Bofors Anti-Aircraft Gun

A collection of images of a Bofors anti-aircraft gun taken on the grounds at Caldicot Castle.

All photos were taken on May 6th 2017
Photos: Tony Wilkins

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British Army Bayonet Training Manual, 1916

The following extracts are taken from a US-produced reproduction of the British Army’s Bayonet Training Manual revised in 1916 to take in to consideration the nature of the fighting on the Western Front of World War I. With the US declaring war on Germany and the other Central Powers on January 9th 1917, they looked to take advantage of the lessons the Allied powers had learned in the previous two and a half years and apply them to their own troops.


Weapon File: Red Top

Final Red TopThe De Havilland Red Top was an infra-red guided air-to-air missile and was the successor to the earlier Firestreak. Often viewed as merely an upgraded Firestreak the Red Top is in fact a far more potent and mature weapon.

Development of Red Top began under the codename Blue Jay Mk.4 before being re-designated Firestreak IV for operational use. However, De Havilland argued that the changes to the weapon were so dramatic that a new name should be selected and therefore it was named Red Top to distinguish it from its forebear. Whereas the Firestreak looked like something out of a 1930s Flash Gordon serial the new missile was more modern yet menacing to look at. It was certainly larger being a noticeable 13cm longer and weighing an extra 40lbs and having redesigned wings of greater span but it was inside the weapon that made the greatest difference.

red topIn developing Red Top the De Havilland team completely reassessed the layout of the Firestreak. One of the more unusual decisions taken in building the original weapon was to place the warhead in the tail of the missile around the motor. Not only did this limit the size of the warhead but it also limited its effectiveness upon impact. In Red Top the warhead was placed behind the seeker assembly in the nose and consisted of 68lbs (compared to Firestreak’s 50lbs) of explosive triggered by a proximity detonator. Like Firestreak the new weapon was controlled by four guidance fins at the rear that gave it excellent agility.

Guidance for the weapon was provided by the Violet Banner infra-red seeker. For the early 1960s this was a very sophisticated scanner and was one of the first infra-red missiles to introduce a cooling system in the seeker head to improve the infra-red image of the target. In all infra-red guided missiles (and even infra-red cameras) background heat from inside the sensor such as that generated by the hot electronic equipment or the heat built up on the seeker’s window as a result of friction as the missile flies though the air can overpower the comparatively weak signal of the target. Cooling the seeker head therefore clears up the infra-red image of the target and dramatically increases sensitivity.

Red Top missileThis led to a general belief that Red Top was the world’s first all-aspect infra-red air-to-air missile however this is not entirely true. Red Top could only engage targets from the front that were travelling at supersonic speeds thanks to the target developing a rather large heat plume from its engines and the friction-heating of the fuselage at high speeds. For targets travelling at subsonic speed then a more traditional rear-hemisphere attack was required. An often cited problem with the seeker however was that cloud inhibited its effectiveness in tracking a target but it is important to note that this was a common problem with all infra-red weapons of the day. While this would potentially be a drawback fighting tactical aircraft at low to medium altitude it remained a very effective weapon intercepting high altitude bombers where there was little cloud. The seeker was aided by the launch aircraft’s own radar which can transmit the location of the target to the missile while its on the rail so that the seeker is looking directly at the target upon launch.

hawker_seavixenRed Top was cleared for service in 1964 and armed the RAF’s English Electric Lightning F.3/6 and the Royal Navy’s De Havilland Sea Vixen FAW.2 (right). While the Gloster Javelin was armed with the earlier Firestreak plans to equip it with Red Top were shelved due to the aircraft’s impending retirement. Of the two aircraft that carried Red Top operationally the Sea Vixen was arguably the better platform for the weapon having a second crewman who could plot and prosecute the target more efficiently without having to fly the aircraft as well. The Sea Vixen could carry up to four weapons whereas the Lightning could only carry two (theoretically the Lightning could carry four weapons but plans for additional weapons to be carried under the wing pylons for export aircraft never materialised).

