The winning Grumman design (Design 303E) featured engines in separate nacelles, set well apart from each other so that damage to one of them would have minimal effect on the other.
Most of the aircraft structure was made of conventional aluminum alloys, with some components being made up of steel. About 25 percent of the empty weight was made up of titanium alloy, which was used for the wing box, wing pivots, upper and lower wing skins, the intakes, rear fuselage skins, as well as the hydraulic lines.
Fuselage
The main central and rear area of the fuselage consisted of two separate engine nacelles joined together by a shallow flat area known as a "pancake". At the extreme rear of the aircraft, this pancake is little more than a decking between the engine pods. This leaves a deep tunnel between the engines which imposes a drag penalty. However, it adds to overall lift, gives an extra attachment area for weapons pylons, and provides some additional fuselage space for fuel and equipment. The rear part of the broad between-engines pancake is gently curved upwards to reduce both the supersonic trim drag and the negative zero-lift supersonic pitching moment.
A similar arrangement was used in the Soviet MiG-29 and Su-27 fighters, which were designed much later. One of the problems with this configuration is that it puts the thrust line of each engine rather far outboard from the centerline, producing sudden and violent nose slices (rotation in yaw) in the event of a single engine failure.
Air is admitted to the engines via two large, rectangular-shaped, sharp-lipped intakes, one mounted on each side of the fuselage. The edges of the intakes are swept sharply backward from top to bottom, ensuring that adequate amounts of air get into the engine at high angles of attack. These intakes are mounted well outboard of the fuselage sides, far enough away that turbulent boundary layer air is kept from entering the engine without the use of complex diffuser systems such as those fitted to the F-4 Phantom. Because of the overall dihedral of the wing glove box, the intakes are canted outwards at the bottom. However, even at the top of the intakes where they are closest to the fuselage, the inner wall of the intake is still at least 8 inches away from the fuselage.
The intakes are of multi-ramp wedge configuration and offer a straight path for the air entering the engines. Each intake has a pair of adjustable ramps attached to the upper part of the inner intake. Hydraulic actuators in the upper part of the intake adjust the positions of the first and second ramps in the upper surface of the inlet and of the diffuser ramp located further aft, reducing the inlet air to subsonic velocity before admitting it to the engine. A gap between the back edge of the second ramp and the leading edge of the diffuser ramp allows bleed air to escape from the inlet, passing overboard via a bleed-air door in the outer surface of the inlet. The inlet ramps are under the automatic control of a computer, which calculates the optimal position for the ramps based on engine speed, air temperature, air pressure, and angle of attack. At supersonic speeds, the hinged panels narrow down the throat area while diverting the excess airflow out of the ducts through aft-facing spill doors at the top of the intakes. At low speeds (especially during takeoff) when more engine air is needed, this airflow is reversed and extra air is sucked in via the spill doors.
The single-wheeled main landing gear elements retract forwards into wells inside the wing glove box, rotating 90 degrees to lie flat. The twin-wheeled nose unit retracts forward into a well in the nose.
Integral fuel tanks are provided between the wing spars of the outer section, holding 295 US gallons each. The tapering section of the rear fuselage aft of the wing carry-through structure carries an additional 648 US gallons of fuel, and a 691-US gallon tank is fitted between the cockpit and wing carry-through structure. Two feeder tanks combined offer a 456-gallon capacity, bringing total internal fuel capacity to 2385 US gallons. A 267-gallon external drop tank can be carried on hardpoints underneath each air intake. The Tomcat is equipped for in-flight refuelling via a retractable probe on the starboard side of the fuselage.
There are door-type speed brakes at the rear of the pancake both above and below, the lower brake being split in two to accommodate the arrester hook. The brakes can be extended at angles as great as 60 degrees. The use of brakes both above and below the fuselage minimizes the trim changes when they are deployed. The lower airbrake does have a danger of scraping on the carrier deck upon landing, so it is restricted to extension angles of only 18 degrees when the landing gear is down. At the extreme end of the decking are a large fuel dump pipe and housings for electronic warfare equipment.
The Tomcat does not have fly-by-wire or artificial stability mechanisms. The control system consists of conventional rods and cables, springs and weights, servos and boosters. All of the control surfaces (including the variable sweep) have direct mechanical linkages, and only the spoilers have electrical drives.
