Fighter Wing: A Guided Tour of an Air Force Combat Wing tcml-3
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Beginning with the — C and — D models of the F-16, a new radar, the Westinghouse APG-68, has been installed, with higher reliability (very low false alarm rate, and up to 250 hours' mean time between failure), much greater computer capacity, increased range out to 80nm./146.3km., improved countermeasures against enemy jamming, and a special sea search mode for operation against naval targets. The radar can scan a 120deg arc horizontally and 2, 4, or 6 "bars" in elevation (each bar being about 1.5deg in elevation). These enhancements came at the cost of increased weight — an extra 116 lb./53 kg. The APG-68 offers a lot of choices for a single hard-working pilot, especially in the stress of combat. Fortunately for the pilot, their favorite radar mode presets (along with many other system settings) can be programmed on a mission-planning computer and stored in a DTU cartridge (Data Transfer Unit, much like the DTD on the F-15E Strike Eagle) which snaps into a socket in the cockpit. Designed for continuous upgrading, the APG-68 will eventually provide automatic terrain following, integrated with the aircraft flight control system, a high-resolution synthetic aperture mode (SAR) like the APG-70 on the F-15E, and perhaps even NCTR capabilities. Another possibility is the retrofitting of a radar with an electronically scanned antenna like the APG-77 planned for the F-22 (the present antenna is mechanically scanned in azimuth and elevation by electric motors). All of this translates into a radar as capable as anything flying today, at relatively low cost, volume, and weight.
Because a large number of Fighting Falcons have been sold overseas, an early trial in combat for the little jet was virtually guaranteed. In July 1980, the Israeli Air Force (Hel Avir) received its first F-16s, after an eleven-hour, six-thousand-mile ferry flight from New Hampshire. Within months, the new birds had gone into combat. The highlights of these early actions were the raid on the Osiris nuclear reactor complex near Baghdad in 1981, and the huge air-to-air victory over the Syrian Air Force in what has come to be called the "Bekka Valley Turkey Shoot" over Lebanon. And Pakistani Air Force F-16s scored more than a dozen air-to-air victories against Soviet and Afghan aircraft during the war in Afghanistan.
And then there was "the Storm." During Desert Storm, the performance of the F-16 was something of a disappointment, despite some 13,500 combat sorties that delivered over twenty thousand tons of ordnance. Part of the problem was the rotten weather, for the F-16 is optimized as a clear-weather day fighter. Another part of the problem was the reluctance of the Iraqi Air Force to come out and get killed in air-to-air duels (the F-16 is very capable as an air superiority machine). But the greatest problem was the lack of LANTIRN precision targeting pods. Only seventy-two of the 249 F-16s in the theater had this vital system, and they only had the AAQ-13 navigation pod, and not the AAQ-14 targeting pod. The F-16's bomb delivery software and the training of the pilots had been optimized for low-level attacks, where even the dumbest bombs can be delivered with some accuracy. But the volume of Iraqi ground fire led Coalition air commanders to decree that bombing runs would be made from medium altitude (12,000 to 15,000 feet/3,657.6 to 4,572 meters), an environment where the F-16 was at that time definitely not optimized. Reportedly, software modifications to the weapons delivery system have overcome these shortcomings. However, since that time the F-16 has shined, obtaining six air-to-air kills over Iraqi and Serbian aircraft trying to operate in United Nations mandated no-fly zones, as well as gaining the capabilities inherent to the LANTIRN and ASQ-213 HTS pods.
One criticism of the F-16, compared to its competitors, is its relatively short unrefueled range. The Israelis use six-hundred-gallon external fuel tanks, which extend typical mission range 25 % to 35 %; but the U.S. Air Force has stuck with the standard 370 gallon tanks. Lockheed has recently developed a pair of conformal fuel tanks which hug the upper surface of the fuselage. To cope with the increased weight, the landing gear and brakes are being strengthened. This "enhanced strategic" version will reportedly be able to fly deep penetration missions like the F-15E.