Lightning Red TopHowever the Lightning’s own performance actually increased the performance envelope of the missile. When flying at speeds in excess of Mach.1 at the Lightning’s service ceiling of 54,000ft the Red Top could generate enough energy to reach an altitude in excess of 70,000ft. The Lightning’s supersonic speed also increased range and reports from testing claim the weapon flying out to a head-on target range of 7-8 miles (when in the chase position this range will decrease as the target is moving away and so the weapon has to overtake it). Carrying the quite heavy weapon did impose restrictions on the light and aerodynamically pure Lightning and pilot notes for the Lightning F.6 model dictated that whilst armed the aircraft should not fly passed Mach 1.75 so as to not overstress the airframe.

Any infra-red air-to-air missile developed in the 1960s will ultimately be compared to the US AIM-9 Sidewinder family. Compared to the AIM-9B Sidewinder, Red Top was a far superior weapon with a more sophisticated seeker, longer range, greater agility and a substantially more powerful warhead. The AIM-9B also had a very limiting launch load factor of just 2.6G whereas Red Top could be fired at up to 4G making Red Top the better weapon in a dogfight. The only real advantage the AIM-9B had was that it was much lighter weighing just 180lbs compared to Red Top which weighed in at nearly 340lbs and could be more easily integrated on to a wider array of aircraft. This latter fact was the key to its export success compared to most other air-to-air weapons of the era including Firestreak and Red Top. When you consider that the primary Soviet close-in air-to-air missile for the 1960s and 70s was the AA-2 “Atoll”, a reverse engineered AIM-9B, then it can be claimed that Red Top was better than this weapon also.

Red Top & AIM-9B SidewinderThe AIM-9B’s extremely poor showing over Vietnam forced rapid development of an improved model, the AIM-9D Sidewinder and this had advantages and disadvantages when compared to Red Top. The AIM-9D had a marginally longer head-on range compared to Red Top again dependant on the conditions at launch. Red Top still had the more sensitive seeker and its larger window gave it a better view of the world outside. Also Red Top’s larger warhead meant that it was more likely to destroy whatever it hit or inflict fatal damage with a proximity hit. It’s interesting to note however that when the Royal Navy selected McDonnell Douglas’ F-4 Phantom II in its Anglicized F-4K Phantom FG.1 form both Red Top and AIM-9D were tested against each other. The Admiralty decided to keep the AIM-9D as the aircraft’s primary close-in weapon despite Red Top already being supported in service with the Sea Vixen. The main reason cited for this was to simplify the introduction of the already overly complex British Phantom to squadron service.

Consequently, Red Top was withdrawn from Royal Navy service in 1972 when the Sea Vixens were retired leaving the Sidewinder armed Phantoms as the Fleet Air Arm’s primary fighter. Red Top continued to arm the RAF’s Lightnings until 1988 and in July of that year the very last live round was fired over Cardigan Bay, South Wales (see top image).

  • Wingspan : 0.91 metres (2.95ft)
  • Length : 3.32 metres (10.89ft)
  • Body Diameter : 0.23 metres (0.75ft)
  • Weight : 154 kilograms (340lbs)
  • Warhead : 31 kg (68.3 lb)
  • Speed : Mach 3.2 (2436 mph)
  • Range : 7.5 miles
  • Service Ceiling : 70,000+
  • Launch Load Factor : 4G

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Nuclear Weapons

Operation: Hurricane Atomic Bomb

Operation Hurricane BombThe Operation: Hurricane atomic bomb was Britian’s first nuclear weapon. Development of the project began following a secret cabinet meeting of the British government in 1946 after the US passed the McMahon Atomic Energy Act of 1946 which barred the British and anyone else from gaining access to nuclear test data from the Manhattan Project despite Britain contributing its own scientists to the development of the American program. These scientists would ultimately work on the British bomb which received the codename “Hurricane”. As a result the weapon greatly resembled the American “Fat Man” weapon which was dropped on Nagasaki.

The design of the weapon incorporated a hollow core consisting of 7kg of plutonium. There were other designs planned including the use of Canadian manufactured plutonium for a Canadian nuclear weapon program. The Canadians, like Britain, had contributed scientists to the Manhattan Project and now felt shut out by the US who seemed determined to hold a monopoly on nuclear weapons. However only the British 7kg core design was used in the test.

