Fieseler Fi 103

V1
V1 flying bomb First modern cruise missile
Description
Role	Flying bomb
Crew	none
Dimensions
Length	7.90 m	25' 11"
Wingspan	5.37 m	17' 7"
Height	1.42 m	4' 8"
Wing area
Weights
Empty
Loaded	2,150 kg	4,750 lb
Powerplant
Engine	1x Argus As 14 pulsejet
Power	2.9 kN	660 lb
Performance
Maximum speed	656 km/h	410 mph
Range	240 km	150 mile
Service ceiling	3,050 m	10,000 ft
Rate of Climb
Armament
Amatol warhead	830 kg	1,832 lb

The Vergeltungswaffe 1 FZG-76 (V1), known as the Flying Bomb, Buzz Bomb or Doodlebug, was the first modern guided missile used in wartime and the first cruise missile. Vergeltungswaffe means "reprisal weapon", and FZG is an abbreviation of Flak Ziel Gerät ("anti-aircraft aiming device"), a misleading name.

Called the Buzz Bomb because of the characteristic buzzing sound of the engine, it caused considerable fear in targeted areas. People would listen for the missile approaching, but then be relieved when it could be heard overhead as that meant it had actually passed them. If the engine noise cut out, it was time to duck, as the missile would then go into its terminal dive.

The V1 was developed in Germany during the Second World War and was used operationally between June 1944 and March 1945. It was used to attack targets in south-eastern England and Belgium, mainly the cities of London and Antwerp. V1s were launched from "ski-jump" launch sites along the French (Pas-de-Calais) and Dutch coasts until they were over-run by Allied forces. It was later complemented by the more sophisticated V2 rocket.

 

Description

The V1 was jointly designed by Robert Lusser of the Fieseler company and Fritz Gosslau from the Argus engine works as the Fi 103. It was powered by an Argus pulse jet engine providing 2.9 kN (660 pounds) of thrust for a top speed of 630 km/h (390 mph) and a range of around 250 km (150 mile) later 400 km (250 mile). It was 7.9 m (26 ft) long, 5.3 m (17 ft) in span and weighed 2,180 kg (4,800 pound). It flew at an altitude of between 100 to 1000 m (300 to 3000 ft). It carried a 850 kg (1,870 pound) warhead. The missile was a relatively simple device with a fuselage constructed mainly from sheet metal, and could be assembled in around fifty man-hours.

The guidance system was very crude in construction but sophisticated in conception (and had a few flaws in execution). Once clear of the launching pad, an autopilot was engaged. It regulated height and speed together, using a weighted pendulum system to get fore and aft feedback linking these and the device's attitude to control its pitch (damped by a gyro magnetic compass, which it also stabilized). There was a more sophisticated interaction between yaw, roll, and other sensors: a gyro magnetic compass (set by swinging in a hangar before launch) gave feedback to control each of pitch and roll, but it was angled away from the horizontal so that controlling these degrees of freedom interacted (the gyroscope stayed trued up by feedback from the magnetic field, and from the fore and aft pendulum mentioned before). This interaction meant that rudder control was sufficient without any separate banking mechanism. On reaching the target, the desired altitude was reset to be negative; this should have led to a power dive, but the steep descent caused the fuel to run away from the pipes and so the power cut out. As there was a belly fuse as well as a nose fuse, there was still usually an explosion, although not always with the device buried deep enough to increase the effect of the blast.

 

Operation and impact

The first test flight of a V1 was in late 1941 or early 1942 at Peenemünde. Early guidance and stabilization problems were finally resolved by a daring test flight by Hanna Reitsch, in a V1 modified for manned operation. The data she brought back after fighting the unwieldy V1 down to a successful landing enabled the engineers to devise the stabilization system described above.

The first offensive launch was on June 12, 1944. The Allies organized a heavy series of air attacks on the launch sites and also attacked the V1s in flight (see Countermeasures below). Due to a combination of defensive measures, mechanical unreliability and guidance errors, only a quarter successfully hit their targets.