There are other ideas to keep the F-16 alive. In the life cycle of any combat aircraft program, weight growth is almost inevitable, leading to a gradual loss of agility. Considerable research and development has gone into finding ways to compensate for this in the F-16. One experimental variant was the F-16XL, with a greatly enlarged "cranked arrow" delta wing. Another experiment was the Multi-Axis Thrust Vectoring (MATV) engine nozzle, which uses hydraulic actuators to deflect the exhaust up to 17deg in any direction. A very promising future enhancement is an enlarged wing which could be the basis for a third generation of production Vipers.
The ultimate replacement for the F-16 is already evolving, under the acronym JAST, which stands for Joint Advanced Strike Technology. This is likely to be a single-seat, single-engine aircraft that may come into service sometime around 2010, if the Navy, Marines, and Air Force can manage to cooperate enough to impress Congress with the need for a new generation of manned combat aircraft. It will probably incorporate low-observables technologies, but not the super-stealthy features of the F-117, B-2, or F-22. Also, it may wind up using vectored thrust to achieve short takeoff and vertical landing.
ROCKWELL INTERNATIONAL B-1B LANCER
It may seem perverse to describe a bomber as sexy, but when you get up close to the B-1B, the sinuous curves and sculptural form of the airframe radiate an almost erotic energy, looking like smooth flawless skin over warm pulsing muscles rather than aluminum and composite panels riveted to steel and aluminum ribs. Pilots like to say that if a plane looks good, it flies good, and the B-1B proves the point. The plane holds most of the world records for time-to-altitude with heavy payloads, and it has flight characteristics more like a fighter plane than a bomber with twice the weight-carrying capacity of the classic B-52 Stratofortress which it was designed to replace.
Few modern aircraft programs have involved such bitter and protracted political battles as the B-1—or so many radical redesigns — and still made it into squadron service. The B-1 story began with the cancellation of the North American Rockwell XB-70 Valkyrie in 1964. This huge dart-shaped aircraft was designed to fly nuclear strike and reconnaissance missions at Mach 3 above 80,000 feet/24,384 meters. The growing effectiveness of American ICBMs and the Soviet development of surface-to-air missiles (as demonstrated by the downing of the U-2 flown by Francis Gary Powers in 1960) and high-speed, high-altitude interceptors like the MiG-25 threatened, it seemed, to make the manned bomber as obsolete as horse cavalry.
But there was still life in bombers. If there was no safety in high altitude, then a high-speed, low-level penetrator might still get through the thick wall of the Soviet air defense network, but only if a thicket of technical problems could be solved. Low-level means from 50 to 500 feet/15.2 to 152.4 meters above the ground, where the air is dense and you need a lot of power to push it aside. Simple enough over the Nevada salt flats perhaps; but in rough terrain, the mountains and hills are much denser, and you can't push them aside. You have to go up and over them, hugging the contours but avoiding the violent roller-coaster excursions that leave both crew and airframe overstressed and fatigued.
Moreover, fuel considerations make it impossible for an aircraft to fly a low-level dash at supersonic speeds while still carrying a useful payload to a strategically meaningful range, say 7,500 nm./13,716 km. For reasonable fuel economy and fast transit to the enemy border, any new bomber would have to cruise at high subsonic speed above 25,000 feet/7,620 meters, before descending for the run in to the target. One way to achieve this goal is to use "variable geometry" wings. That is, you change the sweep angle of the wings to optimize lift and minimize drag under a wide range of flight conditions. Variable geometry has been successfully implemented on fighter-sized aircraft like the MiG-23 Flogger, F-111, F-14 Tomcat, and Panavia Tornado, but on a big bomber it requires actuators of enormous power and a pivot bearing of immense strength.
