The Battle of the Beams was a period in early World War II when Luftwaffe bombers started using radio navigation for night bombing. British "scientific intelligence" at the Air Ministry fought back with a variety of increasingly effective means, and the Germans eventually gave up trying to use any such system. Combatants Allied powers: China France Great Britain Soviet Union United States and others Axis powers: Germany Italy Japan and others Commanders Chiang Kai-shek Charles de Gaulle Winston Churchill Joseph Stalin Franklin Roosevelt Adolf Hitler Benito Mussolini Hideki Tōjō Casualties Military dead: 17,000,000 Civilian dead: 33,000... This does not adequately cite its references or sources. ... Radio navigation is the application of radio frequencies to determining a position on the earth. ... The Air Ministry was formerly a department of the United Kingdom Government, established in 1918 with the responsibility of managing the affairs of the (then newly formed) Royal Air Force. ...

Background

Both the British and Germans based much of their pre-war bombing strategy on night bombing, in which the threats to the bombers from fighter interception and ground-based anti-aircraft systems were greatly reduced. However, the disadvantage of this strategy was the difficulty of finding a blacked-out target at night. A bomber is a military aircraft designed to attack ground targets, primarily by dropping boobs. ... American troops man an anti-aircraft gun near the Algerian coastline in 1943 Anti-aircraft, or air defense, is any method of combating military aircraft from the ground. ... This article or section does not adequately cite its references or sources. ...

The RAF thus invested very heavily in navigation training, equipping their aircraft with various equipment for taking a star fix and giving the navigator room to do calculations in a lit workspace. They put this system into use as soon as the war began and were initially happy with its success. In reality the bombing effort was a complete failure, with the vast majority of bombs landing miles away from their intended targets. The Royal Air Force (RAF) is the air force branch of the British Armed Forces. ... Celestial Navigation is the 15th episode of The West Wing. ...

The Luftwaffe instead invested heavily in radio navigation systems to solve the same problem. They already had some experience with these sorts of systems due to their deployment of the Lorenz blind-landing aid at many airports, which also equipped most of their bombers in order to allow them to land at night or in bad weather. Radio navigation is the application of radio frequencies to determining a position on the earth. ... Prior to the World War II the Germans had deployed the Lorenz blind-landing aid at many airports and equipped most of their bombers with the radio equipment needed to use it. ...

The Lorenz system worked by feeding a special three-element antenna system with a modulated radio signal. The signal was fed to two of the elements at any given time, producing a fairly directional signal from the resulting dipole that was pointed off the end of the runway. A special switch rapidly selected between the two pairs of dipoles (the center element being used in common), sending the signal briefly out of one of the pairs and then for a longer time out of the other, resulting in a "dot" or "dash" signal on the left or right of the runway centerline, respectively. On the relatively narrow center line, the dashes exactly filled the gaps between the dots such that a continuous equisignal was received. Lorenz could fly a plane down a straight line with relatively high accuracy, enough so that the aircraft could then find the runway visually in all but the worst conditions.

The Luftwaffe concentrated on developing a bombing direction system based on the Lorenz concept through the 1930s, as it made night navigation relatively easy by simply listening for signals on a radio set, and the needed radios were already being installed on many aircraft. Lorenz directed an aircraft down a line, so two Lorenz-like systems with crossed beams could be used to fix a single spot. All that would be needed was a second Lorenz receiver.

Lorenz had a range of about 30 miles, enough for blind-landing but not good enough for bombing raids over England. This could be addressed by using more powerful transmitters. In addition the beams of Lorenz were deliberately set wide enough that they could be easily picked up at some distance from the runway centerline, but this meant their accuracy at long ranges was fairly limited. This was not a problem for blind landing, where the distance covered by the fan-shaped beams decreased as the airplane approached the transmitters, but for use in the bombing role this would be reversed, and the system would have maximum inaccuracy over the target. To address this all that was needed was to make a much larger antenna array.

