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 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
One criticism of the F-16, compared to its competitors, is its relatively short unrefueled range. The Israelis