In 1970, the Air Force chose Rockwell International (formerly North American Aviation) to develop the "Advanced Manned Strategic Aircraft." It
would be powered by four GE F101 turbofan engines, each rated at 30,000 lb./ 13,600 kg. thrust with afterburner. The first B-1A was rolled out on October 26th, 1974, and the Strategic Air Command (SAC) hoped to procure a total force of 240 of the new bombers to replace the B-52s that had worn themselves out over Vietnam. In those years of runaway inflation, the cost of the plane escalated rapidly, and the complex software-driven avionics system was plagued with the usual development problems inherent in the early systems of this type. Then in 1977, President Jimmy Carter canceled the program in favor of long-range cruise missiles launched from the existing fleet of B-52s. The four completed prototypes were nevertheless retained in service for testing, though one was eventually lost due to a crew error in regulating the aircraft's fuel supply and center of gravity, and another as a result of a collision with a pelican. Bird strikes are a major hazard to low-flying aircraft. Like most tactical aircraft, the B-1 is designed to withstand high-speed collision with a 4 lb./1.8 kg. bird, even on the windscreen transparency. Unfortunately, at 600 knots/1,097.8 kph., the 15 lb./6.8 kg. pelican that hit the Test B-1 was a lethal projectile, taking out a significant part of the hydraulic system and causing the loss of the aircraft.
Meanwhile, by the end of the 1970s, the B-52s weren't getting any younger, and the SAC bomber force, with no follow-on replacement program, was facing obsolescence. As might be imagined, the SAC leadership lobbied hard to get the B-1 program back on track, with lots of support from Rockwell and those who believed in the continued importance and viability of the manned strategic bomber as part of the American nuclear triad (bombers, ICBM, and SLBMs). And in 1981 President Ronald Reagan announced the decision to build one hundred B-1B bombers — externally similar to the B-1A but radically redesigned in many respects. The production of those one hundred aircraft had been at the heart of his presidential campaign promise to rebuild the American military force to face down the Soviet Union in the 1980s. The first production bomber, christened the B-1B Lancer (after a famous pre-World War II interceptor), rolled out of Rockwell's Palmdale, California, plant on September 4th, 1984, with the IOC of the first squadron being achieved on October 1st, 1986.
While it is officially designated the "Lancer," the B-1B's crews call it "the Bone." Currently, B-1B squadrons are based at Dyess AFB, Texas; Ellsworth AFB, South Dakota; and McConnell AFB, Kansas. In addition, the six B-1Bs of Ellsworth's 34th Bomb Squadron, now attached to the 366th Composite Wing, are hopefully scheduled to move to Mountain Home AFB in 1998, when expanded facilities are completed. Finally, two aircraft are permanently based at Edwards AFB, California, for continuing testing and evaluation of new B-1B weapons and systems. The B-1B force did not participate in Desert Storm, since it was then dedicated mainly to the nuclear deterrent role, crew training and software modifications for delivering conventional weapons were incomplete, and it was not really needed in the Gulf.
The place to explore a B-1B is the flight line of Ellsworth AFB near Rapid City, South Dakota, which is the home of the 28th Bombardment Wing, as well as the 34th Bombardment Squadron, which is assigned to the 366th Wing at Mountain Home AFB, Idaho. When you see a B-1B on the flight line at Ellsworth, the first thing you feel is speed. The Bone seems to be moving — and fast — just standing still on the ramp. Then there are the sensuous curves. As you get closer, the details that show the quality of the B-1B's workmanship begin to show, and you begin to notice that the join lines between panels and access doors are almost impossible to see without knowing exactly where to look. Part of the reason for this has to do with the desire of the USAF and Rockwell to make the B-1B as small to enemy radars as possible. While technically not a stealth aircraft, it is considered a "low-observable" airframe, which does give it some penetration capabilities that even small fighters like the F-16 lack. The four afterburning F101 engines are mounted in underwing gondolas, with the two bomb bays located in the fuselage aft of the crew compartment. Except for a pattern of white markings around the in-flight refueling receptacle, B-1s are currently painted the same uniform dark gray as the F-111 and F-15E fleets, with small, low-visibility national markings. In peacetime, B-1 crews have applied some of the most creative nose artwork in the Air Force, but the rampaging animals and well-endowed young ladies would probably be painted over for combat missions, to reduce the visual signature. Moreover, the coming of women to the flight crews of USAF combat aircraft has imposed certain limits of taste upon such decorations, probably to the advantage of all concerned, but to the detriment of a highly cherished tradition of airmen around the world.
