Fighter Wing: A Guided Tour of an Air Force Combat Wing tcml-3

by Tom Clancy

  All of this is packaged inside a standard Boeing Model 707-320B/VC-137 airframe with four Pratt & Whitney JT3D/TF33 turbofan engines. It is also quite expensive, having originally cost something like $270 million a copy.

  Getting into an E-3 is roughly the same as a KC-135, through a normal passenger hatch on the left side of the aircraft, where the cargo door is on the tanker. The first thing that strikes you is that the interior is much more comfortably appointed than the -135s. The interior is covered with the same kinds of sound-deadening walls as a conventional airliner, mainly to ensure the comfort of the mission crew. Along with all the display consoles and other electronic gear, they are crammed into the cabin for missions that can last most of a day (though twelve to sixteen hours is normal). The tops of all the consoles in the main cabin are covered with blue indoor/outdoor carpet, which is actually quite nice to lean on! The flight deck is roughly similar to that of the Stratotanker, though some of the controls and displays are a bit more modern than the 1960s-vintage instruments on the -135.

  As you move back through the main cabin, there are any number of large cabinets and consoles scattered throughout, which can make moving about somewhat tight. These include the main computers for the radar system, as well as the symbology/display generator systems for the controller consoles. Towards the mid-cabin area over the wings are the radar control consoles. There are fourteen of these in back-to-back rows, with a flight seat (complete with shoulder harnesses and seat belts) in front of each position. Each console is configurable by the user, and can be set up for a controller, supervisor, or mission commander. Everyone is linked by a thirteen-channel intercom system, which feeds into a bank of secure Have Quick II radios, as well as other sets capable of UHF, VHF, and HF communications. In addition, the E-3 is equipped with a JTIDS data link terminal, which does much to reduce the burden on the radio channels.

  A cutaway drawing of he Boeing E-3B/C Sentry Airborne Warning and Control System (AWACS).

  Jack Ryan Entreprises, Ltd, by Laura Alpher

  Obviously, the primary reason for this aircraft's existence is the radar system it is designed to carry. The original AWACS radar system, designated APY-1, was designed by Westinghouse after a 1972 competition with Hughes. The AWACS radar operates in the E/F band, meaning that it generates radar waves in the 2-to-4-Gigahertz (GHz) range, with a wavelength of from 7.5 to 15 cm./2.95 to 5.9 in. The radar uses the pulse-Doppler principle, relying on precise measurement of the tiny frequency shift in energy reflected from a moving target to distinguish flying aircraft from background ground clutter. This gives the radar the ability to "look down" and detect low-flying targets, as long as they are moving faster than 80 knots/148 kph.

  The normal E-3 mission crew consists of separate surveillance and control sections, each typically commanded by a senior captain. In the surveillance section, three to five technicians monitor the air traffic in a huge volume of airspace and pass on information to the control section. This is composed of two to five weapons controllers sitting at multi-purpose consoles, guiding friendly aircraft to intercept enemy or unidentified contacts. Depending on its particular mission, an AWACS also may carry senior staff officers, radar technicians, radio operators, a communications technician, and a computer technician.

  While the E-3 displays are a great improvement over the "bogey dope" screens of the old EC-121s, which required almost mystical powers to interpret, they are rapidly becoming dated. The symbology is somewhat hard to interpret, and the screens can easily become cluttered. On the positive side, the trackball "mouse" used to select or "hook" targets on the screens is quite easy to use, and once you get used to the idea that a small symbol with a track number is an aircraft, you do quite well.

  Aft from the console area are more electronics cabinets, as well as an area reserved for passengers and off-duty personnel. While the seats are not terribly comfortable, they are an improvement over the maximum-stress environment of being "on the scope." There is also a tiny galley, as well as several small bunks which are usually reserved for spare flight crew personnel (pilots, navigators, etc.). Combat AWACS missions in excess of eighteen hours during Desert Storm were not uncommon, and spare personnel were often necessary. At the very back of the cabin is a rack of parachutes, and there's a bail-out door in the floor of the forward cabin. This, fortunately, has never had to be used, since no E-3 Sentry has ever been lost.