German systems

Knickebein

Main article: Knickebein (navigation)

For bombing use the modifications to Lorenz were fairly minor. Much larger antennas with considerably smaller beam angles were set up, and broadcast power was increased considerably. The first two of these new Knickebein ("crooked leg") transmitters were set up at Stollberg in northern Germany near the border with Denmark, and the other at Kleve (Cleves), almost the most westerly point in Germany. The two aerials could be rotated to make the two beams cross over the target. The bombers would fly into the beam of one and ride it until they started hearing the tones from the other (on the second receiver). When the steady "on course" sound was heard from the second beam, they dropped their bombs. Knickebein (crooked leg in German, but also the name of a magic raven in a German fairy tale) was a radio navigation system used by the Luftwaffe early in World War II to aid bomber navigation. ... Knickebein (crooked leg in German, but also the name of a magic raven in a German fairy tale) was a radio navigation system used by the Luftwaffe early in World War II to aid bomber navigation. ... Kleve (occasionally referred to in English as Cleves) is a city in the north-west of North Rhine-Westphalia in Germany, near the Dutch border and the river Rhine, at . ...

It was the shape of the aerials that gave the system its code name. Unlike the wide-pattern Lorenz, Knickebein required far more accuracy. This was achieved by using aerials with many more elements, but it retained the simple switching of the two dipoles to alter the beam directions very marginally.

The Knickebein receivers were disguised as a standard blind landing receiver system, consisting apparently of the EBL-1 and the EBL-2 blind landing receivers. The sensitivity of the receivers though had been considerably enhanced from the standard equipment in the hope that the British wouldn't appreciate their purpose. Information overheard from captured aircrew revealed that the aircrew believed that the British would never find it (indicating that the equipment was on board the aircraft). In the event, the Royal Aircraft Establishment at Farnborough realised that the equipment was far more sensitive than it needed to be for a standard blind landing receiver. Knickebein was codenamed "Headache". This article needs cleanup. ...

Knickebein was used in the early stages of the German night-bombing offensive, and proved to be fairly effective. However the tactics for using the system in a widespread bombing effort were not yet developed, so much of the early German night bombing offensive was limited to area bombing anyway.

Efforts in England to stop the system took some time to get started. British intelligence at the Air Ministry, led by R V Jones, were aware of the system initially because a downed German bomber's Lorenz system was analysed and seen to be far too sensitive to be a mere landing aid. Also secretly recorded transcripts from German POW pilots indicated this may have been a bomb aiming aid. Winston Churchill had also been given Ultra (intelligence from Enigma messages) mentioning 'bombing beams'. Professor R V Jones Reginald Victor Jones (29 September 1911 – 17 December 1997) was an English physicist and scientific military intelligence expert who played an invaluable role in the defence of Britain in World War II. // Biography Born in Dulwich, Jones was educated at Alleyns School, Dulwich and Wadham... Churchill redirects here. ... Ultra (sometimes capitalized ULTRA) was the name used by the British for intelligence resulting from decryption of German communications in World War II. The term eventually became the standard designation in both Britain and the United States for all intelligence from high-level cryptanalytic sources. ... The plugboard, keyboard, lamps and finger-wheels of the rotors emerging from the inner lid of a three-rotor German military Enigma machine (version with labels) In the history of cryptography, the Enigma was a cipher machine used to encrypt and decrypt secret messages. ...

When Jones mentioned the possibility of bombing beams to Churchill, Churchill put two and two together and ordered more investigation. However, many in the Air Ministry didn't believe that the system was actually in use, and Frederick Lindemann, leading scientific adviser to the government, claimed that any such system would not be able to follow the curvature of the Earth, though T S Eckersley of the Marconi company had claimed it could. Professor Frederick Alexander Lindemann, 1st Viscount Cherwell (April 5, 1886 - July 3, 1957) was a physicist who became an influential scientific adviser to the British government and a close associate of Winston Churchill. ...

