockheed by the Air Force in 1981, and a total of 59 aircraft were produced. The F-117A first flew in 1983 and entered service at Nellis Air Force Base in Nevada in 1983. The original F-117A program envisioned over 100 aircraft, but soaring costs (each aircraft costs over $100 million), performance problems (several of the aircraft have crashed in training flights),(11) limited payload (the aircraft can carry only two 900 Kg laser guided bombs internally)(12), and the lack of a clearly defined mission(13) all contributed to the curtailment of the program.(14) Although the F-117A exhibits breakthrough low-observable characteristics, it was not built from scratch. Designers modified F-16 flight controls and F-18 engines. Lockheed officials say that using and improving on existing technology, rather than re-inventing the wheel, allowed them to make the F-117 at half the cost and in half the time of equivalent aircraft.(15)

The F-177A first saw combat in the American intervention in Panama in December 1989, when two of the aircraft were used to attack an airfield, but this mission was marred by pilot error which caused one of the aircraft's bombs to land far from the intended target.(16) The F-117A performed well in Desert Storm, which may be the primary reason that the aircraft's production line, once slated for closure, has recently been revived.(17)



ATF - YF-22 The Advanced Tactical Fighter, which will enter Air Force service in the mid-1990's, is designed primarily to carry missiles such as the AMRAAM for air superiority operations. The ATF will combine supersonic cruise capability with enhanced maneuverability. The ATF design by Lockheed, General Dynamics and Boeing was selected in April 1991 over the YF-23 of Northrop and McDonnell Douglas. Although less futuristic and perhaps less capable than the Northrop design, Air Force officials said risk was key to their decision to buy the F-22. Lockheed was judged more likely to be able to accomplish what it proposed.(18)

The two competitors embraced different philosophies concerning the future air battle. Lockheed designed an aircraft that would be superior in both the visual and beyond visual range battles. It maintained that in the future there will always be occasions when aircraft get within visual range of each other. In those scenarios, stealth offers no advantages. Thus, the F-22 incorporates some stealth features such as internal weapons carriage,(19) but the stealth characteristics of the airframe configuration have been compromised by aerodynamic considerations required to execute the close-in dogfight. (20) Northrop, by contrast, prophesied that close-in air battles were unlikely in the future, and optimized stealth and maximum speed at the expense of agility.

The F-22's advertized capabilities sound impressive. It will be more agile than current fighters with higher climb rates and turning acceleration. According to some advocates, the fighter's ability to execute sharp turns at supersonic speeds will revolutionize next century's dog fight tactics. Air to air tactics would also be radicalized by the ATF's ability to detect, target and destroy other aircraft well before they themselves were discovered. The ATF will employ "supercruise," which will enable it to fly at a speed of at least Mach 1.56 without afterburners, greatly reducing IR signature and saving fuel. Its speed/altitude operating envelope without afterburners is estimated to be greater than the F-15C's with afterburners. The F-22's radar signature is estimated at 1,000 times smaller than the F-15s.(21) The F-22 is predicted to have a 25 percent greater range than the current F-15C.(22) The YF-22 will employ thrust vectoring which will give it a substantial maneuverability advantage over other aircraft both at the lowest and highest speeds. Seventy five percent of the ATF's cost will be eaten up by the aircraft's most technical components; the avionics, integration, manufacturing and materials technologies.(23)

The ATF's avionics reportedly have the throughput capacity of seven Cray computers.(24) The "brains" will be provided by a Hughes Aircraft Common Integrated Processor, which has been described as an ultrafast central computer made up of common modules. The radar will be of the electronically scanning, active phased array variety. The Integrated Communications Navigation Identification Avionics (ICNIA) will consolidate into a single suite the functions usually performed by several processors, transmitters and receivers. The Integrated Electronic Warfare System (INEWS) will also combine functions currently performed by several systems into a single unit. It will handle electronic warning and countermeasures tasks.(25)