Wings
The variable-sweep wing panels are supported by a massive wing carry-through structure which spans the upper center section of the aircraft, terminating at each end in a large pivot point for the outer moveable wing panels. This carry-through structure is made from electron-beam welded titanium alloy. The fixed wing glove structure forms a diamond-shaped surface. The beam has slight dihedral to reduce the cross sectional area of the central fuselage, reducing drag and assisting in the area-ruling of the fuselage. In order to maintain a snug fit between the trailing edge of the wing and the upper surface of the rear fuselage, the rear edges of the fixed wing glove uses a set of inflatable canvas bags. Teflon paint on the underside of the wing help to ensure that there is minimal abrasion of these bags as the wings are extended or retracted.
The wings feature variable sweep, ranging from a minimum of 20 degrees to a maximum of 68 degrees. At maximum sweep, the wing trailing edges are aligned with the leading edges of the horizontal tails. For carrier deck storage, the wings can be set manually to an "oversweep" of 75 degrees. This is possible because the wings are set slightly higher than the horizontal tails. This makes it unnecessary for have a folding wing for carrier stowage.
Wing sweep angle is automatically controlled by an AiResearch CP-1166B/A central air-data computer. For takeoffs and landings, as well as for low-speed flight, the wings are set at a minimum sweep of 20 degrees, which gives an overall span of 64 feet. For supersonic dash, the wings sweep back to 68 degrees. Throughout the entire speed/maneuver regime, an automatic wing sweep program matches the sweep angle to the optimal position. However, the system can be manually overridden by the pilot in an emergency. Should the wings get stuck in the fully-aft position, the F-14A can still land safely at 200 mph with 4000 pounds of fuel or at 166 mph with 2000 pounds of fuel, in spite of the fact that the wing flaps are inoperative when the wing is swept.
The wing has no conventional ailerons, roll control being provided at low speeds by wing-mounted spoilers and at high speeds by the differentially-moving horizontal tailplane. When wing sweep is greater than 57 degrees, the wing spoilers are automatically locked down, and roll control is provided completely by the differentially-moving horizontal stabilizers.
The full-span trailing edge flaps have a small inboard section and a larger outboard section. The normal two-section flap can be extended at angles of 35 degrees for landing or can be extended up to 10 degrees when used for maneuvering in order to generate more lift and permitting tighter turns. Initially, the maneuver flaps were manually controlled by a thumbwheel on the pilot's control column, but on production block 90 aircraft, the maneuver flaps were placed under the control of the air data computer. The normal two-section flap can be used at wing sweep angles of up to 50 degrees, with the air-data computer automatically locking out the flaps as the wing is swept further aft. Auxiliary flaps are located even farther inboard, and are actually on the trailing edge of that part of the wing that retracts into the fuselage. These auxiliary flaps can only be used when the wing is fully swept forward.
Leading-edge maneuvering slats occupy virtually the full span of the outer wing panel leading edge. The leading edge slats are power-driven to 7 degrees for air combat maneuvers and to 17 degrees for landing. To improve combat maneuverability, the slats and outboard flap sections can be deployed while the wing is in the fully-forward position.
Two small triangular-shaped vanes were mounted on the leading edge of the wing gloves. These vanes are normally retracted, but are extended at supersonic speeds under the control of the air-data computer. The purpose of these vanes is to generate additional lift ahead of the aircraft's center of gravity, which helps to compensate for a nose-down pitching moment that takes place at supersonic speeds. These vanes are automatically deployed when the speed exceeds Mach 1.4 in order to push up the nose and unload the tailplanes, giving them enough authority to pull 7.5 g at Mach 2. The vanes can be manually deployed between Mach 1 and Mach 1.4, but will not operate when the wing sweep is less than 35 degrees because that would lead to too much pitch instability at low speeds. However, the benefit of the vanes proved in practice to be only marginal at speeds below Mach 2.25, and since they added weight and complexity, in the field they were locked shut and their actuators were removed.
The F-14 employs a system known as Direct Lift Control (DLC) for automatic control of attitude during carrier landings. When DLC is engaged, the spoilers on the upper wing pop up into what is known as the "neutral" position. When these spoilers are lowered, instant lift is generated with no need for an attitude change.
The Tomcat does not have fly-by-wire or artificial stability mechanisms. The control system consists of conventional rods and cables, springs and weights, servos and boosters. All of the control surfaces (including the variable sweep) have direct mechanical linkages, and only the spoilers have electrical drives.
Vertical Tails
The original Grumman Design 303E featured a single tall vertical fin and a folding ventral strake. At Navy insistence, Grumman switched to a twin-tail configuration at the last minute and replaced the large folding strake with two smaller fixed strakes mounted underneath each engine nacelle. Each of the twin tail fins holds a conventional rudder for yaw control. The twin tail fins provide an effective means of countering destabilizing flow generated by the air intakes during sustained flight at high angles of attack. In addition, the dual rudders have the added advantage of reduced height for carrier stowage.