A cutaway drawing of the Rockweell International B-1B Lancer.
Jack Ryan Enterprises, Ltd., by Laura Alpher
The crew enters the Bone by climbing a retractable ladder built into the nose wheel well. An interesting feature here is the "alert start" button. Since SAC originally expected to launch under conditions of nuclear attack, a single big red "bang" button on the nose wheel strut can start all four engines and begin alignment of the inertial navigation system, so that the aircraft would be ready to roll as soon as the crew was strapped in. Now that the B-1Bs no longer operate in the nuclear deterrent role, nobody uses the panic start button anymore, and there's time to work through the preflight check-list methodically. You have to be a bit careful going up the ladder, because the aisle is narrow and the headroom is limited. The flight crew consists of a pilot and copilot, who sit side by side in the front, with an offensive avionics operator (who fills the role of bombardier/navigator) and defensive avionics operator in a separate compartment behind them. The backseaters have small side windows, but their attention is dominated by large electronic consoles. The original B-1A design incorporated a complex crew "escape capsule"; the entire cockpit compartment would separate from the aircraft and deploy stabilizing fins and a parachute. But on the B-1B this was replaced by simpler, lighter, and more reliable ACES II ejection seats. Blow-out panels above each crew position are triggered by the ejection mechanism, which has a surprisingly good record for crew survival in emergencies. The in-flight refueling receptacle is built into the nose, just forward of the windshield; flight crews with B-52 experience find this a bit disorienting at first.
The controls, while not quite as advanced as those on the F-15E or F-16C, are quite easy to use, and very functional. You sit in the pilot's seat, with the fighter-style control stick fitting in a nice, neutral position that is designed to reduce crew fatigue. While there is no HUD, the mission data is easily read from several MFDs located on the instrument panels. The throttle quadrant is located on a pedestal between the pilot and copilot positions, with other common controls like navigation and flight management systems being positioned there for easy access from either position. Engine, fuel, and other indicators are of the "strip" type, much like an old-style mercury thermometer. These visual readouts make it easy to see if an engine or some other system is operating within "green" (safe) parameters or in a "red" (danger) situation. There is also a small panel of enunciators, which show system status and warning lights for things like engine fires or low hydraulic pressure.
B-1s prefer to operate as lone wolves. Any escorting fighter that is not stealthy is likely to increase the risk of enemy detection. In low-level penetration missions, when the autopilot is coupled to the TFR mode of the APQ- 164, speed is life. At 500 feet/152.4 meters altitude, the B-1's cruising speed is about 550 knots/1,006 kph., and at full afterburner it can be cranked up to just a hair over the speed of sound. Maximum takeoff weight is 477,000 lb./ 216,365 kg., with a maximum altitude of over 50,000 feet/15,240 meters.
No fighter in the world can overtake a B-1B operating at low altitudes. Over rough terrain, any fighter pilot who tries to stay on the B-1's tail is likely to have a highly detrimental intersection with the ground. In addition to the APQ-164's TFR radar mode, what makes this possible is a pair of small downward-slanted vanes on the nose, just forward of the cockpit. (From some angles, they make the plane look like a catfish.) Everything on an aircraft gets an
acronym, and these little fins are part of the SMCS: Structural Mode Control System. Flying at low altitude means an aircraft is going to encounter turbulence even in good weather. This can make the aircraft dangerously hard to control, fatigues the crew, and causes flexing of the airframe that drastically shortens its service life. To reduce this problem, a set of accelerometers mounted in the aircraft sense the turbulence, and a computer rapidly moves the fins to compensate. The effect is to limit the vertical accelerations felt by the crew to no more than three Gs.