The Grumman F-14 Tomcat is a supersonic, twin-engine, two-seat, variable-sweep wing jet fighter aircraft. The Tomcat was developed for the United States Navy's Naval Fighter Experimental (VFX) program following the collapse of the F-111B project. The F-14 was the first of the American teen-series fighters which were designed incorporating the experience of air combat against MiGs during the Vietnam War.
The F-14 first flew in December 1970. It first deployed in 1974 with the U.S. Navy aboard USS Enterprise (CVN-65), replacing the McDonnell Douglas F-4 Phantom II. The F-14 served as the U.S. Navy's primary maritime air superiority fighter, fleet defense interceptor and tactical reconnaissance platform. In the 1990s it added the Low Altitude Navigation and Targeting Infrared for Night (LANTIRN) pod system and began performing precision strike missions. The F-14 was retired from the active U.S. Navy fleet on 22 September 2006, having been replaced by the Boeing F/A-18E/F Super Hornet. As of 2009, the F-14 was only in service with the Islamic Republic of Iran Air Force, having been exported to Iran in 1976 when the US had amicable diplomatic relations with the then government of Shah Mohammad Reza Pahlavi.
The F-14 Tomcat was designed as both an air superiority fighter and a long-range naval interceptor. The F-14 has a two-seat cockpit with a bubble canopy that affords all-round visibility. It features variable geometry wings that swing automatically during flight. For high-speed intercept, they are swept back and they swing forward for lower speed flight. It was designed to improve on the F-4 Phantom's air combat performance in most respects. The F-14's fuselage and wings allow it to climb faster than the F-4, while the twin-tail arrangement offers better stability. The F-14 is equipped with an internal 20 mm M61 Vulcan Gatling-type gun mounted on the left side, and can carry AIM-54 Phoenix, AIM-7 Sparrow, and AIM-9 Sidewinder anti-aircraft missiles.
Fuselage and wings
The fuselage consists of a large flat area called the "pancake" between the engine nacelles and, by itself, provides about 40% of the F-14's aerodynamic lifting surface. Fuel, electronics, flight controls, and the wing-sweep mechanism are all housed in the fuselage "pancake". The wings pivot from two extensions on either side of the "pancake", called wing gloves. The twin engines are housed in nacelles below and slightly to the rear, with the fuselage smoothly blending into the shape of the exhaust nozzles. The nacelles are spaced apart 1 to 3 ft (0.30 to 0.91 m). This produces a wide tunnel between the nacelles which causes some drag, but adds considerable lift and pitching ability. The resultant tunnel provides space to carry Phoenix or Sparrow missiles, assorted bombs, or the TARPS reconnaissance pod, and increases fuel capacity and room for equipment.
The F-14's wing sweep can be varied between 20° and 68° in flight, and can be automatically controlled by the Central Air Data Computer when the pilot selects "auto" wingsweep mode. This maintains the wing sweep to give the optimum lift-to-drag ratio as the Mach number varies, but the system can be manually overridden by the pilot if necessary. When the aircraft is parked, the wings can be "overswept" to 75°, where they overlap the horizontal stabilizers to save space on crowded carrier decks. In an emergency, the F-14 can land with the wings fully swept to 68°, although this is far from optimal and presents a significant safety hazard due to greatly increased airspeed. An aircraft is typically diverted from the aircraft carrier to a landing field ashore in the rare event that would occur. The F-14 has also flown and landed safely with the wings swept asymmetrically even from an aircraft carrier in emergencies.
The wings have a two-spar structure with integral fuel tanks. Much of the structure, including the wing box, wing pivots and upper and lower wing skins is made of titanium, a light, rigid and strong material, but also difficult to weld, and costly. Ailerons are not fitted, with roll control being provided by wing mounted spoilers at low speed (which are disabled if the sweep angle exceeds 57°), and by differential operation of the all-moving tailerons at high speed. Full-span slats and flaps are used to increase lift both for landing and combat, with slats being set at 17° for landing and 7° for combat, while flaps are set at 35° for landing and 10° for combat. The twin tail layout helps in maneuvers at high AoA (angle of attack) while reducing the height of the aircraft to fit within the limited roof clearance of hangars aboard aircraft carriers. Two under-engine nacelle mount points are provided for external fuel tanks carrying an additional 4,000 lb (1,800 kg) of fuel.