Once the Allies had captured or destroyed the sites that were the principal launch points V1s aimed at England, the Germans switched to missile launches aimed at strategic points in the Low Countries, primarily the port of Antwerp.

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Arado Ar 234

Although most V1s were launched from static sites on land, from July 1944 to January 1945 the Luftwaffe launched a number of V1s from Heinkel He 111 aircraft flying over the North Sea. This would also have been the launch method for the proposed piloted version of the weapon. Late in the war, it was hoped to use the Arado Ar 234 jet bomber to deploy V1s, either by towing them aloft, or by launching them from a "piggy back" position atop the aircraft. Neither Ar 234 concept was employed before the end of the war.

Almost 30,000 V1s were manufactured. Approximately 10,000 were fired at England up to March 29, 1945. Of these, about 7,000 were "hits" in the sense that they landed somewhere in England. A little more than half of those (3,876) landed in the Greater London area.

An almost equal number were shot down or intercepted by barrage balloons. When the V1 raids began, the only effective defense was interception by a handful of very high performance fighter aircraft, in particular the Hawker Tempest.

In the London area, roughly 5,500 people died as a result of V1 attacks, with some 16,000 more people injured.

 

Countermeasures

Anti-aircraft gunners found that such small, fast-moving targets were difficult to hit. At first, it took, on average, 2500 shells to bring down a single V1. Most fighter aircraft were too slow to catch a V1 unless they had a useful height advantage. Even when caught, the V1 was difficult to bring down. Machine gun bullets had little effect on the sheet steel structure, and 20mm cannon shells had a shorter range, which meant that detonating the warhead could easily destroy the intercepting fighter as well. Barrage balloons were a theoretical obstacle, but the leading edges of the V1's wings were equipped with balloon cable cutters and fewer than 300 V1s are known to have been destroyed by hitting cable.

When the attacks began in mid-June of 1944 there were fewer than 30 Tempests in 150 Wing to defend against them. Few other aircraft had the low altitude performance to be effective. Initial attempts to intercept V1s were often unsuccessful but interdiction techniques were rapidly developed. (These included the hair-raising but effective method of using the airflow over an interceptor's wing to raise one wing of the Doodlebug, by sliding the interceptor's wingtip under the V1's wing and bringing it to within six inches of the lower surface. Done properly, the airflow would tip the V1's wing up, overriding the buzz bomb's gyros and sending it into an out of control dive. At least three V1s were destroyed this way.)

The Tempest wing was built up to over 100 aircraft by September; Griffin-engined Spitfire XIVs and Mustangs were polished and tuned to make them almost fast enough, and during the short summer nights the Tempests shared defensive duty with Mosquitoes. Specially modified P-47 Thunderbolts (P-47Ms) with half their fuel tanks, half their 0.5 in (12.7 mm) machine guns, all external fittings and all their armor plate removed were also pressed into service against the V1 menace. (There was no need for radar - at night the V1's engine could be seen from 16 km (10 mile) or more away.)

In daylight, V1 chases were chaotic and often unsuccessful until a special defence zone between London and the coast was declared in which only the fastest fighters were permitted. Between June and mid-August 1944, the handful of Tempests shot down 638 flying bombs. (One Tempest pilot, Joseph Berry, downed fifty-nine V1s, another 44, and Wing Commander Beaumont destroyed 31.) Next most successful was the Mosquito (428), Spitfire XIV (303), and Mustang, (232). All other types combined added 158. The still-experimental jet-powered Gloster Meteor, which was rushed half-ready into service to fight the V1s, had ample speed but suffered from a readily jammed cannon and accounted for only 13.

By mid-August 1944, the threat was all but overcome - not by aircraft, but by the sudden arrival of two enormously effective electronic aids for anti-aircraft guns, both developed in the USA by the Rad lab: radar-based automatic gun laying, and above all, the proxciminitry fuse. Within weeks, the vast majority of V1s launched were shot down by anti-aircraft guns as they crossed the coast. The kill rate increased from one V1 for every 2500 shells fired to one for every hundred.

