The British Carrier Strike Fleet. David Hobbs
in developed form, on the NA 39. Difficulties were experienced with the fuze and the flip-out tail fins (it was carried on the aircraft in a tube with the fins retracted). Continuous development setbacks were encountered, not the least of which was the tendency of the missile to break up on entering the water. An assessment of Red Angel’s hitting probability in 1956 decided that from the optimum intended range of 5000 yards it would require a very large number of rockets to be fired at a cruiser-sized target30 to guarantee a hit and these would require an impractically large number of strike aircraft to carry them. Red Angel was, therefore, cancelled.
An even bigger anti-ship bomb was specified in another joint Naval/Air Staff requirement and developed under the codename ‘Green Cheese’. This was to be a rocket-powered bomb weighing 3300lbs at launch with a 1700lb warhead. It was to home onto radar reflections from the target which had, therefore, to be illuminated by the attacking aircraft’s radar throughout the missile’s time of flight until impact. Unsurprisingly, extensive sea trials found that target illumination against a cruiser-sized target was badly degraded by the sea clutter generated in seas associated with winds of Beaufort Scale 7. It was anticipated that the weapon would be carried by naval aircraft such as the Gannet and NA 39 at heights up to 18,000ft and released at a slant range of 10,000 yards from the target. RAF ‘V’-bombers were expected to use the weapon and release it from heights of 50,000ft to slant ranges of 20,000 yards.31 Despite high hopes, this weapon was also cancelled in 1956 because of ‘insufficient money and scientific effort to meet the requirement’. This left the RN with obsolescent 1000lb and 500lb bombs and 3in rockets as its principal conventional anti-ship weapons for the next two decades.
Air-to-air guided weapons were also the subject of a number of Naval/Air Staff requirements which called for both active radar-guided and passive infrared homing guided missiles. There were three radar-guided weapons, the earliest and simplest of which was the Fairey Fireflash, developed under the codename ‘Blue Sky’. It was a visually sighted, radar beam-riding missile intended for use by day fighters in clear weather. The missile itself was unpowered but accelerated off the launch rail by booster rockets; when these burnt out and detached the weapon slowed rapidly and had, therefore, to be fired at close range. It rode down the beam of the gun-ranging radar Mark 2 which was fitted in the RAF Hunter and the RN Scimitar so the nose of the fighter had to remain pointed at the target throughout the engagement. It was always seen as back-up for more advanced projects and, although development was completed by a joint RN/RAF trials party at RAF Valley in 1956, Blue Sky was never taken into operational service and the project was terminated.
‘Red Hawk’ was to be a radar-guided missile intended for carriage on high-speed fighters at heights up to 65,000ft and speeds up to Mach 2 giving the greatest possible tactical freedom to the launching aircraft before and after it was fired. From the RN perspective it was intended to break up massed attacks on the fleet by shore-based Soviet bomber regiments. Weapon aiming was to operate on a radar line of sight allied to a blind prediction sighting system and was to be possible by day or night under all weather conditions. Since Red Hawk was technically complex it was appreciated that its development would take a long time and so an interim version, codenamed ‘Red Dean’ was requested for use by RN and RAF all-weather fighters. This, too, was to be a radar-guided weapon but it was both large and heavy. RN interest was centred on the development of a missile with a maximum weight of 1500lbs; two missiles and their associated guidance system were expected to be installed in a developed version of the DH 110. By 1956 the missile’s designers, Vickers, had actually increased rather than reduced the missile’s weight and the Admiralty had, reluctantly, to withdraw from the joint project when it was appreciated that no naval aircraft in service or projected would be capable of carrying it.32 The Admiralty began to examine the possibility of obtaining other, more suitable, missiles that would give fighters full tactical freedom and selected the USN AIM-9A Sidewinder infrared-homing air-to-air missile for use on the Scimitar in 1957.
