The unique characteristics of the fly-by-wire flight-control system allowed the General Dynamics engineers to do a number of new things to the cockpit of the F-16. The ACES II ejection seat, for example, is reclined at an angle of 30°, since this helps to reduce the frontal cross section of the aircraft, which cuts drag and is also more comfortable, especially when pulling high-G maneuvers. The single-piece bubble canopy provides better all-around visibility than any modern fighter aircraft in the world. Remember that most planes shot down in combat never see their opponent sneaking up from behind or below. The lack of normal hydraulic runs means that the control stick can be mounted on the right side of the cockpit, instead of the usual position between the pilot’s legs, which eases the strain on the pilot during maneuvers. Mounted on the right armrest, the “side stick” controller is a force-sensing device which requires only light pressure to execute large and rapid maneuvers.
The cockpit of a Lockheed Martin Block 50/52 F-16C Fighting Falco. Just above the pilot’s bare knees are the two Multi-Function Displays (MFDs), with the Heads-Up Display (HUD) mounted on top of the Data Entry Panel. Lockheed Martin
The throttle column is on the left armrest, and both it and the side stick are studded with the same kind of HOTAS radar, weapon, and communications switches as the F-15, and are optimized for operations in high-G maneuvers. In front of the pilot is a small but busy control panel, with the HUD mounted on top, the display for the RWR to its left, and the IDM display (called a Data Entry Display) on the right. Below this is a center pedestal that runs between the pilot’s legs. It contains most of the analog flight instruments (artificial horizon, airspeed indicator, etc.), the data keypad (called an Integrated Control Panel), and a pair of MFDs, one on either side of the pedestal.
You can hang a lot of weaponry—up to ten tons of it—on an F-16, if you’re willing to pay the costs. These include increased drag, which translates into decreased range, endurance, speed, and agility. However, even when heavily loaded, an F-16 is a dangerous opponent, as a number of Iraqi and Serbian pilots have found out the hard way. On the wing tips are launch rails for AIM-9 Sidewinder AAM or AIM-120 AMRAAM. About 270 F-16s assigned to Air Defense units of the Air National Guard also have the software and radar modifications needed to launch the AIM-7 Sparrow, though this older AAM is rapidly being phased out of service in favor of the newer AIM-120. Under each wing are three hard points where pylons can be installed to carry additional missiles, bombs, pods, or fuel tanks.
Another station under the centerline of the fuselage usually carries a fuel tank, but can also be fitted with an electronic jamming pod (the ALQ-131 or ALQ-184) or (in the future) a reconnaissance pod. All F-16s have an M61 Vulcan 20mm cannon located inside the port strake, with over five hundred rounds of ammunition in a drum magazine just behind the cockpit. The muzzle exhaust of the gun is well clear of the engine air intake to avoid any ingestion of gun gases.
The F-16’s sharply pointed nose provides limited space for a radar antenna, so the designers of the Westinghouse APG-66 radar had to use cleverness rather than brute force to get the performance that was required. This included the ability to launch air-to-air missiles, aim the gun, drop bombs, and deliver air-to-ground missiles. When it was finished, the entire APG-66 installation weighed only 260 lb./115 kg., and it was one of the first airborne radars to use a digital signal processor, translating the stream of analog data from the X-band pulse-Doppler receiver, filtering out clutter, and displaying simplified symbology in the pilot’s HUD or one of the display panels. In the “look down” mode, the new radar could scan the ground 23 to 35 nm./45.7 to 64 km. ahead, while in “look up” mode it could search the air as far as 29 to 46 nm./53 to 84.1 km.; the higher figures represent performance under ideal conditions, while the lower figures are worst-case maximums. The solid reliability and modular design of this radar has allowed it to be modified for installation on a wide variety of aircraft and other platforms, including the Rockwell B-1B bomber and the tethered “aerostat” balloons that scan the skies of the U.S. southern borders for drug-smuggling aircraft.