Two triangular shaped retractable surfaces, called glove vanes, were originally mounted in the forward part of the wing glove, and could be automatically extended by the flight control system at high Mach numbers. They were used to generate additional lift ahead of the aircraft's center of gravity, thus helping to compensate for the nose-down pitching tendencies at supersonic speeds. Automatically deployed at above Mach 1.4, they allowed the F-14 to pull 7.5 g at Mach 2 and could be manually extended with wings swept full aft. They were later disabled, however, owing to their additional weight and complexity.
The air brakes consist of top-and-bottom extendable surfaces at the rearmost portion of the fuselage, between the engine nacelles. The bottom surface is split into left and right halves, with the arrestor hook hanging between the two halves. This arrangement is sometimes called the "castor tail", or "beavertail". The Tomcat has fully mechanical flying controls, with the only exception being the spoilers, which are hydro-electrically driven.
Engines and landing gear
Two rectangular air intakes located under the wings fed two Pratt & Whitney TF30 (or JT10A) engines, which were relatively powerful for the time (5.670/9.480 kg/t) and being turbofans allowed reduced fuel consumption while cruising, which was important for long patrol missions.
Both air intakes have movable ramps and bleed doors that are operated by the air data computer to enable enough air to enter the engine while keeping shockwaves away from the engine. The exhausts also feature variable nozzles with moving petals that open or close depending on engine state. The TF30 engine left much to be desired both in power and reliability. John Lehman, Secretary of the Navy, told Congress that the F-14/TF30 combination was "probably the worst engine/airframe mismatch we have had in years" and said that the TF30 was "a terrible engine", with F-14 accidents attributed to engine failures accounting for 28% of overall losses. Cracks in the turbines were dangerous to the point that the engine bay was reinforced in case of blade failure, to help reduce damage to the rest of the aircraft. The TF30 engines were also extremely prone to compressor stalls, which could easily result in loss of control due to the wide engine spacing, which causes severe yaw oscillations and can lead to an unrecoverable flat spin. At specific altitudes, the exhaust from a launched missile could cause the engine compressor to stall. This resulted in the development of a bleed system that temporarily reduced the power of the engine and blocked the frontal intake during missile launch. The overall thrust-to-weight ratio at maximum takeoff weight is around 0.56, which does not compare favorably with the F-15A's ratio of 0.85. The aircraft had an official maximum speed of Mach 2.34. Internal fuel capacity is 2,400 USgal (9,100 l): 290 USgal (1,100 l) in each wing, 690 USgal (2,600 l) in a series of tanks aft of the cockpit, and a further 457 USgal (1,730 l) in two feeder tanks. It can carry two 267 USgal (1,010 l) external drop tanks under the engine intakes. There is also an air-to-air refueling probe, which folds into the starboard nose. The F-14 with General Electric F110 engines had a thrust-to-weight ratio of 0.73 at maximum weight and 0.88 at normal takeoff weight.
The undercarriage is very robust, in order to withstand the harsh takeoffs and landings necessary for carrier operation. It comprises a double nose wheel and widely spaced single main wheels. There are no hardpoints on the sweeping parts of the wings, and so all the armaments are fitted on the belly between the air intakes and on pylons under the wing gloves (external fuel tanks can also be mounted directly below the intakes to increase the F-14's range, as seen in the image above).
Avionics and flight controls
The cockpit has two seats, arranged in tandem. The pilot and radar intercept officer (RIO) sit in Martin-Baker GRU-7A rocket-propelled ejection seats, rated from zero altitude and zero airspeed up to 450 knots. They have a 360° view in a canopy that is also fitted with four mirrors, one for the RIO and the others for the pilot. The canopy is still fairly traditional; being in three parts, but the overall structure is large and gives good visibility. The crews have classical controls and many older instruments, with an analog-digital hybrid lay out. Only the pilot has flight controls. No dual control version was ever made for the F-14, so the pilot starts to learn how to fly the machine using other aircraft and simulators. The main control systems are a HUD made by Kaiser, a VDI and a HSD display, that gives data on airspeed, navigation and other information.