While Defense Secretary Cheney's Major Aircraft Review did not cut the Air Force goal of buying 750 aircraft, it did defer production by two years, and reduce the maximum annual build rate from 72 per year to 48 per year.(26) This reduction in procurement is partially responsible for the 23 percent increase over the ATF's original $79.5 billion price tag.(27) Development is estimated at $18 billion and production $80 billion. Another ramification of the ATF's development costs is that the Air Force will stop production of F-16s and F-15s (arguably the best fighters in the world in their respective classes) long before originally planned.(28) Pentagon officials say the ATF is required because by the early 2000s foreign countries may close the gap in avionics and pilot training that currently makes the F-15 superior to other "aerodynamically competitive" aircraft.(29)

In light of diminishing governments funds and the almost non-existent threat from the former Soviet Union, a broad range of analysts and policy makers are wondering if spending $95 billion on 650 ATFs(30) is a good idea. While the F-22's capabilities are indeed revolutionary, the requirement for such capabilities is unclear. Upgrading the aircraft which were so effective in Desert Storm, or pursuing agreements with other advanced countries to mutually postpone developing new fighter aircraft for a decade may be better guarantors of US national security than developing such an expensive weapon. Pentagon officials claim that F-15s could be upgraded to beyond rough parity with top of the line Russian fighters, "but not to the revolutionary extent of the ATF."(31) considering the Russians are busy trying to keep from fragmenting like a broken mosaic, does the United States really need to improve on today's MiGs to a "revolutionary extent"?

NATF

Boeing, General Dynamics and Lockheed are trying to interest the US Navy in a carrier-based variant of the ATF, dubbed the NATF (Navy ATF) as a candidate in the AX competition. The NATF was canceled as a program in the Navy's FY'92 budget submission, but the A-X may breathe new life into the program.

The manufacturers claim the NATF has a number of advantages over the other competitors. The Navy's stealth requirement, for example, would prove easier for the NATF to satisfy than upgraded F-14s, A-6s and F/A-18s. The NATF's weapon bay is almost as large as the A-12s, allowing most if not all radar reflecting armaments to be carried internally.(32) Price is another factor. Although the NATF is projected to be a much larger aircraft than the ATF, and carry a larger bomb load, there would still remain a great deal of commonality between the programs. Enough commonality in avionics, armament, and subsystems, say Lockheed officials, to save the NATF program $11 billion.(33) In current and future budget crunches, each service may be forced to purchase each other's aircraft. The NATF may be Lockheed's only opportunity to manufacture a strike ATF, as Air Force Officials have expressed no interest in a two-seat F-22 follow on.(34)



ATA - A-12 - On 7 January 1991, Secretary of Defense Richard Cheney canceled the Navy's A-12 Avenger Advanced Technology Aircraft (ATA) slated to replace current A-6s on aircraft carriers in the mid-1990's. It was the largest contract termination in the DoD's history. By one estimate the A-12 had become so expensive that it would have consumed up 70 percent of the Navy's aircraft budget within three years.(35) The Navy originally planned to buy 620 of the McDonnell Douglas/General Dynamics aircraft, and the Air Force at one point considered buying 400, at an average cost that was estimated at close to $100 million each. The A-12 was designed to fly faster and further than the A-6E, and carry a large bomb-load, in internal bomb-bays to reduce drag and maintain a low radar cross-section.(36) As with the ATF, the A-12 was expected to have greater reliability than current aircraft (double that of the A-6E), and require half the maintenance manhours.

The A-12 proved to be the most troubled of the new American stealth aircraft in large part because of problems found in the extensive use of composites in the aircraft's structure. These composites did not result in anticipated weight savings, and some structural elements had to be replaced with heavier metal components. The weight of the aircraft exceeded 30 tons, 30% over design specification, and close to the limits that can be accommodated on aircraft carriers.(37) The program experienced problems with its complex Inverse Synthetic Aperture Radar system,(38) as well as delays in its advanced avionics components.(39)

The full scope of these problems were not appreciated at the time of Defense Secretary Cheney's Major Aircraft Review, which slowed the production rate and dropped 238 Marine Corps aircraft from the original total Navy buy of 858 aircraft. Cheney also decided to delay for over 5 years the Air Force buy (from 1992 to 1998), which was decoupled from the Navy project.(40) Subsequently, the A-12 contractors revealed that the project was faced with serious engineering problems and a $2 billion cost overrun, which would delay the first flight by over a year, to the fall of 1991.(41)

At first blush, the A-12's performance capabilities would have been in roughly the same class as existing aircraft.