Even as the early-model Fighting Falcons were going into general service, improvements were already being contemplated for the F-16. These became the F-16C and -D (the two-seat trainer), which had a number of sub-variants or Blocks which first came into series production in 1985. The first major set of upgrades were incorporated into the Block 25 F-16Cs, which had an improved cockpit, a new wide-angle HUD, and the new APG-68 radar system. The following year, the Block 30/32-series birds appeared with a bigger computer memory, new fuel tanks, and the same kind of common engine bay that’s on the F-15E. This means that either the General Electric F110-GE-100 (Block 30) or the Pratt & Whitney F100-PW-220 (Block 32) engine can be fitted, with only minor changes between the two variants. The biggest of these is a larger engine inlet for the F110-powered variant, which can be easily changed. In addition, the inlet of both variants, always a major contributor to the F-16’s RCS, has been specially treated with several radar-absorbing material (RAM) coatings, which radically reduces its detectability. The next major variant (it appeared in 1989) was the Block 40 (F110)/42 (F100) version, which had the new enhanced enveloped gunsight (like the F-15C/E), APG-68V5 radar and ALE- 47 decoy launchers, a GPS receiver, and provisions for a higher gross weight (42,300 lb./19,227.3 kg.). Following this (in 1991) was the Block 50/52 version, which made use of a pair of new technology, higher thrust engines (29,000 lb./ 13,182 kg.), the General Electric F-110-GE-129 installed in Block 50 birds, and the Pratt & Whitney F100-PW-229 in the Block 52s. In addition to the new engines, the Block 50/52 F-16s were equipped with a new ALR-56M RWR and a MIL-STD-1760 data bus for programming new-generation PGMs. The latest, and probably final, production variant is the Block 50D/52D version, equipped with a new 128K DLD cartridge, a ring laser gyro INS, an improved data modem (IDM) like the F-15E, and the ability to fire the latest versions of the AGM-65 Maverick and AGM-88 HARM missiles.
On the Block 15 and later models of the F-16, there are two special mounting points on either “cheek” of the air intake that can support sensors such as the LANTIRN system pods (targeting on one side, navigation on the other), the ASQ-213 HARM targeting system (HTS) pod, the Atlis II targeting pod, the Pave Penny laser tracking pod, or future precision targeting devices. The HTS pod has opened up a whole new mission for the Viper. Only 8 in./20 cm. in diameter, 56 in./142 cm. long, and weighing 85 lb./36 kg., it fits on the right-side cheek mount (Station 5 as it is called), where the AAQ- 14 LANTIRN pod would normally hang. Originally developed by Texas Instruments under a program to provide new modular targeting systems for USAF aircraft, it is the key to USAF’s effort to hold on to some kind of SAM hunting capability in the 21st century. This is particularly vital, given the age of the F-4G Wild Weasel fleet, which is rapidly drawing down. The HTS pod allows the pilot of a single-seat F-16C to do just about everything a two-seat F-4G can do with its APR-47 RWR system. Most important of these is the ability to rapidly generate ranges to target radars, as well as to provide greater discretion between different types of enemy radars. Lockheed is even working on a new version of the F-16 flight software which will allow two or more F-16s with HTS pods, GPS receivers, and IDMs (acting as data links) to work together so they can generate more accurate targeting solutions, and even feed them to other HARM-equipped aircraft with IDMs. This matter of establishing ranges to target radars is vitally important since standoff range for an AGM-88 can be roughly doubled if you know this before launch and can program it into the HARM. It also reduces the time of flight for a HARM, by allowing the missile to fly a more direct path. About a hundred of the HTS pods were manufactured and delivered by Texas Instruments (who also manufacture the AGM-88 HARM), and have been assigned to several F-16 units within ACC and overseas units.
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 tim
e 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 120° arc horizontally and 2, 4, or 6 “bars” in elevation (each bar being about 1.5° 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 17° 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 Co
mmand (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.