Cockpit
The F-14A's two crew members sit in separate tandem cockpits, which gives a lower drag profile than would be possible in a side-by-side arrangement. The two-seat, tandem cockpit is enclosed by a single-piece upwardly-opening clamshell-type canopy. The pilot is in front, and the radar intercept officer is in the rear. The crew members sit on Martin-Baker GRU-7A rocket-propelled ejector seats which can be used from zero altitude/zero airspeed up to 450 knots airspeed.
There is minimal duplication of controls and instruments for the pilot and the radar intercept officer. The pilot has three displays for viewing flight, navigation and tactical data, including armament controls and flight instruments. The aft cockpit has controls and displays for the AWG-9 fire control system. The aft cockpit does have some basic flight instruments, but is not equipped with any flight controls and the F-14 cannot be flown from the back seat. The back-seater operates the radar, identifies the adversary, and guides the pilot in making an effective interception. Unlike in the Phantom, either crew member can fire a missile.
Engines
The engines for the F-14A were initially a pair of Pratt & Whitney TF30-P-412 axial flow afterburning turbofans, each rated at 12,350 lb.s.t. dry and 20,900 lb.s.t with afterburning. The TF30-P-412 was essential similar to the TF30-P-12 that had been used for the F-111B. The TF30 has a total of 16 stages of compression. The three stage fan rotates on the same shaft as the six-stage low-pressure compressor and the seven-stage high-pressure compressor. The annular combustion chamber has 8 flame cans, each with four dual-orifice burners. The single-stage high-pressure turbine is made of cobalt-based alloy and can stand temperatures as high as 100 degrees Celsius. The three stage low pressure turbine is of nickel-alloy construction. The augmentor consists of a five-zone afterburner mounted within the inner liner of the outer duct. The exhaust features a variable-geometry nozzle with movable petals which slide on curved tracks to close down to minimum area for subsonic cruise and fully opened to a convergent and then divergent profile for afterburning flight during takeoff and at supersonic speeds.
Electronics
For its primary interception role, the F-14 is equipped with the Hughes AN/AWG-9 radar fire control system. The AN/AWG-9 was derived from the AN/ASG-18 radar and fire control system developed for the abortive F-108 Rapier project, and then further developed for the Douglas Missileer and the F-111B. The AWG-9 has the ability to carry out near-simultaneous long-range missile launches against up to six targets while tracking 24 more. The antenna is a 36-inch flat plate unit. The IFF antennae are mounted directly on the plate and take the form of an array of dipoles. The output power is 10.2 kilowatts. The AWG-9 can look down into ground or sea clutter, detecting and tracking small targets flying at low level. The clutter is removed by a signal processor which uses analog filtering.
The AWG-9 has the ability to carry out near-simultaneous long-range missile launches against up to six targets while tracking 24 more. The set incorporates a lightweight 5400B digital computer. The antenna is a 36-inch flat plate unit. The IFF antennae are mounted directly on the plate and take the form of an array of dipoles. The output power is 10.2 kilowatts. The AWG-9 can look down into ground or sea clutter, detecting and tracking small targets flying at low level. The clutter is removed by a signal processor which uses analog filtering. In pulse Doppler search mode, the radar has a range of 125 miles or more.
Early Tomcats were equipped with a gimbal- mounted AN/ALR-23 infrared detection set mounted underneath the nose that could be slaved to the radar or used independently to scrutinize areas not searched by the radar. Its indium antimonide detectors were cooled by a self-contained Stirling-cycle cryogenic system. In practice, this IR sensor proved to be ineffective, and was replaced by the Northrop AAX-1 Television Sight Unit (TSU), which consists of a television camera fitted with a stabilized telephoto lens. Displays appear on both the pilot's and the WSO's control panels. The system can be used to spot an enemy visually and to identify him early, hopefully preventing Tomcat pilots from shooting down friendlies. The first production installation of the TSU was incorporated in 161597, the first Block 125 aircraft.
The Central Air Data Computer (CADC) is an AiResearch CP-1166B/A. It uses data from sensors which measure pitot and static pressures, air temperatures, and angle attack to select the optimal wing sweep angle and sends commands to the control surfaces. It also passes to the Air Inlet Control Systems (AICS) the information it needs to set the inlet ramps to their optimal positions.
The AN/ARA-63 aircraft approach control system uses the AN/SPN-41 and the AN/TRN-28 transmitting sets. It provides primary or backup instrument approach capability.