		Payload		Range		Max Weight	Max Speed	Cost*


A-12**		16,000lb	1,200mi		58,000lb	Mach  .9	$105 

A-6E		 6,000lb	1,011mi		58,000lb	Mach  .9	n/a

F/A-18D		 4,000lb	  575mi		56,000lb	Mach 1.8	$40

F-14D		 8,000lb	2,000mi		74,350lb	Mach 1.88	$75


* Cost in $ millions; unit procurement(42)

**A-12 figures estimates.(43)





The A-12's key improvement over existing aircraft, not inherently obvious when comparing specifications, was stealth. While today's radar can detect existing naval aircraft at a range of 50 miles, the A-12 was designed to remain undetected until approximately 10 miles distant. This would result in significant operational and survival benefits for the A-12 since defenders would have little opportunity to engage the aircraft once detected so close to the target. The A-12's reduced radar cross section would have been derived, in part, from carrying its ordnance internally. While the top speed of the more visible F/A-18 and A-6 would be significantly reduced by the drag induced by external weapons carriage, the internal weapons bay on the A-12 would provide no impediment to speed.(44)

When the A-12's problems became apparent, renewed interest in alternatives to the A-12 surfaced. (45) The three programs considered were an upgraded A-6G, F/A-18, and "Advanced Tomcat 21" (ATC-21) F-14D. While the A-6 was really not a player, the other entrants had competing advantages and disadvantages. The upgraded F/A-18, for example, would be cheaper and more amenable to low observables than the F-14.(46) Others point out, however, that it would have to add the all-weather capability that the A-6 successor would require.(47) The ATC-21, proponents said, would have greater range and payload than the F/A-18.(48) Upgrading existing aircraft, however, would be extremely expensive.



AX - Because it is doubtful that upgraded existing aircraft will be able to fulfill all of the A-12s requirements, Navy officials decided to get fresh bids for a new A-12.(49) The Navy estimates the AX to cost $150 per unit as opposed to the A-12's $165 price tag.(50) In FY 1992, the AX program will receive over $100 million.(51) To facilitate this program's implementation, the Navy reportedly quizzed the Air Force on how it resurrected the B-1 after President Carter's cancellation.(52)

The A-X's capabilities have been slightly scaled back from those of the A-12. The A-X could be termed "A-12 lite" as its range, payload, and stealth requirements will all be more modest than its predecessor's.(53) The Navy has emphasized the strike role at the expense of the air-to-air mission in the new program, rather than trying to "cover all the bases" and produce an aircraft that could perform numerous roles. This ambition proved to be the A-12's undoing.

The AX's initial operating capability (IOC) is planed to be between 2000 and 2004, four to eight years later than the A-12's 1996 IOC.(54)

The program has engendered one of the most elaborate and bizarre contractor mating dances in history. Five teams are competing for the prime contractor slot. Team one is comprised of McDonnell Douglas and the LTV Corporation. Team two is General Dynamics and McDonnell Douglas. Team three is made up of Boeing, Lockheed, and General Dynamics. Team four is Grumman, Boeing, and Lockheed. Northrop had a difficult time filling its dance card, apparently because of its bad public image, but it eventually seduced General Dynamics to enter the contest with its third entrant.(55) Thus, of the seven teams competing, it appears that four have developed advanced cases of schizophrenia. McDonnell Douglas, General Dynamics, Lockheed and Boeing have be employing at least two separate teams of engineers working at separate locations who won't be allowed to exchange strategy or data.(56)