Lindemann's claim was proven untrue when Churchill ordered a flight to try to detect the beams. An Avro Anson was equipped with an American Hallicrafters S-27 amateur radio (then the only known receiver capable of receiving the 40 MHz signal) requisitioned from a shop in Lisle Street, London. The Anson was far from ideal being slow, cold and extremely noisy. It was the only aircraft capable of carrying the radio set and the motor-generator set required to power it that could be spared. The motor-generator was required because the S-27 was a mains powered set but the Anson only had a 28 volt DC electrical system. The flight was nearly cancelled when Eckersly withdrew his claim that the beams would bend round the earth enough to be received. Only R V Jones could save the flight by pointing out that Churchill himself had ordered it and he would make sure that Churchill would get to know who cancelled it. The Avro Anson was a twin-engine, multi-role aircraft that served with the Royal Air Force, Fleet Air Arm and numerous other air forces during World War II and afterwards. ... Ham radio station with modern solid-state transceiver featuring LCD display and DSP capabilities Ham radio station with vintage vacuum tube gear featuring separate transmitter, receiver and power supply Amateur radio, often called Ham radio, is a hobby and public service enjoyed by about 6 million people throughout the world. ... St Jamess is an area of west central London, England. ...

The aircraft was piloted by Flt Lt Boughton (a skilled beam approach pilot). The radio operator was Cpl Mackie of the Y Service the specialist intercept service. The name of the navigator is not known. The crew were told nothing of what they were doing but were ordered to search for radio signals around 40 MHz having Lorenz characteristics and, if they found any, to determine their bearing. The flight took off and eventually flew into the beam from Kleve. It subsequently located the cross beam from Stollberg (its origin was unknown prior to this flight). The radio operator and navigator were able to plot the path of the beams and made the terrifying discovery that they crossed right over the Rolls-Royce engine factory at Derby, at that time the only factory producing the precious Merlin engines for the Hurricane and Spitfire fighters. It was subsequently realised that the argument over whether the beams would bend round the earth or not was entirely academic as the transmitters were, more or less, in the line of sight to a bomber flying at high altitude. Rolls-Royce Limited was a British car and aero-engine manufacturing company founded by Henry Royce and C.S. Rolls in 1906 and was the result of a partnership formed in 1904. ... For other uses, see Derby (disambiguation). ... The Merlin was a 12 cylinder, 60° V, 27 litre, liquid cooled piston aircraft engine built during World War II by Rolls-Royce and under licence in the United States by Packard. ...

Skeptics started regarding the system as proof that the German pilots weren't as good as their own, who could do without such systems. It was Lindemann himself who proved this wrong, when his "photoflash" systems started returning photographs of the RAF bombing raids, showing that they were rarely, if ever, anywhere near their targets.

Efforts to block the Knickebein were brilliant in their simplicity (and aptly codenamed "aspirin"). Initially, modified medical dithermy sets transmitted interference, but later, on nights where raids were expected, local radio transmitters broadcast a surplus "dot signal" at low power. The German predilection for turning on the beams long before the bombers reached the target area aided the British efforts, as it allowed them to determine the target and turn on only those transmitters. Ansons fitted with receivers would be flown around the country in an attempt to capture the beams location, and a successful capture would then be reported to the proper broadcasters.

The low-power "dot signal" was initially broadcast essentially at random, so German navigators would hear two dots. This meant there were many equi-signal areas, and no easy way to distinguish them except by comparing with a known location. The English broadcasters were later modified to broadcast their dots at the same time the German transmitters would, making it impossible to tell which signal was which. In this case the navigators would receive the equi-signal over a wide area, and navigation along the bombline became impossible, with the aircraft drifting into the "dash area" and no way to correct for it.

Thus the beam was "bent" away from the target. Eventually, the beams could be bent by a controlled amount which enabled the British to fool the Germans into dropping their bombs where they wanted them. A side effect was that as the German crews had been trained to navigate solely by the beams, many crews failed to find either the true equi-signal or Germany again. Some bombers even landed at RAF bases, believing they were back in Germany.