The spine of the Tomcat contains blade antennae for the UHF/TACAN and data link/IFF. Radio and navigation equipment on board the aircraft include the APX-71 IFF transponder, AXX-76 IFF interrogator, ARC-51 (later switched to ARC-159) UHF radios, ARR-69 auxiliary receiver, KY-58 cryptographic system, ASN-92 CAINS II (Carrier Aircraft Inertial Navigation System II) inertial navigation system, APN-154 beacon augmenter, APN-194 radar altimeter, Gould ARN-84 TACAN and ARA-50 automatic direction finder.
A Harris ASW-27B digital datalink provides high speed data communication between the Tomcat and ship-based command and control systems. This system can also be used to link to the Airborne Tactical Data Systems of Grumman E-2C Hawkeye early warning aircraft. This system can be used to pass target data back and forth between aircraft, extending the effective radar range. It helps the Tomcat crew to get a broader picture of the tactical situation, and allows the aircraft to operate without using its own sensors when tactically appropriate to do so.
The Tomcat initially carried AN/APR-25 and AN/APR-27 radar warning receivers. These were subsequently replace by the AN/ALR-45 and -50 and later by the AN/ALR-67. These units are designed to warn crews of SAM launches. A major upgrade updated this equipment to deal with the SA-6 Gainful missile and its associated Straight Flush radar. The Tomcat is equipped with the Goodyear AN/ALE-39 chaff and flare dispensing system, which has replaced the AN/ALE-29 originally carried. The Tomcat initially entered service with the Sanders Associates AN/ALQ-100 noise deception jammer, but this has been replaced with the Sanders AN/ALQ-126A. The latter unit formed part of the PRIDE defensive avionics suite, along with the ALR-45 and the ALR-50 radar warning receivers. Plans to fit the AN/ALQ-165 Advanced Self-Protection Jammer (ASPJ) were cancelled when this equipment failed to pass its development tests.
Armament
Even today, the armament of the F-14A Tomcat remains the most potent of that of any interceptor currently in service. It has four basic components--an internal cannon and Sidewinder infrared homing missiles for short-range encounters, Sparrow semi-active radar homing missiles for intermediate-range encounters, and Phoenix missiles for long-range encounters. All of these weapons are directed and controlled by the powerful AN-AWG-9 fire control system.
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Phoenix:
The Hughes AIM-54A Phoenix missile is the primary armament of the F-14A, and the Tomcat was originally designed with this missile in mind. The Phoenix missile is propelled by a single-stage Rocketdyne MK47 solid-fuel rocket motor, which gives a velocity at burnout of Mach 3.8 at low altitudes, although Mach 5 can be achieved at high altitudes in the long-range mode. The missile has four fixed delta-shaped wings and is steered by tail-mounted control surfaces. On trials, the missile has been able to maneuver at 17 g. The fuselage and aerodynamic surfaces of the Phoenix are made from metal, but the fuselage is covered with ablative thermal insulation. The missile is 13.2 feet long, the body is 13 inches wide, and the wing span is 3 feet. The launch weight is about 985 pounds. The missile has a 132-pound annular blast fragmentation high-explosive warhead. So far as I am aware, the Phoenix is not nuclear-capable.
After launch, the Phoenix can use three different types of guidance-- autopilot, semi-active radar homing, and fully-active radar homing. For long-range shots, the missile generally flies a pre-programmed route immediately after launch under autopilot control. At midcourse, the nose-mounted radar seeker takes over, operating in semi-active mode, homing in on radar waves reflected off the target from the Tomcat's AWG-9 radar. Once it gets within about 14 miles of the target, the Phoenix's own DSQ-26 radar takes over for the final run in to the target, and the missile operates in fully-active radar homing mode. At this time the missile is completely independent of its launching aircraft, and becomes "fire-and-forget".
Some reports have suggested the existence of a "flyout" mode in which the missile can be launched at heavily-jammed targets upon which the AWG-9 radar is unable to achieve a lock. In such a mode, the missile flies most of the way to the target under autopilot control, switching over to its built-in seeker for the final approach.
One of the more advanced features of the AWG-9/Phoenix weapons system is the ability to track and engage multiple targets at the same time. Track-While-Scan (TWS) mode is used for multiple-target tracking and multi-shot Phoenix engagements. In TWS mode, the AWG-9 can carry out simultaneous long-range missile attacks against up to six targets, while tracking 24 more. As each target within the region of sky being scanned is detected, the AWG-9 determines its range and angular position and this information is passed along to the computer where it is compared to the predicted positions of the targets already detected. If the newly-detected target can be correlated with an already-known target, the target's track file is updated with the current position. If not, then a new track file is opened for what is presumed to be a new target. The computer then assigns threat priorities to each track. In this mode, each target is not continually illuminated by the radar, and the Phoenix missile guidance system receives only samples of radar data. Maximum missile range in this mode is about 90 km.