While the mating process may seem original, some of the designs are not. General Dynamics and McDonnell Douglas will rehash their A-12 design and Boeing, General Dynamics and Lockheed will offer a version of their F-22 ATF. Grumman originally tried to market upgrades of its F-14 Tomcat as an A-12 replacement. The Navy rejected the Tomcat primarily because of its lack of stealth, but the Grumman, Boeing, Lockheed team will surely draw from Grumman's F-14 and naval aviation experience.(57) Even if the macro-design for the AX is new, it is likely that the aircraft will borrow from other programs for subcomponents. The A-12 cancellation set back the Navy's schedule, and it is looking at the F-22's avionics package for possible integration. TRW is investigating how avionics being developed for the F-22 could be used on the AX. Monetary savings is reportedly a prime motivation.(58)

In addition to the A-X's elaborate contractor mating dance, the project's contractor/Navy contractual relationship will be unusual as well. It will be the first aircraft in a decade to be built on a "cost plus" -- which allows the Pentagon to reimburse contractors for costs incurred over the agreed ceiling -- rather than a "fixed price" basis.(59) Industry officials blamed the A-12's fixed price contract for cramping their flexibility in addressing and solving problems as they arose.(60)



ATB - B-2 - The Stealth Bomber project was first announced by the Carter Administration in the heat of the 1980 Presidential campaign, in response to Republican criticism of the decision to cancel the B-1A bomber. Since its unveiling in November 1988, the B-2 has been the focus of mounting criticism of the inexorably growing cost of the project, the regularity with which its schedule has been delayed, and doubts about mission requirements.

The B-2 will be the most expensive aircraft ever procured, and by some estimates each bomber will literally cost its weight in gold. The General Accounting Office estimated that the cost of the 132 aircraft program in then-year dollars would total $68.8 billion, based on a $36.6 billion cost in constant FY81 dollars.(61) By mid-1988 the cost estimate for 132 aircraft had grown to $43 billion (in constant 1981 dollars).(62) In the Spring of 1990 Secretary Cheney's decided to reduce the buy from 132 aircraft to 75, with a budget in then-year dollars of $61 billion.(63) Based on the costs required to bring the B-1B up to its intended performance (an additional $8 billion over the original $20 billion price) the eventual cost of the more technologically challenging B-2 could exceed $1 billion each.

Two missions for the B-2 emerged from the veil of secrecy. Some advocates argued that the B-2 is needed to offset improvements in Soviet air defenses, and that the exertions the Soviets would make to augment their air defenses to counter the B-2 will inhibit their efforts in strategic offensive and conventional forces. Others argue that the B-2 is needed in order to attack Soviet mobile missiles such as the SS-24 and SS-25. But given the high cost of the project and competing budget priorities, neither of these rationales has proved particularly compelling to the Congress. Secretary Cheney's decision to reduce scope of the program proved a watershed. Recently, House and Senate conferees agreed to spend only $1.8 billion in 1992 on the B-2. Nothing more can be spent on the aircraft without the approval of the full House, which has been consistently opposed to the program. While supporters of the Stealth Bomber say the aircraft's future is unclear, the $1.8 billion figure was a distinct setback. Critics claim that the agreement literally kills the program.(64)



Non - US Programs

Great Britain has expressed interest in developing its own low-observable aircraft. The US Air Force has clearly indicated its interest in selling the F-117 to the United States' closest ally. It is more likely, however, that London will acquire certain stealth technologies that it can use in its down programs, than buy the finished product.(65) Britain plans to begin work on a stealth aircraft in the next five years,(66) and have a functioning technology demonstrator by the end of the 1990s.(67) The RAF says it will develop an upgraded Tornado that will be akin to the US Navy's AX strike aircraft.(68) The RAF has been conducting radar absorbent material (RAM) experiments on Tornados since at least November 1990.(69)

One phenomenon that worries US defense officials is the technology lag between the time the United States fields a particular system, and the time its adversaries do. For example, while the United States' top line fighter was introduced in 1975, the Soviet's top fighter, the MiG-29's initial operating capability (IOC) was 11 years later in 1986. Thus, "their" best aircraft is based on technology 11 years more modern than "ours." Secretary of Defense Cheney has recently voiced concern that this may apply to the fielding of stealth technology, and that 11 years after the F-22s IOC, for example, we will be facing a brand new Russian stealth fighter.(70)


References

1. Most of the technical discussion in this section is based on the definitive work by the leading stealth authority Bill Sweetman, Stealth Aircraft (Motorbooks, Osceola, WI, 1986.