The most successful of the British joint missile projects was the de Havilland Firestreak, developed under the codename ‘Blue Jay’. A passive-infrared guided missile, it was intended for use in the DH 110 and P177 fighters as well as in a number of RAF aircraft projects. Its guidance system had the advantage that pilots could ‘fire and forget’ it and did not have to track the enemy aircraft after launch but the drawback was that its sensor had to lock onto the enemy’s heat signature, effectively the jet exhaust, which meant that the missile had to be fired in a cone-shaped area astern of the target at ranges between three and five miles. It had an expanding-ring warhead which cut through the target like a chainsaw as the missile passed close by the target, detonated by a sensitive fuze positioned aft of the sensor in the nose. It did not have to hit the target but, if it did, the kinetic energy of the impact would destroy most aircraft. An operational standard Firestreak hit and destroyed a drone target when first fired in 1956 and operational missiles went to sea with 893 NAS in Victorious during 1958. Firestreak entered service with a variety of training rounds; these including inert rounds for training magazine and weapons supply route handling parties and a practice acquisition round known as a PQR. This was a new concept intended to train aircrew in air-to-air acquisition and target tracking and it comprised the live sensor fitted into an inert missile with no motor or warhead which could be fitted to aircraft repeatedly. Apart from feeding information into the aircraft’s systems, it also fed a recorder which could be used shortly after every air combat training sortie by air warfare instructors (AWI) to debrief aircrew.
Work continued on two 18in air-dropped anti-submarine homing torpedoes throughout the early 1950s. The larger of the two was the 2000lb ‘Pentane’ which had a speed of 30 knots and a theoretical maximum range of 6000 yards. It was intended to have a minimum detection range of 1000 yards irrespective of target noise or speed and a maximum depth of 1000ft. Development was slow and the weapon was eventually overtaken by the procurement of lighter, more effective USN torpedoes which led to Pentane’s cancellation. ‘Dealer B’, the lighter weapon, proved more successful and was introduced into service as the Mark 30 in 1954 for use in the Gannet AS 1 and, eventually, the Whirlwind HAS 7 helicopter. It was an electrically-powered, passive acoustic homing torpedo with a length of 8ft 6in and a range of 6000 yards at 12.5 knots. Weight was only 670lb with the air tail and parachute units, intended to keep the weapon stable after release from the aircraft before it hit the water, fitted making it considerably more practical than Pentane, it had a maximum diving depth of 800ft and could be released from aircraft flying at over 300ft at speeds up to 300 knots.
On entering the water the flight in air material detached and the Mark 30 sank to a depth of 20ftbefore activating. It than set up a circular search pattern a depth of 30ft until detecting the sound of a submarine. Trials indicated a homing radius of 600 yards against an ‘S’ class submarine moving at 5 knots but the exact radius depended on the radiated noise caused by target speed.33 When a sufficiently strong signal was detected the weapon automatically increased speed to 19.5 knots.34 To avoid a stern chase developing, a small ‘cone of silence’ was built into the acoustic sensor in the centre of the torpedo’s nose; this established a ‘lead angle’ whilst maintaining contact and caused the weapon to aim slightly ahead of the target until the last seconds. As a passive weapon, it also had the advantage that it could not be detected until it was in the water and actually homing on its intended target. Depth charges and rockets remained the weapons of choice for use against surfaced or snorting submarines.
The development of mines continued for some years after the Second World War and by 1954 a number of different new types were in service. These included the A Mark 12 which had ‘boxed assemblies’ which allowed the firing system to be changed on board a carrier, doing away with the need to embark specialised mines for individual operations. The A Mark 10 was a moored mine intended for use against minesweepers and was to be interspersed with ground mines.
Avionics
As weapons and their tactical use became more complicated in the mid-1950s, aircraft systems also became more expensive and complicated. The gyro rocket bomb sight and naval strike sight intended for use on the Wyvern and NA 39 for use with Red Angel and Green Cheese were given high priority in 1952 but eventually cancelled with those projects. Work on radar ranging for the gyro gun sight continued and was fitted in the Scimitar from 1957. Work started in 1954