Officially, it was simply FZG-76-Flakzielgerät (anti-aircraft target device)-76. The anti-aircraft designation was a ruse to throw Allied spies off the track. In Britain, it was known as the "doodlebug" "buzz bomb" and "farting fury," along with a number of other comic names.   The Fieseler company that designed it designated it the Fi-103. The Nazi Propaganda Ministry called the pilot-less aircraft Vergeltungswaffe (retaliation weapon) 1, or V-1. But the name almost universally favored by Britons and Americans alike was "buzz bomb."   A V-1 flying bomb resembled a small aircraft with a stovepipe mounted over its tail and no cockpit. Its overall length was just over 25 feet, with a wingspan of 17 feet. Standard 80-octane gasoline kept its jet engine running, which was housed in the stovepipe assembly; this was the same fuel used by trucks. The flying bomb was easy and cheap ($500) to build and carried a 1,870-pound warhead. But while the flying bomb may have been cheap and simple, it was not very accurate-it could not hit small targets, or even moderate-sized villages. It was accurate enough to hit a target the size of Greater London, however, and that was all that was expected - a way to hit back at the Allies without risking the depleted reserves of the Luftwaffe's bomber fleet.   During the early months of 1943, extensive tests were carried out involving the FZG-76. Only nine months had passed between the beginning of work on the project in March 1942 and the first successful launch, which took place on Christmas Eve, although the flying bomb still had its share of teething problems. One question involved the proper type of launching site for the flying bombs. Some favored large concrete emplacements; others proposed small, portable sites. As head of the Luftwaffe, Reichsmarschall Hermann Göring compromised, ordering four concrete bunkers and 96 smaller sites begun immediately.   Next, men had to be trained to handle and fire the flying bomb. A new Luftwaffe unit was formed in August 1943, called Flakregiment 155 ('N). The anti-aircraft designation was, once again, aimed at deceiving Allied intelligence.   The new unit was placed under the command of Luftwaffe Colonel Max Wachtel, who had been in charge of all the experimental flying bomb launches. Wachtel was instructed to get his men ready for firing the bomb under actual combat conditions, and he took his orders to heart; his Flakregiment began exercises within days of the unit's creation. From the western side of Peenemünde, on Usedom Island in the Baltic Sea, the launching crews began readying the small, jet-propelled planes and firing them downrange over the Baltic.   Under Wachtel, Flakregiment 155 ('N) continued its training through the winter of 1943 and into 1944. ByJune 1944, Wachtel and his unit were in France, ready to begin operations. But few others connected with the flying bomb project were as efficient as Wachtel.   One of the main problems was with the production of the flying bombs themselves. Because of the many defects that plagued the bomb, it did not go into production until March 1944. Engineers at the Volkswagen plant at Fallersleben, near Hamburg, did their best to work out the problems, but the pilotless planes kept crashing immediately after launching. Full production did not begin until April 1944, when 1,000 flying bombs rolled off the Volkswagen assembly line.   Wachtel had been ordered to begin launching the pilotless bombs against England by June, but his unit had no equipment, no launching rails and no supplies. It had been decided that lightweight launching ramps, called modified sites, would be used in place of larger ramps that had proved too vulnerable to Allied bombing attacks.   The supplies and equipment that Wachtel needed to begin operations did not arrive until June 12, 1944, only a few hours before he was to begin launching V-is against southern England. Only 10 ramps were ready for launching; 55 were supposed to have been prepared, but not enough spare parts and equipment had been sent for all of them. By 3:30 am, on June 13, the 10 firing ramps were ready. The Luftwaffe high command decided to go ahead despite the fact that so few ramps were operational.   Months of practice made the pre-launch procedure a set routine for the crews. First, the flying bomb's fuel tank was checked, to make certain that it had been topped off. Following this, the wooden wings were attached-these had been folded over the fuselage to make storing and moving the aircraft easier. After assembly, the plane was aligned precisely with its firing ramp-which was pointed directly at London - and its gyrocompass was set at zero to ensure it flew the straight course on which it had been aimed.   