2. Brinkley, Randolph, "Future US Fighters Are at a Cost/Technology Crossroad," Armed Forces Journal International, January 1991, p.49.

3. "AF Plans Individual Covered Parking Spaces for B-2 Bombers," Aerospace Daily, 8 March 1988, pp 358-359.

4. Tusa, Francis, "Europeans suffer stealth sticker shock syndrome," Armed Forces Journal International, February 1991, p.24.

5. "ATF Might Be Tracked By Skin Friction Infrared Signature," Aerospace Daily, 26 November 1990, p.323.

6. Tusa, Francis, "Europeans suffer stealth sticker shock syndrome," Armed Forces Journal International, February 1991, p.24.

7. Brinkley, Randolph, "Future US Fighters Are at a Cost/Technology Crossroad," Armed Forces Journal International, January 1991, p.49.

8. Brinkley, Randolph, "Future US Fighters Are at a Cost/Technology Crossroad," Armed Forces Journal International, January 1991, p.49.

9. Schemmer, Benjamin, "Will Stealth Backfire," Armed Forces Journal International, January 1991, p.44.

10. Schemmer, Benjamin, "Will Stealth Backfire," Armed Forces Journal International, January 1991, p.44.

11. Evans, David, "The Stealth May Be Invisible, But Its Deficiencies Aren't" Chicago Tribune, 18 November 1988, page 12.

12. "Stealth -- The Next Step," Flight International, 18 April 1990, page 24.

13. Reed, Fred, "Stealth Fighter Remains a Mystery," Air Force Times, 5 December 1988, page 78.

14. Wilson, George, "Secrecy's Veil Lifted From Stealth Jet," The Washington Post, 11 November 1988, page A3.

15. Wartzman, Rick, "Designer of Stealth Fighter Says US Runs Risk of Losing Technological Edge," The Wall Street Journal, 4 February 1991, p.A7.

16. Gordon, Michael, "Stealth Jet's First Mission Was Marred, Pentagon Says," The New York Times, 4 April 1990.

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18. Bond, David, "Risk, Cost Sway Airframe, Engine Choices for ATF," Aviation Week & Space Technology, 29 April 1991, p.20.

19. Dudney, Robert, "The ATF and Its Friends," Air Force Magazine, January 1989, page 46-53.

20. "Analysts Fear YF-22 Not As Stealthy as YF-23," Defense Daily, 4 September 1990, page 357.

21. Gellman, Barton, "Zeroing In on America's 21st-Century Fighter Jet," The Washington Post, 21 April 1991, p.A1.

22. Schemmer, Benjamin, "Will Stealth Backfire," Armed Forces Journal International, January 1991, p.44.

23. "Lockheed: Thrust Vectoring is Big Plus at Lowest, Highest Speeds," Aerospace Technology, 6 February 1991, p.216.

24. Wartzman, Rick, "Designer of Stealth Fighter Says US Runs Risk of Losing Technological Edge," The Wall Street Journal, 4 February 1991, p.A7.

25. Goodman, Glenn, "ATF Balances Stealth, Supercruise, Agility, Avionics," Armed Forces Journal International, June 1991, p.78.

26. "Cheney Cuts $34.8 Billion From Major Aircraft Through Fiscal 1997," Aerospace Daily, 27 April 1990, page 159-163.

27. "GAO estimates ATF program costs have increased another $1.7 billion," Inside the Pentagon, 7 February 1991, p.13.

28. Gellman, Barton, "Zeroing In on America's 21st-Century Fighter Jet," The Washington Post, 21 April 1991, p.A1.

29. Bond, David, "Risk, Cost Sway Airframe, Engine Choices for ATF," Aviation Week & Space Technology, 29 April 1991, p.20.