The weapon was ready for testing in 1952 by which time the Americans had lost their nuclear monopoly to the Russians who detonated their first weapon in 1949. Working in conjunction with the Australian government, who were the only British Commonwealth country with the vast expanses of territory needed for safe testing, the islands of Monte Bello off the north west coast of Australia was selected as the test site. Instead of being dropped by an aircraft or on a fixed land platform it was instead placed inside a decommissioned River-class frigate, HMS Pym. Reports claim that at the time there was a very real belief by British intelligence that any pre-emptive attack from the Communist block would begin with suicide ships being charged into major naval installations with a nuclear weapon onboard,

The test was carried out on the 3rd October 1952 and catapulted Britain (and by association Australia and Canada) in to the nuclear age becoming the third nuclear power. The blast was 25 kilotons in power and left a saucer-shaped crater on the seabed 20ft deep and 980ft across. The test results were used to develop more effective nuclear weapons in the future that included American made warheads after the US amended the McMahon Atomic Energy Act in order to promote commercial nuclear development and better equip its allies in the face of an increasingly powerful nuclear Soviet Union.

Op Hurricane 25kt

Effect of a 25 kiloton nuclear weapon detonated in the centre of London (

Weapon File: Sea Eagle


Sea Eagle was an anti-ship missile fielded initially by Royal Air Force (RAF) Blackburn Buccaneer S.2Bs and Royal Navy Sea Harrier FRS.1s. It was later carried by the Panavia Tornado GR.1B when the Buccaneer was withdrawn from service and was exported to India who carried it on their own Sea Harrier FRS.51s, Sea King helicopters and Il-38 ‘May’ maritime patrol planes.

Sea Eagle was developed from the earlier Martel missile which was developed jointly by a consortium of UK and French companies in both TV-guided and Anti-Radar Missile (ARM) versions. The TV-guided version was utilized by the RAF for the anti-ship role but it was soon realized a more dedicated weapon was needed. Using Martel as a basis, the “P3T” was to be turbojet powered as opposed to a solid fuel rocket as in the Martel to increase range. Guidance was to come from an onboard inertial navigation system with information provided by the launch aircraft and an active radar seeker for the terminal phase.

The “P3T” became Sea Eagle and after a series of successful test firings in 1984 the weapon entered service with the RAF and Royal Navy the following year. A ship launched version was developed for use by surface warships using two strap on boosters for the launch to get the weapon up to a speed where it’s turbojet engine could kick in. Although it never entered service the system became the basis for the helicopter version which needed the boosters to achieve it’s launch speed. A land attack version was also proposed but was not followed through.
SeaHarrierandSeaEagleThe Sea Eagle was intended to operate against the Soviet Navy’s surface force operating in the North Atlantic and the Greenland-Iceland-UK (GRIUK) gap. It’s 510lb warhead was sufficient to mortally damage some of the smaller Soviet ships such as the widely exported Grisha-class and force some of the larger vessels out of the fight. It also had sufficient range to keep the launch aircraft out range of all but the longest ranged Soviet naval defences.

Both Tornado and Buccaneer could carry four missiles comfortably but two with external fuel tanks for extended range was the normal loadout. The Sea Harrier on the other hand could only carry two maximum along with two AIM-9L Sidewinders for defence against enemy aircraft. This seriously reduced the aircraft’s operational range from the aircraft carrier limiting its use as an offensive weapon but it was still a potent aircraft/weapon combination in any major surface engagement between an RN task group and an opposing surface force.

Sea Eagle remained in the British arsenal until the late 1990s when it was withdrawn following the decision to take the maritime strike role away from the Tornado (hence no Tornado GR.1Bs became GR.4Bs during the mid-life update). Initially it was believed the weapon had become obsolete but it was later admitted that the weapon was withdrawn purely as a cost-cutting measure because in the eyes of the MoD there was no longer a substantial naval surface threat to the UK. The weapon remains in service with the Indian Air Force and Navy who use it on a variety of platforms including, ironically some would say, their force of mighty Tu-142 “Bear” maritime patrol bombers.

  • Wingspan : 1.2 metres (3 feet 11 inches)
  • Length : 4.14 metres (13 feet 7 inches)
  • Body Diameter : 0.4 metres (1 foot 4 inches)
  • Weight : 580 kilograms (1,279 pounds)
  • Warhead : 230 kilograms (510 pounds) of PBX (semi armour-piercing)
  • Speed : Mach 0.85 (645 mph)
  • Range : 110 kilometres (68 miles / 60 nautical miles) plus
  • Flight time : 400 seconds (6 min 40 seconds)