X-Gerät

Main article: X-Gerät (navigation)

As good as Knickebein was, it was never invented to be used in the long-range role. Efforts had been underway for some time to produce a much more accurate version of the same basic concept, which was eventually delivered as X-Gerät (Secret (i.e. unknown) Apparatus). X-Gerät (X-gadget) was a radio navigation system used by the Luftwaffe early in World War II to aid bomber navigation. ... X-Gerät (X-gadget) was a radio navigation system used by the Luftwaffe early in World War II to aid bomber navigation. ...

X-Gerät used a series of beams to locate the target, each beam named for a river. The main beam, Weser, was similar in concept to the one used in Knickebein, but operated at a much higher frequency. Due to the nature of radio propagation, this allowed its two beams to be pointed much more accurately than Knickebein from a similarly sized antenna; the equi-signal area was only about 100 yards wide at a distance of 200 miles from the antenna. The beams were so narrow that bombers couldn't find them on their own, so a low-power wide-beam version of Knickebein was set up at the same station to act as a guide. The main Weser broadcast antenna was set up just to the west of Cherbourg. Cherbourg-Octeville is a town and commune in Normandy, north-west France. ...

The "cross" signal in X-Gerät used a series of three very narrow single beams, Rhine, Oder and Elbe. About 30 km from the target the radio operator would hear a brief signal from Rhine, and set up his equipment. This consisted a special stopclock with two hands. When the Oder signal was received the clock automatically started and the two hands started to sweep up from zero. When the signal from Elbe was received clock reversed, at which point one hand would stop and the other would start moving back towards zero. Oder and Elbe were aimed to be roughly 10 and 5 km from the bomb release point along the line of Weser (the exact distance depending on the distance from the transmitter), meaning that the clock accurately measured the time to travel between the first two beams (whatever it was). Since the time taken to travel that distance should be the same as the time needed to travel the last 5km from Elbe to the target, when the moving hand reached zero the bombs were automatically released. To be exact, the Elbe signal was adjusted to correct for the distance the bombs would travel between release and impact.

Since X-Gerät operated on a much higher frequency than Knickebein (around 60 MHz) it required new radio equipment to be used. There were not nearly enough sets to go around, so instead the experimental unit KGr 100 was given the task of using their sets in order to guide other planes to the target. To do this, KGr 100 planes would attack as a small group first, dropping flares which other planes would then see and bomb visually. This is the first use of the pathfinder concept that the RAF would later perfect to great effect against the Germans only a few years later. The Pathfinder squadrons of the Royal Air Force were elite squadrons of RAF Bomber Command during World War II. During World War II the RAF Bomber Command practiced mainly night bombing. ...

X-Gerät was used to great effect in a series of raids known to the Germans as Moonlight Sonata, against Coventry, Wolverhampton and Birmingham. In the raid on Birmingham only KGr 100 was used, and British post-raid analysis showed that the vast majority of the bombs dropped were placed within less than 100 yards of the midline of the Weser beam, spread along it a few hundred yards. This was the sort of accuracy that day bombing could rarely achieve. A similar raid on Coventry with full support from other units dropping on their flares nearly destroyed the city center. The city from above Centenary Square. ... The Precinct in Coventry city centre. ...

Stopping X-Gerät proved to be more difficult than with Knickebein. Intital defences against the system were deployed in a similar fashion to Knickebein in an attempt to disrupt the Coventry raid, but proved to be a total failure. Although R V Jones had correctly guessed the beam layout (and he acknowledges that that is all they were), the modulation frequency had been actually been measured, but measured incorrectly. It was measured at 1500 Hz, but was in fact 2000 Hz. At the time it was believed that this would not make any difference, as the tones were close enough that an operator would have a hard time distinguishing them in an noisy aircraft.