30. Gelb, Leslie, "F-22 = $95 Billion," The New York Times, 22 May 1991.

31. Canan, James, "The Future Is Stealth," Air Force Magazine, January 1991, p.14.

32. Starr Barbara, "Avenger: counting the costs of program cancellation," Jane's Defence Weekly, 19 January 1991, p.79

33. Schemmer, Benjamin, "Northrop, Lockheed, and Engine Firms Sweat Out April 30th ATF Decisions," Armed Forces Journal International, February 1991, p.14.

34. "Air Force: No Strike F-22 Unless it's A-X; Cost is main DAB issue," Aerospace Daily, 11 June 1991, p.421.

35. Schemmer, Benjamin, "Will Stealth Backfire," Armed Forces Journal International, January 1991, p.44.

36. "Iraq's Invasion of Kuwait Illustrates need for A-12 Avenger, Navy Says," Inside the Pentagon, 23 August 1990, page 18.

37. 'A-12 Weight Creep Continues; Composites Disappointing," Aerospace Daily, 24 August 1990, page 319.

38. "Norden Says GD Admits it Can't Prove A-12 Subcontract Default," Aerospace Daily, 30 August 1989, page 369-370.

39. "First 200 ATAs to Fly With A-6 Avionics, Lawmaker Says," Navy News & Undersea Technology, 14 March 1988, page 8.

40. "Major Aircraft Review," Inside the Pentagon, 27 April 1990, page 7-8.

41. "A-12 Makers Are Running Out of Cash," Defense Week, 1 June 1990, page 1, 13.

42. "Morrocco, John, "Senior Navy Officials Doubt AX Adaptable to Multirole Capability," Aviation Week & Space Technology, 13 May 1991, p.25.

43. Wartzman, Rick, "Cheney's Bomb Rattles Aerospace World," The Wall Street Journal, 9 January 1991, p. A2.

44. Wartzman, Rick, "Cheney's Bomb Rattles Aerospace World," The Wall Street Journal, 9 January 1991, p.A2.

45. Holzer, Robert, "A-12 Woes Prompt New Look at Intruder," Defense News, 23 July 1990, page 1, 32.

46. Morrocco, John, "Navy to Cut Carrier, Upgrade F/A-18; Cheney threatens to terminate A-12," Aviation Week & Space Technology, 24 December 1990, p.78.

47. "Navy Expected To Ask Congress For More Rewinged A-6 Aircraft," Defense Daily, 9 January 1991, p.33.

48. "Navair has A-12 alternative study in Hip Pocket," Defense Daily, 4 January 1991, p.10.

49. Wartzman, Rick, "Cheney's Bomb Rattles Aerospace World," The Wall Street Journal, 9 January 1991, p.A2.

50. "Development, Production Cost of 575 A-X Planes Put At $86.3 billion, Aerospace Daily, 15 May 1991, p.261.

51. "AX funded for over $100 million in FY'92," Defense Daily, 4 February 1991, p.169.

52. "Navy To Release RFI For A-12 Replacement Within A Month," Aerospace Daily, 29 January 1991, p.153.

53. "Future of Naval Aviation Begins Wigh Issuance of A-X RFP," Inside The Navy, 2 September 1991, p.8.

54. "AX To Be Long-Term A-12 Replacement," Defense Daily, 22 January 1991, p.99.

55. Holzer, Robert, "Northrop, GD Team on AX," Defense News, 28 October 1991.

56. Pearlstein, Steven, "Strange Bedfellows Emerge to Chase AX Bid," The Washington Post, 21 July 1991, p.H1.

57. "Grumman Pushing F-14 Strike Variants In Wake Of A-12 Cancellation," Defense Daily, 11 January 1991, p.49

58. Holzer, Robert, "AX May Share F-22 Avionics," Defense News, 28 October 1991, p.8.

59. "A Sigh Of Relief On Wall Street: Firms Vying For AX Plane Don't Risk Exposure," Defense Week, 22 July 1991, p.6.

60. Brown, David, "General Dynamics Pursuing AX Efforts As Member of Two Development Teams," Aviation Week & Space Technology, 17 June 1991, p.191.

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62. George Wilson, "Cost of Stealth Bombers Soars to $450 million," The Washington Post, 15 May 1988, page 1.

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