  A USAF Boeing E-3 Sentry Airborne Warning and Control System (AWACS) aircraft arrives in Saudi Arabia during Operation Desert Shield. Fourteen of these valuable aircraft, as well as E-3s from the Royal Saudi Air Force and NATO, provided airborne radar support during Desert Shield and Desert Storm.

  Official U.S. Air Force Photo by Jim Curtis

  The key to making this system work is the need for steady, consistent flying. Sentry pilots are trained to fly a precise, wide oval racetrack course, straight and level, avoiding any sharp banking turns that might disrupt the radar beam's normal sweep. Typical cruising altitude for an operation mission is 29,000 feet/8,840 meters (just about the height of Mt. Everest), at a maximum cruising speed of 443 knots/510 mph./860 kph. Unrefueled, the E-3 has an endurance of more than eleven hours, and the aircraft has a receptacle for in-flight refueling which can stretch the endurance to twenty-two hours, a limit set by the supply of lube oil for the four JT3D/ TF33 engines. On these marathon aerial-surveillance missions, the endurance of both the flight crews and mission personnel is stretched to the limit. This has been pointed to as one of the weaknesses of the AWACS community. In the past, there have frequently been difficulties with flight personnel getting adequate rest between missions, as well as with the excessive number of "on-the-road" days that have been a hallmark of the AWACS lifestyle for almost twenty years. Unfortunately, since AWACS aircraft are a favorite instrument of politicians trying to find out what's happening in a trouble spot, the lifestyle of the AWACS crews is unlikely to change much.

  The interior of a USAF Boeing E-3 Sentry AWACS aircraft looking aft. Visible are the consoles, where the controllers sort out airborne contacts and supervise flight operations.

  Boeing Aerospace

  Most of the thirty-four E-3s in USAF service are assigned to three operational Airborne Air Control squadrons (the 963rd, 964th, and 965th), and one training squadron (the 966th) of the 552nd Air Control Wing based at Tinker AFB, Oklahoma. One aircraft is assigned to continuing research and development work at the Boeing plant in Seattle, and a few are permanently stationed in Alaska, assigned to the Pacific Air Force (PACAF) commander. Detachments have been, and continue to be, deployed to trouble spots all over the world. These started with a movement by the Administration of President Jimmy Carter of a three-aircraft detachment of E-3s to Saudi Arabia to keep an eye on the Iran/Iraq War. It was called ELF-1, and what was planned as a deployment of several months eventually wound up lasting over eleven years. It seems to be the lot of the AWACS community to spend their lives on the road, keeping watch on the world's trouble spots.

  Even though some of the E-3's systems are getting to be a bit dated right now, the E-3s of the AWACS fleet are the crown jewels of the USAF fleet, and represent the most valuable aircraft that an aerial commander can be assigned. Their presence on the aerial battlefield greatly improves the efficiency of any force that they support, thus explaining why USAF leaders call the AWACS fleet a "force multiplier." This may explain the tolerance for the high costs of developing, operating, and maintaining such a force. The technical problems of developing a reliable and effective airborne warning and control system are so great that only one other nation has ever really managed it — Russia, with its A-50 Mainstay AWACS, based on an IL-76 heavy transport airframe. Meanwhile, NATO, Saudi Arabia, and a few other very friendly nations have bought versions of the E-3.

  As the E-3 fleet heads into its twentieth year of service, there are strong plans to upgrade the system so that it will be ready to continue its valuable service into the 21st century. The major points of the planned E
-3 upgrade program include:

  • GPS—It has taken a while, but the E-3 is finally going to get a GPS receiver to help improve both navigational accuracy of the AWACS aircraft itself, as well as the quality of the information it supplies.