In Range-While-Search (RWS) mode, the set provides range and angular data without stopping the normal antenna TWS search pattern.
The Pulse-Doppler Single-Target Track (PDSTT) mode is used when a single target is to be tracked. The AWG-9 antenna is locked on to a single long-range target at ranges of up to 130 km. The missile can be launched at 100 km range. A Jam Angle Track (JAT) facility can be use to provide range, speed, and angular information on targets being protected by ECM. In this mode, the radar can be slaved to the aircraft's electro-optical sighting unit. The AWG-9 also has conventional pulse modes for use at short and medium ranges.
On maximum-range missions, the Phoenix is usually lofted into a high trajectory designed to reduce interference between the AWG-9's powerful transmitter and the missile's receiving system. The flight time on such missions can be up to three minutes.
The Tomcat has the capability of carrying up to six Phoenix missiles, four on individual pallets mounted underneath the fuselage and one on each of the fixed wing glove pylons. However, in typical operations, the usual weapons load is four Phoenix, two Sparrows, and two Sidewinders. The original specification called for six Phoenix missiles, but it was found that the deck impacts during carrier landings were too hard when carrying six Phoenix missiles, so the full load of six Phoenixes is rarely carried.
The first Phoenix launch from a Tomcat took place on April 28, 1972. During a later test, a Phoenix missile hit a target which had been flying at a distance of 116 miles when the missile was launched. In November 22, 1973 a single Tomcat fired six Phoenix missiles in 38 seconds while flying at Mach 0.78 at 24,800 feet over Point Mugu, California. The targets were six drones. One Phoenix missile failed and a second was released against a drone which veered off course, but the other four scored direct hits. In other tests, the AWG-9/Phoenix combination has scored hits against Bomarc missiles simulating the MiG-25 Foxbat and against drones simulating the Tu-26 Backfire. Others test verified the capability of the Phoenix against sea-skimming anti-ship cruise missiles and against violently-maneuvering targets. The AIM-54A was approved for service use on January 28, 1975.
The AIM-54B had improved resistance to jamming, and was introduced into service in 1983. It had sheet-metal wings and fins instead of honeycomb structure, non-liquid hydraulic and thermal conditioning system, and somewhat simplified engineering.
The AIM-54C had a higher-thrust motor, an improved warhead, fully solid-state electronics, and an improved fuse that was better capable of detonating the warhead at the precise moment to maximize its destructive effect on the target. The AIM-54C had better electronic counter-countermeasures capability, allowing it to cope with small, low-altitude targets, being able to discriminate between the true target and any "chaff" that might be released in an attempt to break lock-on. The A and B electronics were a hybrid between the tube electronics of the late 1960s and the discrete solid-state technology of the 1970s, whereas the C was entirely solid state. The AIM-54C has the ability to take on targets at greater range or higher altitudes than can the A version, and can cope with higher degrees of target maneuverability. The goal was to make the Phoenix a better counter against the Soviet AS-4 Kitchen and AS-6 Kingfish stand-off missiles. The move to field an improved Phoenix missile may have been at least partly spurred by the fear that the Soviets may have been able to get their hands on one or more of the earlier AIM-54As that had been supplied to Iran before the fall of the Shah and the rise of the Islamic fundamentalist regime that now controls that country. Full production of the AIM-54C began in 1983.
It is not very often that Phoenix missiles are fired during training, since they cost over a million dollars a shot. The Phoenix missile has never been fired in actual combat.
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Sparrow:
The Sparrow missile was initially known as the Sperry XAAM-N-2 Sparrow I, and first entered service in July of 1956. The fully-active Sparrow II was never built. The current semi-active radar homing Sparrow III entered service with the F3H-2M Demon in January 1958. This missile was redesignated AIM-7A in 1962. Shortly thereafter, the manufacture of this weapon was turned over to Raytheon.
The AIM-7C, D, and E versions of the Sparrow semi-active radar homing missile were used in Vietnam with disappointing results. The Sparrow had originally been designed to attack subsonic, non-maneuvering, large targets such as bombers. If fired against maneuvering targets or against targets flying below 5000 feet, it usually missed. In the Vietnam War, only 9 percent of the Sparrows launched in anger actually hit their targets. In all fairness, however, some of the disappointing results with the Sparrow can be blamed on the Rules of Engagement that were in force at the time, which generally forbade the launch of Sparrows during beyond visible range encounters (where they could have been the most effective), lest they inadvertently be fired against friendlies.