The Tomcat was also notable for its Central Air Data Computer, the integrated flight control system used in the early versions of the fighter. It used a MOS-based LSI chipset, the MP944, making it a candidate for the first microprocessor design in history. The CADC was designed and built by Garrett AiResearch.
The nose of the aircraft is large because it carries not only the two person crew, but also a large number of avionics systems. The ECM and navigation suite are extremely comprehensive and complex. The main element is the Hughes AWG-9 X-band radar, which in the initial version included a lightweight 5400B digital system with 32 kilobytes of RAM. The antenna dish is a 36 in (91 cm) wide planar array, uses 10 kW of power, and has integrated IFF antennas. There are available several search and tracking modes, such as Track-While-Scan (TWS), Range-While-Search (RWS), Pulse-Doppler Single-Target Track (PDSTT), and Jam Angle Track (JAT). A maximum of 24 targets can be tracked simultaneously, and six can be engaged in TWS mode up to around 60 mi (97 km). Pulse-only STT mode has a maximum range of around 96 statute miles (150 km). The maximum search range can exceed 120 statute miles (190 km) and even a fighter can be locked onto at around 72–90 statute miles (120–140 km). Cruise missiles are also possible targets with the AWG-9, since this radar can lock onto and track even small objects at low altitude when in a Pulse-Doppler mode. The radar antenna dish is in the nose, and most of the radar avionics are located just behind the nose, near the pilot's position. Other avionics (such as IFF, communication radios, direction-finding equipment, etc.) are near the RIO's position, and are mostly integrated into the AWG-9 display system.
Tomcats also feature electronic countermeasures (ECM) and radar warning (RWR) systems, chaff/flare dispensers in the tail, fighter-to-fighter data link, and a precise inertial navigation system. The early navigation system was purely inertial. Initial coordinates were programmed into the navigation computer, and a gyroscope in the system would track the aircraft's every motion. These aircraft motions were sent to the navigation computer, allowing it to calculate the jet's distance and direction from the initial starting point. Later, GPS was integrated into this inertial system, providing not only more precise navigation, but providing redundancy in case either system failed.
The chaff/flare dispensers were located on the belly, at the very tip of the tail, just to one side of the arresting hook. The dispenser contained several cylinders, into which either flares or chaff could be loaded in any combination. The RWR system was arranged with 4 antennae around the aircraft, and could roughly calculate the direction and the distance of many different types of radar from various aircraft and missile types. The RWR set could also display the status of the tracking aircraft's radar. It could differentiate between search radar, tracking radar, and missile-homing radar. The electronic countermeasures system could analyze incoming radar signals and send confusing radar signals back to the source.
The original set of sensors also comprised an infrared sensor under the nose in a "chin pod": it was AN/ALR-23 with indium antimonide detectors, cooled by a self-contained Stirling cycle cryogenic system, but this proved ineffective, and was replaced with a new system. This was an optical system, Northrop AAX-1, also called TCS (TV Camera Set) and was used to help pilots visually identify and track aircraft, at least on day missions, up to a range of more than 60 miles (97 km) for large aircraft (a zoom function was included to help with small fighters). The TCS could be "slaved" to the radar to follow whatever the radar is tracking, and the radar could be slaved to the TCS to track whatever the camera "sees." Both the crew have access to the images on their displays. Despite its utility, for a long time most F-14s did not have the system added. Bill Gunston reported that even in 1983, only one in eight aircraft had the system fitted.
A dual IR/TCS system was adopted for the later F-14D variant, with an ECM antenna fitted as well in the same mast. This meant Tomcats could be configured with only an ECM antenna, or the IR sensor, or TCS, or many combinations thereof. The Tomcat's ESM system consists of many subsystems: RWR, ECM, and chaff/flare dispensers in various parts of the fuselage, nose, tail and wings. This was a marked difference with many previous fighter aircraft in that some did not even include a simple RWR.