  • Radar System Improvement Program (RSIP)—The RSIP upgrade is a long-overdue series of improvements to the APY-1/2 radar systems that includes an improved radar computer, a more modern graphics processor for the radar operators' consoles, as well as upgrades to the radar system itself. All of these should allow the AWACS controllers to handle more targets with less clutter on the displays. In addition, the software rewrite that is included with RSIP will allow for things like "windowing" (display-within-a-display) capabilities, as well as the ability to detect low-observable/first-generation stealth aircraft. While the technology behind this last capability is highly classified, it probably centers around the same kind of "broad band" processing technology that is used on submarines. Westinghouse is the prime contractor on the RSIP upgrade, and will begin installation in the late 1990s.

  As the E-3 completes its second decade of service, it is time for the Air Force to start thinking about a Sentry replacement. The problem, of course, is finding the money, as well as deciding what kind of aircraft the USAF wants to base it on. As with the other models of first-generation American jet transports, the 707 was designed to very conservative 1950s engineering standards; and after forty years of steadily advancing technology, it's too heavy, it's a fuel hog, and it's too hard to update with modern digital flight control systems. When Japan decided to join the AWACS club, the Japanese ordered the basic E-3 mission package on a modern airframe, the wide-body, twin-turbofan Boeing 767. With a two-person flight crew and better fuel economy, operational costs should be lower, but this is still going to be a very costly aircraft.

  In the future (around 2010 to 2020), it should become possible to do away with the radar rotodome and rely on conformal phased-array and synthetic aperture antennas to integrate the AWACS air surveillance mission and the Joint-Stars ground-surveillance mission onto a single platform. This could well be a very high-flying stealthy aircraft, with most of the crew replaced by advanced computers. AWACS, with a top speed of only Mach.78 and a radar cross section somewhat greater than the broad side of an average office building, has been fortunate in its long operational career, since it has never faced an enemy with long-range, high-speed anti-radiation missiles. Right now, though, with the E-3 in the prime of its service life, such a solution is several decades away from fruition, and the Sentry is still the undisputed king on the aerial chessboard.

  Ordnance: How Bombs Got "Smart"

  IF you read analyses of military aviation, especially in the mass media, you might get the impression that air forces are concerned with aircraft, not with weapons. The guy who flies a plane into the wild blue yonder is a steely-eyed, heroic officer and gentleman. The guy who tinkers with missile guidance systems at a workbench is an enlisted nerd. Aircraft are more glamorous than ordnance. But without ordnance to deliver on targets, the only thing airplanes can do is watch. And while we have seen that reconnaissance is a valued and important mission for aircraft, it is the delivery of ordnance on enemy targets that makes airpower a credible combat force.

  The story of today's ordnance is the story of how bombs and bullets got "smart." Since the end of World War II, most of the developmental money for new conventional (i.e., not nuclear, chemical, or biological) weapons has gone into guided systems that have held the promise of "one round, one hit." Some systems, like the Sidewinder air-to-air missile and the Paveway laser-guided bombs, have almost fulfilled that promise. Others have not done so well. Nevertheless, after the 1991 Persian Gulf War, when the 10 % of the weapons dropped that were smart did something like 90 % of the damage to critical strategic targets, you can count on all types of weapons getting smarter. While the use of the unguided rocket or "dumb" bomb may not yet be over, their days are clearly numbered.

  Meanwhile, the variety of weapons that a modern combat aircraft can carry simply boggles the mind. Recently, another defense writer contacted me to ask about Air Force munitions programs. So confusing was the variety of the programs we discussed, that we decided this book would try to explain as many of the different things that U.S. Air Force aircraft can shoot at, launch at, or drop on our enemies as possible.

  AIR-TO-AIR MISSILES

  Though rapid-firing cannons are a vital part of the weapons mix that make fighters both dangerous and effective, bullets aren't smart. Once they leave the muzzle of a gun, they can only follow a ballistic path determined by the laws of physics, no matter what the target does. A guided missile, on the other hand, can alter its flight path after it is launched, which greatly increases the probability of a hit. If you look at the world record books since the end of the Korean War, the vast majority of air-to-air kills have been achieved by guided air-to-air missiles (AAMs). Maybe not as righteous as a gun kill, but as any fighter jock will tell you, "A kill's a kill!"