The first Sparrow version to be used by the F-14A was the AIM-7E-2, which had been used in the latter stages of the Vietnam war. It contained numerous "fixes" intended to cure some of the problems of reliability that had been encountered in Vietnam. Among these were the use of clipped wings, an improved autopilot, and better fusing. In the AIM-7F that was first introduced in 1977, solid-state electronics were substituted for the miniature vacuum tubes of the earlier versions. This miniaturization enabled the warhead to be moved forward of the wings, with the aft part of the missile being devoted almost entirely to the rocket motor. The extra space that was made available by the introduction of solid-state miniaturization made it possible to introduce a dual-thrust booster/sustainer rocket motor that enabled the effective range of the Sparrow to be essentially doubled (up to 28-30 miles) in a head-on engagement. The AIM-7L had fewer tubes and more solid state features. The AIM-7M introduced in 1982 featured a inverse-processed digital monopulse seeker which was more difficult to detect and jam and provided better look-down, shoot-down capability. The AIM-7P was fitted with improved guidance electronics including an on-board computer based on VLSIC technology. It is intended to have better capability against small targets such as cruise missiles and sea-skimming antiship missiles.
The AIM-7M is 12 feet long and has a launch weight of about 500 pounds. The missile carries a 85-pound high-explosive blast fragmentation warhead. It has two sets of delta-shaped fins--a set of fixed fins at the rear of the missile and a set of movable fins at the middle of the missile for steering.
The AIM-7M is usually carried in pairs on the bottom rail of the wing glove pylons of the Tomcat, but up to four additional Sparrows can be carried semi-recessed in slots underneath the belly. However, this space is usually reserved for four AIM-54 Phoenix missiles. After Sparrow missile launch, the F-14 must continue to illuminate the target with its radar in order for the missile to home in for a kill. For the F-14, this means staying within a 65-degree cone so that the antenna of the AWG-9 will be able to follow the target. Unlike the Phoenix, only one AIM-7 can be guided at a time and only one target can be engaged at any one time.
At one time, there were plans to adapt the F-14 to the AIM-120 AMRAAM missile, but it now appears that there are no current Defense Department plans for such a conversion.
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Sidewinder:
The Sidewinder infrared homing missile dates back to 1956, but the missile has been continuously upgraded over the years. The Tomcat can carry four AIM-9 Sidewinders (two on each wing glove pylon), but the usual load is two, mounted one each on outboard shoulder pylons attached to the fixed wing glove section.
Early F-14As carried the AIM-9J, which was the first major post-Vietnam improvement of the Sidewinder missile. The J model had an expanded target-engagement cone which enabled it to be launched at any spot in the rear half of a target aircraft rather than merely at its exhaust. Compared with the Vietnam-era AIM-9G, it had a more powerful motor and an improved warhead. The AIM-9J introduced the Sidewinder Expanded Acquisition Mode (SEAM), which slaved the seeker head of the missile to the radar when in "dogfight" mode, which enabled the AIM-9J seeker head to be uncaged, slewed toward a specific target by the aircraft radar, and made to track that particular target only. The AIM-9H introduced some minor improvements. The AIM-9L introduced in 1979 was "all-aspect", and was no longer limited to engaging an enemy aircraft from the rear. The seeker head was more sensitive and was able to pick up heat from the friction off the leading edges of an aircraft's wing and was able to distinguish between aircraft and decoy flares. The AIM-9L also uses a higher-impulse rocket motor, a more powerful warhead, and a proximity fuse rigged to blow outward toward the target in order to ensure better probability of a kill. The AIM-9M introduced in 1982 had better capability to distinguish between aircraft and decoy flares, and has a low-smoke rocket motor so that it is less likely to be seen by its prey. The number of vacuum tubes was reduced to two.
The AIM-9 Sidewinder is 9.4 feet long, has a wingspan of 25 inches and a diameter of 5 inches. The missile has four tail fins on the rear, with a "rolleron" at the tip of each fin. These "rollerons" are spun at high speed by the slipstream in order to provide roll stability. The missile is steered by four canard fins mounted in the forward part of the missile just behind the infrared seeker head. The Sidewinder missile has a launch weight of about 180 pounds, and a maximum effective range of about 10 miles. The blast-fragmentation warhead weighs 21 pounds. Despite the advanced age of the basic design, the all-aspect Sidewinder remains a potent threat, exceeded in effectiveness perhaps only by the Russian-built Molniya/Vympel R-73 (known in the West as the AA-11 Archer) which combines aerodynamic and thrust-vectoring control systems.