The mystery was eventually revealed after an X-Gerät equipped Heinkel He 111 crashed on the English coast at Chesil Beach. Although it crashed just prior to the Coventry raid, an inter-service dispute prevented recovery of the X-Gerät equipment until after the incoming tide had covered and damaged it. On later examination it was learned that a new instrument was being used that automatically decoded the dots and dashes and displayed a pointer in the cockpit in front of the pilot. This device was fitted with a very sharp filter which was sensitive only at 2000 Hz, and not the early British 1500 Hz counter-signals. He 111K The Heinkel He 111 was the primary Luftwaffe medium bomber during the early stages of World War II, and is perhaps the most famous symbol of the German side of the Battle of Britain. ... Chesil Beach from Fortuneswell Looking west down Chesil Beach by Abbotsbury Satelite view of Chesil Beach (shown blue) and Portland Bill (Landsat image viewed using NASA World Wind software) Portland and Chesil Beach from Abbotsbury Castle A fossil from the far western end of Chesil Beach Chesil Beach (sometimes called...

X-Gerät was eventually defeated in another manner, by way of a "false Elbe" which was set up to cross the Weser guide beam not at 5km, but at 1km. Since the final stages of the release were automatic, the clock would reverse prematurely and drop the bombs kilometers short of the target. Setting up this false beam proved very problematic as the Germans, learning from their mistakes with Knickebein, didn't switch the X-Gerät beams on until as late as possible, making it much more difficult to arrange the "false Elbe" in time.

Y-Gerät

As the British slowly gained the upper hand in the Battle of the Beams, they started considering what the next German system would entail. Since Germany's current approaches had been rendered useless, an entirely new system would have to be developed. It was thought that if England could defeat this new system very quickly, the Germans would abandon their attempts entirely.

England soon started receiving intelligence intercepts referring to a new device known as Y-Gerät, which was also sometimes referred to as Wotan. R V Jones had long since realised that the Germans used code names that were far too literal. Asking around, he learned that Wotan was the name of a one-eyed god. He deduced that Y-Gerät used a single beam. From this, they concluded that Wotan would have to be based on a distance-measurement system. He also concluded that it might well work on the system that was described by a German well-wisher in Norway, who had passed a large amount of information in what is now known as the Oslo Report. The information was plentiful and apparently far too useful to be true, and many considered it to be a German disinformation campaign. The Oslo Report's description of Wotan was entirely accurate, however, and the Report was later realised to be "for real". Professor R V Jones Reginald Victor Jones (29 September 1911 – 17 December 1997) was an English physicist and scientific military intelligence expert who played an invaluable role in the defence of Britain in World War II. // Biography Born in Dulwich, Jones was educated at Alleyns School, Dulwich and Wadham... This is the article about the West Germanic deity, for other uses see Woden (disambiguation), Wotan (disambiguation). ... The Oslo Report was an anonymous report found and recovered by the British on a windowsill of their Oslo embassy on November 4, 1939. ...

Y-Gerät used a single narrow beam pointed over the target, broadcasting a modulated radio signal. The system used a new piece of equipment that received the signal from the beam and immediately re-broadcast it back to the ground station. The ground station listened for the return signal and compared its phase to the transmitted signal. This is an accurate way of measuring the transit time of the signal, and hence the distance to the aircraft. Coupled with the direction of the beam (adjusted for maximum return signal), the bomber's position could be established with considerable accuracy. The bombers did not have to track the beam, instead the ground controllers could calculate it and then gave radio instructions to the pilot to correct the flight path. A major disadvantage of the system was that it only allowed one aircraft to be tracked at a time.

The British were ready for this system even before it was used. The Germans had chosen the operating frequency of the Wotan system very badly; it operated on 45 MHz, which just happened to be the frequency of the powerful but dormant BBC television transmitter at Alexandra Palace. All Jones had to do was arrange for the return signal to be received from the aircraft and sent it to Alexandra Palace for re-transmission. The combination of the two signals modified the phase shift — and the apparent transit delay. Initially the signal was re-transmitted at a low power, not powerful enough for the Germans to realise what was happening, but enough to spoil the accuracy of the system. Over subsequent nights the transmitter power was gradually increased. The British Broadcasting Corporation, usually known as the BBC (and also informally known as the Beeb or Auntie) is the largest broadcasting corporation in the world in terms of audience numbers, employing 26,000 staff in the United Kingdom alone and with a budget of more than GB£4 billion... The transmission mast above the BBC wing of Alexandra Palace, photographed in 2001. ...