  AIM-9 Sidewinder Missile

  The first experiments with guided AAMs were done in Nazi Germany during World War II. In an attempt to keep their fighters out of range of the defensive machine guns of the massed air fleets of bombers and fighters attacking their homeland, the Germans developed a series of air-to-air missiles. Luckily for the Allied air forces, the Ruhrstahl X-4 came too late to make it into service. This compact, wire-guided missile was designed to be "flown" by the pilot of the firing aircraft using a small joystick. It was a halting step on the way to the AAMs of today, but it was a first step nevertheless.

  Following the war, a number of nations began to develop SAM and AAM designs, hoping to knock down the fleets of nuclear bombers that were expected to dominate the next major conflict. Most were designed to use the new technology of radar that had matured during World War II. The problem with radar-guided missiles was that they were relatively heavy, vastly complex, and required the firing aircraft/battery to track the target with its own radar. In order to allow the missile to get within lethal range of the target aircraft, you had to either "illuminate" the target with a radar beam (called a fire-control radar), or track the outgoing missile in flight and radio flight commands (called command guidance or "beam riding"). Early fighters equipped with these bulky systems had to be large, placing aircraft designers of the day under great pressure to build aircraft with performance equal to their smaller, gun-armed competitors. It seemed for a time that designers of missile-armed fighters would just have to grit their teeth and wait for technical advances in power plants, electronics, airframes, and computers to make the promise of air-to-air missiles a reality.

  Then suddenly, out of a brilliant, unorthodox scientist's garage laboratory in the high desert of California, came an elegantly simple solution to the problem of missile guidance. The scientist was Dr. William B. McLean, at the Naval Ordnance Test Station (NOTS) at Inyokern, California (today the Michelson Laboratory of the U.S. Naval Weapons Center at China Lake, California). In the late 1940s, in his home garage workshop and on his own time, he built a simple device that could track an aircraft by the heat emissions from its power plant. This meant that a missile seeker could be developed to track a target without any sort of radar guidance from the firing battery or aircraft.

  The key was a small electronic detector, called a photovoltaic cell, which was capable of detecting heat — or infrared radiation emissions in the short-wavelength region of the electromagnetic spectrum. The early infrared seekers used detectors based on lead sulfide, a material whose electronic characteristics are altered when it becomes saturated by infrared radiation. These seekers were not looking for the heat given off by the exhaust gases of a jet engine (as mistakenly reported for decades). On the contrary, what the tracking elements of the first-generation heat-seeking missiles were looking for was hot metal, or more specifically, the infrared radiation given off by the hot metal of jet or piston engine exhaust ports. The major technical advantage of infrared seeke
rs is that they can be more compact, lighter, and cheaper than radar missile seekers. This allowed Dr. McLean and the engineers at NOTS to design a missile, initially known as Local Project (LP) 612, that only weighed about 155 lb./70.45 kg., in a tubular body only 5 in./12.7 cm. in diameter. To save money (which he did not have anyway), McLean used airframes from unguided 5 in./12.7 cm. High Velocity Artillery Rockets (HVARs), into which he packed the motors, warheads, and electronics. At the rear of each of the fixed tail fins is a small device that looks like a metal pinwheel. This is called a rolleron, and is used to stabilize the weapon while it is in flight. It's one of the tricks thought up by Dr. McLean and his team to help keep the Sidewinder on a stable course, and uses the missile's own slipstream through the air to generate gyroscopic motion to dampen any oscillations induced by the guidance system. The rolleron was on the first missile, and is still there today. LP612 also had the advantage of being a "fire-and-forget" weapon — the pilot does not guide the weapon after firing. Tactically, this means the firing aircraft is free to maneuver or evade once the weapon is launched.