Phoenix Credit - via Andreas Parsch

Historical Essay © Andreas Parsch

Raytheon (Hughes) AAM-N-11/AIM-54 Phoenix

The AIM-54 Phoenix is the only long-range air-to-air missile currently in service with the U.S. armed forces, and is exclusively used by the U.S. Navy's F-14 Tomcat fighters.

Development of the Phoenix began in late 1960, after the U.S. Navy's projected F6D Missileer and the associated AAM-N-10 Eagle long-range interception missile had been cancelled. Hughes then started to develop a new long-range missile, designated AAM-N-11 by the Navy, together with the AN/AWG-9 FCS (Fire Control System). The new missile and FCS used technology previously tested by the AIM-47 Falcon and AN/ASG-18, respectively, in the USAF's YF-12A program. The Phoenix/AWG-9 combination was originally intended as the main armament for the F-111B, then planned to become the Navy's new air superiority fighter and long-range interceptor. In June 1963, the AAM-N-11 was redesignated as AIM-54A. Flight tests of XAIM-54A prototypes began in 1965, and the first guided interception succeeded in September 1966. While the Phoenix test program continued, the F-111B was cancelled, and the AIM-54 and AN/AWG-9 were incorporated into the new F-14 Tomcat, which was to take over the role of the F-111B. The first production AIM-54A missiles were delivered in 1973, ready for deployment with the first F-14A squadron in 1974.

An F-14 can carry up to 6 Phoenix missiles, on LAU-93/A (F-14A/B) or LAU-132/A (F-14D) launchers, respectively. The AN/AWG-9 FCS uses a TWS (Track While Scan) pulse-doppler radar, and can track up to 24 targets simultaneously at ranges of up to 240 km (130 nm). Therefore, an F-14 can effectively attack 6 targets simultaneously. When an AIM-54A is launched, its Rocketdyne MK 47 or Aerojet MK 60 solid-fueled rocket motor (in an MXU-637/B propulsion section) propels it to a speed of Mach 4+. For mid-course guidance, the missile's AN/DSQ-26 guidance section employs an autopilot, which gets regular target position updates by semi-active radar tracking. The FCS radar periodically illuminates every target to which a missile has been dispatched. For maximum range, the missile flies an optimized high-altitude trajectory for reduced drag, and the AIM-54A can engage head-on targets at a distance of up to 135 km (72.5 nm). For the final 18200 m (20000 yds) of the interception, the Phoenix switches to active radar homing for high terminal accuracy. Minimum engagement range is about 3.7 km (2 nm), in which case active homing is used from the beginning. The 60 kg (132 lb) MK 82 blast-fragmentation warhead is detonated by a fuzing system consisting of a MK 334 radar proximity, an IR proximity, and an impact fuze.

There are several non-tactical variants of the AIM-54A. The ATM-54A is a version with inert warhead for firing exercises, the CATM-54A is the captive (non-launching) version for target acquisition practice, and the DATM-54A is a completely inert dummy missile for ground handling training. The AEM-54A is a variant with special telemetry electronics for test and evaluation purposes.

The designation AIM-54B refers to an AIM-54A modified for easier production, including sheet metal instead of honeycomb structure in the wings and fins. Some sources say that the AIM-54B was produced from 1977, while others say it wasn't built in quantity. The latter seems plausible, because although the U.S. Navy still lists many AIM-54As in its inventory, it doesn't mention any AIM-54Bs. Another possibility is that the AIM-54B was redesignated as a subvariant of the AIM-54A, because it was operationally identical to the latter. The designations ATM-54B and AEM-54B were, formally at least, allocated to training and telemetry versions of the AIM-54B, respectively.

In 1977, development of the significantly improved AIM-54C began. The AIM-54C features completely new digital WGU-11/B guidance and WCU-7/B control sections. The missile incorporates a programmable digital signal processor, and the autopilot now uses a strap-down inertial navigation system. One very important feature of the AIM-54C is its vastly improved ECCM capability. Improvements in the rocket motor increase speed and range, and the new DSU-28/B target detection device improves fuzing accuracy in high-clutter environments and for small and low-altitude targets. The first XAIM-54C prototypes were delivered in August 1979, and after tests with YAIM-54C missiles, production of the Phoenix switched to the AIM-54C in 1982. Initial Operational Capability of the AIM-54C was reached in 1986. Non-tactical variants include the ATM-54C for firing exercises, the CATM-54C captive (non-launching) version for target acquisition practice, and the AEM-54C with special telemetry electronics for test and evaluation purposes. There is no DATM-54C, because the DATM-54A is also suitable for AIM-54C ground handling training.