As Wotan's use went on, the aircrew accused the ground station of sending bad signals and the ground station accused the aircraft of having loose connections. The whole scheme appealed to Jones as he was a natural practical joker, and remarked that he was able to play one of the largest practical jokes with virtually any national resource that he required. The gradually increasing power conditioned the Germans such they did not realise that anyone was interfering with the system, but believed that it suffered several inherent defects. Eventually, as the power was increased enough, the whole Wotan system started to ring with all the feedback.

The Germans eventually realised what was happening and the Luftwaffe's faith in electronic navigation aids was completely shattered. The bombing offensive of Britain waned, partly because of the abandonment of electronic aids, but mainly because Hitler's attention was turning to Russia.

See also

• List of World War II electronic warfare equipment
• Kammhuber Line
• Chain Home

List of World War II electronic warfare equipment and code words Airborne Cigar (A.B.C.) - Jamming transmitter carried by 101 Sqn Lancasters using 8th crew member to monitor and then jam German nightfighter frequencies Berlin - German night fighter radar, introduced April 1945, centrimetic radar (9cm) Boozer - Fighter radar early... The Kammhuber Line was the name given to the German night air defense system established in July 1940 by Colonel Josef Kammhuber. ... Chain Home was the codename for the ring of coastal radar stations built by the British during World War II. The system comprised two types of radar: the metre-wave Chain Home stations which provided long-range early warning, and the centimetre-wave Chain Home Low stations, which were shorter...