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Cannon:
For really close-in encounters, the Tomcat is provided with an internally-mounted cannon. The 20mm General Electric M61A1 Vulcan rotary cannon is carried on the port side of the forward fuselage just below the cockpit. A muzzle gas diffuser is fitted to prevent gun gases from getting sucked into the engine intakes where they could cause engine flameouts. A total of 675 rounds of ammunition are carried in a drum. When the guns are fired, the empty cases are returned to the drum rather than being ejected overboard. This prevents the center of gravity from shifting when the guns are fired, and, in addition, prevents the spent shells from being sucked into the air intakes.
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Bombs:
The F-14A can carry up to 14,500 pounds of bombs and rockets, although it was not originally assigned a ground-attack mission. The under-fuselage pallets which ordinarily carry Phoenix missiles can also mount bomb racks for 1000-pound Mk 83 or 2000-pound Mk 84 bombs or other free-fall weaponry. VF-122 dropped the first bombs from a Fleet Tomcat on August 8, 1990. For a while, an advanced bomb-equipped F-14 Tomcat was pictured as a replacement for the General Dynamics A-12 Avenger II, cancelled in December 1990. Today, the training syllabus includes some emphasis on air-to-ground strike, although such missions would only be carried out in a relatively permissible combat environment because of the high cost of the Tomcat. Initially, the Tomcat could carry only conventional "dumb" bombs, and had no precision-guided munition capability except when operating in conjunction with a separate laser designator aircraft. Software for a ground attack mission has now been installed on all F-14Bs and Ds, as well on some F-14As.
Production Line Changes
As production of the F-14 got underway, several changes were introduced on the production line.
Block 70 (beginning with 159978) introduced the production standard wing glove fairing with shorter outboard wing fences on the top.
The beaver tail and air brake were modified from BuNo 159241 onward (the first Block 75 Tomcat). Earlier aircraft had their beaver tails cut down (with dielectric fairings removed) to a similar shape. The last Block 85 aircraft (159588) introduced the new AN/ARC-159 UHF radio in place of the AN/ARC-51A.
From 159825 (the first Block 90), a small angle of attack probe was added to the tip of the nose radome. High angle of attack performance was also improved by the provision for automated maneuvering flaps.
From Block 100 onward, a slip clutch and coupler installation was added to the flap/slat system, fuel system changes were made, AN/AWG-9 reliability improvements were incorporated, and numerous anti-corrosion measures such as seals, baffles, and drain holes were introduced.
The last aircraft of Block 110 (BuNo 161168) introduced AN/ALQ-126 antenna to the beaver tail and above and below the wing gloves.
10 early Block 60/65 F-14As (BuNos 158613/158618, 158620, 158624, and 158626/158637) were refurbished and modified to Block 130 standards for service with VF-201 and VF-202 at NAS Dallas.
Serial numbers of Grumman F-14A Tomcat:
157980 Grumman F-14A-1-GR Tomcat
157981 Grumman F-14A-5-GR Tomcat
157982 Grumman F-14A-10-GR Tomcat
157983 Grumman F-14A-15-GR Tomcat
157984 Grumman F-14A-20-GR Tomcat
157985 Grumman F-14A-25-GR Tomcat
157986 Grumman F-14A-30-GR Tomcat
modified as F-14B and then as F-14A(Plus).
157987 Grumman F-14A-35-GR Tomcat
157988 Grumman F-14A-40-GR Tomcat
157989 Grumman F-14A-45-GR Tomcat
157990 Grumman F-14A-50-GR Tomcat
157991 Grumman F-14A-55-GR Tomcat
158612/158619 Grumman F-14A-60-GR Tomcat
158614 modified for TARPS pod.
158613/158618 later modified to Block
130 standards.
158620/158637 Grumman F-14A-65-GR Tomcat
158620,158637 modified for TARPS pod.
158620,158624,158626/158637 later modified
to Block 130 standards.
158978/159006 Grumman F-14A-70-GR Tomcat
159007/159025 Grumman F-14A-75-GR Tomcat
159421/159429 Grumman F-14A-75-GR Tomcat
159430/159468 Grumman F-14A-80-GR Tomcat
159588/159637 Grumman F-14A-85-GR Tomcat
159591,159606,159612 modified for TARPS pod.
159610(DR-1),159613(DR-4),159600(DR-5),
159629(DR-7),159628(DR-8),159619(DR-9),
159592(DR-10),159595(DR-12),159603(DR-14),
159635(DR-15),159633(DR-16),159618(DR-17),
159630(DR-18) converted to F-14D(R).
159825/159874 Grumman F-14A-90-GR Tomcat
160299/160378 Grumman F-14A Tomcat - for Iran under serial numbers
3-863/3-892 and 3-6001/3-6050. Last one not
delivered.
