Sea Eagle Background
Though the 'Anglo-French' Martel missile had only entered operational service with the RAF in 1972 and the Royal Navy in late 1973, the British were already envisaging the 'Next Generation' anti-ship missile to replace it. The Martel had proved itself to be a very efficient 'Guided-Weapons' system, but in the case of the 'Anti-Ship' (AJ.168) 'TV' version, there were three major limitations:
It's medium altitude approach to target.
Each aircraft could only fire one missile at a time because the system relied on operator tracking from the delivery aircraft.
An effective operational range of approximately 12 miles (max. 33 miles).
In 1973, the development project was allocated the designation 'P3T'. The basis of the new missile design would capitalise on the successful 'Active Radar' Martel project.
In 1976, BAe Dynamics started the initial design work and a provisional development contract was begun in 1977, culminating in full-scale development in 1979.
One major difference in the two types of missile systems, was the method of propulsion. In the 'Martel' design both the AS.37 'Anti-Radar' and AJ.168 'Anti-Ship' missile were powered by boost-sustain solid rocket motors (two-stage solid propellant rocket motors - 2.4s boost, 22.2s sustain). In the case of this next generation 'P3T' missile, this would be powered by a Microturbo TRI-60 turbojet which develops around 787lb of Static Thrust. The intake for the turbojet is mounted on the underside of the missile between the two main lower fins. This is protected from ingress of foreign matter during transit by an aerodynamic fairing, which is jettisoned at launch. Another major difference was a dramatic increase in operational range to 60 miles compared to only 12 miles of the AJ.168 Martel (ASM) missile.
Buccaneer S.Mk.2's were used for the 'Weapons Trials' of the missile:
XK527 was used for 'Carriage & Flutter' tests in 1981.
In 1982, construction of production missiles began:
XW529 was the 'Primary' weapons test aircraft.
XV350 was the 'Secondary' test aircraft.
BAe Dynamics - Sea Eagle 'Anti-Ship' Missile
In 1984, full 'Evaluation Trials' were completed and the 'P3T' missile was formally named as the Sea Eagle 'Anti-Ship' missile.
The Sea Eagle is a completely autonomous missile following launch. Once the Buccaneer's navigator has aquired a target, the information is sent to the missile prior to it's release. On launch the missile drops to sea-skimming height of only 10ft!, using a 'Radar Altimeter' and a directional 'Inertial Navigation System' (INS) to control it's tragectory.
The Sea Eagle is a true 'Fire-and-Forget' weapon.
When the missile has estimated that it had penetrated the radar horizon of the designated target vessel, the 'I-Band Active Homing Head' switches on and the missile begins to climb - until this moment the system has remained totally silent. As soon as the target is selected, the missile returns to it's sea-skimming profile, to eventually hit the target vessel at only 10ft above the water line. It is armed with a 506lb 'Semi-Armour Piercing' (SAP), impact delay-fused penetrating 'Blast Fragmentation' warhead, capable of penetrating up to six bulkheads of a modern warship.
From the outset, the Sea Eagle was designed to operate in an 'Electronic Counter-Measures' (ECM) environment and even has the capability to locate and 'Lock-On' to a specific vessel within a target group. It's onboard computer has a programmable guidance system providing for a large choice of cruise, search, and attack options.
Because of the Sea Eagle's long range capability, this enabled the Buccaneer a covert approach to it's designated target and the ability to leave the area once the missiles had been fired without ever being seen by the enemy vessel.
Following the upgrade of the Buccaneer S.Mk.2 to carry the Martel missiles, it's replacement by the Sea Eagle meant no reduction in weapons load capability. In fact, as the missile did not require a 'Data Link Pod', the Buccaneer was able to carry a full compliment of 'Four' Sea Eagles, compared to only three 'TV' (AJ.168) Martel missiles. Also, each Sea Eagle can receive a pre-designated target prior to launch, enabling a salvo of four missiles to be fired at the same time, hence allowing immediate egress from the area by the Buccaneer.
A typical maritime attack would consist of 'Six' Buccaneers, split into two formations of three aircraft, each armed with a full compliment of Sea Eagles - giving a 24 missile strike capablity.
The two formations would be initially flying at 100ft over the sea and thanks to the associated 'Avionics Upgrade Programme' ASR 1012, could carry out a coordinated attack from up to 40 miles apart, from multiple axes and enable a multiple missile strike of 24 Sea Eagles within a ten second 'Window'.
It's attack profile, flying at only 10ft above the surface of the sea, means that it is near-impossible to engage and a 24 missile salvo guaranteed to succeed. Also, the Sea Eagle's autonomous nature means that it is in it's element as a night attack weapon.
If attacking a Surface Attack Group (SAG) comprising a number of warships, the Buccaneers would have gone in silent. However they could receive information via a secure link from Nimrod or AWAC aircraft, which would update them of the SAG location and formation. Individual Sea Eagle missiles could then be programmed to attack specific ships -- nearest, furthest, largest etc. During the attack run, when the Sea Eagle did it's pop up, it would identify it's target then go back to 10ft and home in on it's target. Sea Eagle could fly around other ships to get to its selected target.
An initial programme of 10 Buccaneer aircraft were converted to Sea Eagle capability between December 1984 and April 1986, followed by a further 10 aircraft between April 1985 and September 1986, as an integral part of the 'Avionics Upgrade Programme' ASR 1012.
208 Sqn., RAF Lossiemouth became the first fully operational Sea Eagle 'Maritime Strike' squadron by the end of 1986, followed by 12 Sqn. RAF Lossiemouth during 1988. The missile system became the permanent 'Anti-Ship' missile throughout the remaining service life of the Buccaneer, until the aircraft type's retirement on 31st March 1994.
|Source -||Buccaneer: The story of the last all-British strike aircraft (Tim Laming)
The Buccaneers (Air Commodore Graham Pitchfork)
Wings of Fame - volume 14 (Aerospace Publishing Ltd)
RAF Buccaneer (Peter Foster)
(see Reference Library page for full details)
|Additional Info. -||John Robertson (Electronic Engineering Technician)
12, 15, Squadron, 237 OCU and Buccaneer/Jaguar Maintenance School
Guided Weapons United Kingdom Aerospace and Weapons Projects
[8.7] Antiship Missiles (1) Greg Goebel / In The Public Domain