Combatants Allied powers: China France Great Britain Soviet Union United States and others Axis powers: Germany Italy Japan and others Commanders Chiang Kai-shek Charles de Gaulle Winston Churchill Joseph Stalin Franklin Roosevelt Adolf Hitler Benito Mussolini Hideki Tōjō Casualties Military dead: 17,000,000 Civilian dead: 33,000... The Royal Air Force (RAF) is the air force branch of the British Armed Forces. ... The Royal Canadian Air Force (RCAF) was the air force of Canada from 1924 until 1968 when the three branches of the Canadian military were merged into the Canadian Forces. ... The remains of German town of Wesel after intensive Allied area bombing in 1945 (destruction rate 98 % of all buildings) // Strategic bombing is a military strategy used in a total war style campaign that attempts to destroy the economic ability of a nation-state to wage war. ... A night fighter is a fighter aircraft adapted for use at night, or in other times of bad visibility. ... “Dowding” redirects here. ... RAF Air Chief Marshal Charles Portal (left) and Polish Commander in Chief Władysław Sikorski (right) visit an airbase of the 300th Polish Bomber Squadron in England. ... Marshal of the Royal Air Force Cyril Louis Norton Newall, 1st Baron Newall GCB OM GCMG CBE AM (February 15, 1886 – November 30, 1963), was a British pilot and political figure who rose to the Royal Air Forces senior rank and served as Governor-General of New Zealand between... Air Chief Marshal Sir Trafford Leigh-Mallory KCB, DSO and Bar (11 July 1892 - 14 November 1944) was a senior commander in the Royal Air Force in World War II and the highest-ranking British officer to die in the war. ... Air Chief Marshal Sir Keith Rodney Park GCB, KBE, MC, DFC, DCL (June 15, 1892 - February 6, 1975) was a senior commander in the Royal Air Force in World War II. // Early Life and Army Career Park was born near Auckland, New Zealand. ... Professor R V Jones Reginald Victor Jones (29 September 1911 – 17 December 1997) was an English physicist and scientific military intelligence expert who played an invaluable role in the defence of Britain in World War II. // Biography Born in Dulwich, Jones was educated at Alleyns School, Dulwich and Wadham... No. ... No. ... Fighter Command was one of three functional commands that dominated the public perception of the RAF for much of the mid-20th century. ... Balloon Command was the Royal Air Force command which was responsible for controlling all the United Kingdom-based barrage balloon units during World War II. Balloon Command was formed on 1 November 1938 at Stanmore in Middlesex. ... The U.S. Womens Auxiliary Air Force was created in June of 1939. ... The Royal Observer Corps (ROC) was, until stood down in 1991, a part of the UK Ministry of Defence. ... The Eagle Squadrons were Royal Air Force fighter squadrons formed during World War II from American volunteer pilots. ... Combatants United Kingdom Including combatants from:[1] Poland New Zealand Canada Czechoslovakia Belgium Australia South Africa France Ireland United States Jamaica Palestine Rhodesia Germany Including combatants from Italy Commanders Hugh Dowding Hermann Göring Albert Kesselring Strength 754 single-seat fighters 149 two-seat fighters 560 bombers 500 coastal 1... Heinkel He 111 German bomber over the Surrey Docks, Southwark, London (German propaganda photomontage). ... The Baedeker Blitz or Baedeker raids were a series of reprisal raids for the bombing of the erstwhile Hanseatic League city of Lübeck during World War II, which was being used to supply the Russian front. ... Similar to Operation Pointblank against the WWII German aircraft industry, Operation Crossbow specialized in offensive and defensive countermeasures against the Bodyline[1] and Peenemünde 20,[2] the British code names for the 40 ft x 7 ft object with blunt nose and three fins and the small winged aircraft... The Hawker Hurricane is a fighter design from the 1930s which was used extensively by the Royal Air Force during the Battle of Britain. ... The Supermarine Spitfire was an iconic British single-seat fighter used primarily by the RAF and many Allied countries through the Second World War and into the 1950s. ... The Bolton-Paul Defiant was a single-engined two-seater fighter-bomber used by the RAF in the late 1930s - early 1940s. ... The de Havilland Mosquito (The Wooden Wonder, also known as The Timber Terror) was a British combat aircraft that excelled in a number of roles during the Second World War. ... The Bristol Beaufighter is also the name of a car produced by Bristol Cars in the 1980s. ... Hawker Tempest II, RAF Museum, Hendon The Hawker Tempest was a Royal Air Force (RAF) fighter aircraft of World War II, an improved derivative of the Hawker Typhoon, and one of the most powerful fighters used in the war. ... The Gloster Meteor was the Allies first operational jet fighter. ... Chain Home was the codename for the ring of coastal radar stations built by the British during World War II. The system comprised two types of radar: the metre-wave Chain Home stations which provided long-range early warning, and the centimetre-wave Chain Home Low stations, which were shorter... US Marine Corps barrage balloon, Parris Island, May 1942 A barrage balloon is a large balloon used as a defense against aircraft. ... Vergeltungswaffe (German for retaliation weapon, reprisal weapon or vengeance weapon) was a term assigned during World War II by the Nazis to a number of revolutionary superweapons, the V1 flying bomb, the V2 rocket and the V3 long range gun. ... The Big Wing, also known as a Balbo, was a air fighting tactic proposed during the Battle of Britain by Acting Squadron Leader Douglas Bader and 12 Group commander Air Vice-Marshal Trafford Leigh-Mallory. ... The United States Army Air Forces (USAAF) was a part of the U.S. Army during World War II. The direct precursor to the U.S. Air Force, the USAAF formally existed between 1941 and 1947. ... The German Luftwaffe was one of the most powerful, doctrinally advanced, and battle-experienced air forces in the world when World War II started in Europe in September 1939. ...   (also Goering in English) (January 12, 1893 – October 15, 1946) was a German politician and military leader, a leading member of the Nazi Party, second in command of the Third Reich, and commander of the Luftwaffe. ...

References

• Jones, R. V. (1978). Most Secret War: British Scientific Intelligence 1939–1945. First published 1978 Hamish Hamilton. Coronet paperback edition 1979 ISBN 0-340-24169-1.