Armament
The F-14 was designed to combat highly maneuverable aircraft as well as the Soviet cruise missile and bomber threats. The Tomcat was to be a platform for the AIM-54 Phoenix, but unlike the canceled F-111B, it could also engage medium and short range threats with other weapons. The F-14 was an air superiority fighter, not just a long-range interceptor. Over 6,700 kg (15,000 lb) of stores could be carried for combat missions on several hardpoints under the fuselage and under the wings. Commonly, this meant a maximum of two–four Phoenixes or Sparrows on the belly stations, two Phoenixes/Sparrows on the wing hardpoints, and two Sidewinders on the wing hardpoints. The F-14 was also fitted with an internal 20 mm M61 Vulcan Gatling-type cannon.
Operationally, the capability to hold up to six Phoenix missiles was never used, although early testing was conducted; there was never a threat requirement to engage six hostile targets simultaneously and the load was too heavy to recover aboard an aircraft carrier. During the height of Cold War operations in the late 1970s and 1980s, the typical weapon loadout on carrier-deployed F-14s was usually only one AIM-54 Phoenix, augmented by two AIM-9 Sidewinders, two AIM-7 Sparrow IIIs, a full loadout of 20 mm ammunition and two drop tanks. The Phoenix missile was used twice in combat by the US Navy, both over Iraq in 1999, but the missiles didn't score any kills.General characteristics
- Crew: 2 (Pilot and Radar Intercept Officer)
- Length: 62 ft 9 in (19.1 m)
- Wingspan:
- Spread: 64 ft (19.55 m)
- Swept: 38 ft (11.58 m)
- Height: 16 ft (4.88 m)
- Wing area: 565 ft² (54.5 m²)
- Airfoil: NACA 64A209.65 mod root, 64A208.91 mod tip
- Empty weight: 43,735 lb (19,838 kg)
- Loaded weight: 61,000 lb (27,700 kg)
- Max takeoff weight: 74,350 lb (33,720 kg)
- Powerplant: 2 × General Electric F110-GE-400 afterburning turbofans
- Dry thrust: 13,810 lbf (61.4 kN) each
- Thrust with afterburner: 27,800 lbf (123.7 kN) each
- Maximum fuel capacity: 16,200 lb internal; 20,000 lb with 2x 267 gallon external tanks
Performance
- Maximum speed: Mach 2.34 (1,544 mph, 2,485 km/h) at high altitude
- Combat radius: 500 nmi (575 mi, 926 km)
- Ferry range: 1,600 nmi (1,840 mi, 2,960 km)
- Service ceiling: 50,000 ft (15,200 m)
- Rate of climb: >45,000 ft/min (229 m/s)
- Wing loading: 113.4 lb/ft² (553.9 kg/m²)
- Thrust/weight: 0.91
Armament
- Guns: 1× 20 mm (0.787 in) M61 Vulcan 6-barreled gatling cannon, with 675 rounds
- Hardpoints: 10 total: 6× under-fuselage, 2× under nacelles and 2× on wing gloves with a capacity of 14,500 lb (6,600 kg) of ordnance and fuel tanks
- Missiles: ** Air-to-air missiles: AIM-54 Phoenix, AIM-7 Sparrow, AIM-9 Sidewinder
- Loading configurations:
- 2× AIM-9 + 6× AIM-54 (Rarely used due to weight stress on airframe)
- 2× AIM-9 + 2× AIM-54 + 3× AIM-7 (Most common load during Cold War era)
- 2× AIM-9 + 4× AIM-54 + 2× AIM-7
- 2× AIM-9 + 6× AIM-7
- 4× AIM-9 + 4× AIM-54
- 4× AIM-9 + 4× AIM-7
- Bombs: ** JDAM Precision-guided munition (PGMs)
- Paveway series of Laser guided bombs
- Mk 80 series of unguided iron bombs
- Mk 20 Rockeye II
- Others:
- Tactical Airborne Reconnaissance Pod System (TARPS)
- LANTIRN targeting pod
- 2× 267 USgal (1,010 l; 222 imp gal) drop tanks for extended range/loitering time
Avionics
- Hughes AN/APG-71 radar
- AN/ASN-130 INS, IRST, TCS
- Remotely Operated Video Enhanced Receiver (ROVER) upgrade