160379/160414 Grumman F-14A-95-GR Tomcat
160652/160696 Grumman F-14A-100-GR Tomcat
160696 modified for TARPS pod
160887/160930 Grumman F-14A-105-GR Tomcat
160910, 160911,160914,160915,160920,
160925,160926,160930 were TARPS capable
161133/161168 Grumman F-14A-110-GR Tomcat
161134, 161135,161137,161140,161141,
161146,161147,161150,161152,161155,
161156,161158,161159,161161,161162,
161164,161168 were TARPS capable
161159(DR-1),161158(DR-3),161166(DR-6),
161133(DR-11),161154(DR-13) were converted
to F-14D(R).
161270/161299 Grumman F-14A-115-GR Tomcat
161270,161271,161272,161273,161275,161276,
161277,161280,161281,161282,161285 were
TARPS capable.
161287(KB-5) converted to F-14A(Plus), later
redesignated F-14B.
161416/161445 Grumman F-14A-120-GR Tomcat
161424(KB-1),161426(KB-2),161429(KB-3),
161418(KB-4),161428(KB-6),161433(KB-7),
161417(KB-8),161419(KB-9),161440(KB-10),
161444(KB-11),161427(KB-12),161416(KB-13),
161442(KB-14),161437(KB-15),161441(KB-16),
161421(KB-17),161422(KB-18),161425(KB-19),
161430(KB-22),161432(KB-24),161434(KB-25),
161435(KB-26),161438(KB-27) converted to
F-14A(Plus), later redesignated F-14B.
161597/161626 Grumman F-14A-125-GR Tomcat
161604,161605,161611,161620,161621,161622,
161624,161626 were TARPS capable.
16159?(KB-20),161610(KB-21),161608(KB-23),
161610(KB-30) converted to F-14A(Plus), later
redesignated F-14B.
161623 used as F-14D testbed and later
redesignated NF-14D.
161850/161879 Grumman F-14A-130-GR Tomcat
161851(KB-28),161871(KB-29),161870(KB-31),
161873(KB-32) converted to F-14A(Plus) and
later redesignated F-14B
161867 modified as F-14D testbed, later
redesignated NF-14D.
161865 modified as F-14D testbed.
162588/162611 Grumman F-14A-135-GR Tomcat
162595 modified as F-14D testbed.
162688/162717 Grumman F-14A-140-GR Tomcat
712/717 cancelled
Specification of the Grumman F-14A Tomcat:
Engines: Two Pratt & Whitney TF30-P-412A/414A turbofans, each rated at 12,350 lb.s.t. dry and 20,900 lb.s.t with afterburning.. Maximum speed: 1544 mph (Mach 2.34) at 40,000 feet, 912 mph at sea level. Cruising speed 610 mph. Initial climb rate 32,500 peet per minute. Service ceiling 55,000 feet, maximum unrefuelled range 2400 miles. Landing speed 132 knots. Minimum takeoff distance 1400 feet. Radius on combat air patrol with six Sparrows and four Sidewinders 766 miles. Dimensions: wingspan 64 feet 1 2/1 inches (swept forward), 83 feet 2 1/2 inches (swept back), length 62 feet 8 inches, height 16 feet 0 inches, wing area 565 square feet. Weights: 40,104 pounds empty, 59,7614 pounds loaded, 74,349 pounds maximum takeoff. Fuel: Maximum internal fuel 2385 US gallons. A 267 US-gallon drop tank can be carried on a hardpoint underneath each air intake. Armament: One 20-mm General Electric M61A1 Vulcan in the nose with 675 rounds. Provision for six AIM-7F/M Sparrow and two AIM-9L/P Sidewinder air-to-air missiles, or six AIM-54A/C Phoenix long-range air-to-air missiles and two AIM-9L/P Sidewinders, or four AIM-54A/C Phoenix missiles underneath the fuselage and two AIM-7F/M Sparrow and two AIM-9L/P Sidewinders on the wing glove pylons.
Sources:
-
Grumman Aircraft Since 1919, Rene J. Francillon, Naval Institute
Press, 1989.
-
Grumman F-14 Tomcat, Doug Richardson, Osprey, 1987.
-
F-14 Tomcat: Fleet Defender, Robert F. Dorr, World Airpower
Journal, Vol 7, 1991.
-
Grumman F-14 Tomcat Variant Briefing, World Airpower Journal,
Vol. 19, 1994.
-
The American Fighter, Enzo Angelucci and Peter Bowers,
Orion, 1987.
-
Encyclopedia of World Military Aircraft, Volume 1, David Donald
and Jon Lake, AirTime, 1994.
-
The World's Great Interceptor Aircraft, Gallery Books, 1989.
- Grumman F-14 Tomcat, Jon Lake, AirTime, 1998.