The AIM-54C was continually upgraded during production. Early in the production run, the MK 82 warhead was replaced by a new WDU-29/B warhead in a WAU-16/B or WAU-20/B warhead section. The WDU-29/B offers a 20 to 25 percent increase in effectiveness. Another improvement was the addition of internal temperature compensation, which eliminated the need for the F-14 to provide temperature compensation liquid during captured flight. Missiles with this feature, first delivered in 1986, are called "sealed", and are sometimes referred to as AIM-54C+. During the production, the ECCM capabilities were still further improved, and "sealed" AIM-54C missiles with improved ECCM are known in the U.S. Navy as AIM-54C ECCM/Sealed. This variant reached IOC in 1988. The guidance and control sections of the ECCM/Sealed missile are the WGU-17/B and WCU-12/B, respectively, and the available warhead sections are the WAU-19/B and WAU-21/B. Other improvements, which can be retrofitted to older AIM-54C rounds, include a reprogrammable memory, and new software for the signal processor.

When production ceased in the early 1990s, more than 5000 AIM-54 missiles of all versions had been built, about half of these being AIM-54Cs. Because the Phoenix is used only by the F-14 Tomcat, it will remain in service as long as this aircraft, and the F-14 will be phased out by 2010 approximately. All operational Phoenix missiles are now of the AIM-54C variant, and the remaining AIM-54As have been placed in storage. The AIM-54 was primarily designed for long-range fleet defense against incoming bomber streams, a threat which has dimished nowadays. Although it can theoretically also be used against low-flying high-speed anti-ship missiles, there are more effective weapons for this role. Currently, there are no plans to field any other missile with Phoenix-like performance characteristics when the AIM-54 is retired.

Note: Data given by several sources show slight variations. Figures given below may therefore be inaccurate!

Data for AIM-54A/C:

[1] Norman Friedman: "US Naval Weapons", Conway Maritime Press, 1983
[2] Norman Friedman: "World Naval Weapons Systems, 1997/98", Naval Institute Press, 1997
[3] Bill Gunston: "The Illustrated Encyclopedia of Rockets and Missiles", Salamander Books Ltd, 1979
[4] Christopher Chant: "World Encyclopaedia of Modern Air Weapons", Patrick Stephens Ltd., 1988
[5] Hajime Ozu: "Missile 2000 - Reference Guide to World Missile Systems", Shinkigensha, 2000
[6] Bernard Blake (ed.): "Jane's Weapon Systems 1987-88", Jane's, 1988

Manufacturer: Hughes. Guidance contractor: Raytheon.

For use on F-14A/D. Semi-active / active- radar-guided.

Manufacturer: Hughes. Location: Tucson, AZ, USA. Guidance contractor: Raytheon. Total Mass: 447 kg (985 lb). Core Diameter: 0.38 m (1.24 ft). Total Length: 3.96 m (12.99 ft). Span: 0.91 m (2.98 ft). Standard warhead mass: 60 kg (132 lb). Maximum range: 141 km (87 mi). Boost Propulsion: Solid rocket. Boost engine: Mk. 47 Mod 0. Guidance: Semi-Active + Active Radar Homing. Maximum speed: 5,650 kph (3,510 mph). Ceiling: 24,400 m (80,000 ft). Floor: 15 m (49 ft). Development Cost $: 166.000 million. in: 1982 average dollars. Recurring Price $: 0.412 million. Total Number Built: 2285. Flyaway Unit Cost $: 0.432 million. in: 1982 unit dollars.

Semi-active / active- radar-guided

Manufacturer: Hughes.

Manufacturer: Hughes. Total Mass: 462 kg (1,018 lb). Core Diameter: 0.38 m (1.24 ft). Total Length: 4.30 m (14.10 ft). Span: 0.92 m (3.01 ft). Standard warhead mass: 61 kg (134 lb). Maximum range: 519 km (322 mi). Boost Propulsion: Solid rocket. Boost engine: Mk. 47 Mod 0. Guidance: Active Radar Homing. Maximum speed: 4,520 kph (2,800 mph). Ceiling: 24,700 m (81,000 ft). Floor: 15 m (49 ft). Development Cost $: 167.800 million. in: 1982 average dollars. Recurring Price $: 1.298 million. Total Number Built: 810. Flyaway Unit Cost $: 1.343 million. in: 1982 unit dollars.

Solid-state electronics.

Manufacturer: Raytheon Co., Raytheon Systems Co., Defense Systems. Location: Tucson, AZ, USA. Guidance contractor: Raytheon. Core Diameter: 0.40 m (1.30 ft). Total Length: 3.96 m (13.00 ft). Span: 0.92 m (3.00 ft). Boost Propulsion: Solid rocket. Boost engine: Mk. 36 Mod 6. Guidance: Semi-Active + Active Radar Homing.