The flying bomb, now ready for launching, was moved onto its firing ramp. After it was loaded onto its catapult, a lug on the underside of the fuselage was attached to the catapult's firing piston. When the piston was released, it accelerated the V-1 off the launch rails in the same way that a jet plane is catapulted off the flight deck of an aircraft carrier. With the stubby-winged flying bomb poised for takeoff, the launching crew took cover inside the "control bunker," a heavily armored trailer that housed the catapult's firing controls, or lumped into a nearby slit trench. The firing officer gave an order, a technician pulled a lever, and the flying bomb's pulse-jet engine came to life with a throbbing, ear-numbing roar.   This simple jet engine was the flying bomb's most unique feature. Housed outside the fuselage, above the tail, the jet is usually described as looking like either a stovepipe or a giant blow torch. At the front end of the engine housing was a set of intake flaps that resembled a Venetian blind. These flaps opened at the beginning of the engine's cycle, allowing air to be drawn into the combustion chamber, where it was mixed with 80-octane fuel. In the second stage of the combustion cycle, the flaps closed and the fuel-oxygen mixture was ignited. With a tremendous flash, a burst of hot exhaust shot out from the rear of the engine to provide forward thrust. Immediately following the exhaust stage, the intake flaps opened again, allowing air into the combustion chamber and repeating the cycle.   This simple jet engine could complete up to 500 combustion cycles every minute, giving the flying bomb a maximum speed of about 400 mph. The engine's pulsing combustion process also gave the flying bomb its distinctive duv-duv-duv sound in flight, a sound that Londoners would soon come to recognize.   After listening for a moment to ensure that the engine was firing properly, the firing officer gave the order to launch. A second lever was pulled, releasing the catapult's piston. The flying bomb lurched forward, shot along the length of steel rail, and lumped uncertainly into the night sky. During the next half-hour, between ab out 3:30 and 4 a.m., nine more of the bombs bolted from their catapults. The launching crews watched as the small aircraft left their ramps, brilliant flashes of fire trailing from their exhausts.   Four of the shots failed, the flying bombs crashing just after takeoff, with explosions loud enough to hurt the eardrums of the catapult crews. Two of the successfully launched flying bombs crashed into the English Channel. The other four reached England; two landed in Kent, one in Surry, and one crashed in London, the intended target of all of them. The London bomb came down in Bethnal Green, East London, about three miles away from its Tower Bridge target point. The explosion killed three people and knocked out a railway bridge.   Although only four flying bombs reached England during this first launch, hundreds more would be launched during the next several weeks. An inexpensive, and not very accurate, mechanism sent the flying bomb diving into its target upon arrival. Each bomb had a small, propeller like anemometer device on its nose that was connected to the bomb's autopilot. As the flying bomb flew through the air, its forward motion turned the propeller like a pinwheel in the wind. After a preset number of revolutions, the propeller tripped the diving controls, pointing the bomb earthward at a steep angle. The mechanism was set by the catapult crew before launching; the setting of how many revolutions were needed to trip the diving controls was based upon calculations involving the flying bomb's speed and the distance to target.   Any number of factors could undo this inherently imprecise system. Headwinds or tailwinds could alter the machine's groundspeed, mining carefully worked-out calculations that were usually a lot more accurate than the mechanism itself. The autopilot might go haywire and send the bomb plunging into the Channel. Or it might not work at all, causing the bomb to overfly London and keep going until it ran out of fuel. When the windmill device tilted the bomb toward the earth, all the fuel ran to one end of the tank - the end away from the fuel pump. The pump began drawing air, and the engine, cut off from its fuel supply, stopped running.

The Germans performed experiments with autopiloted aircraft in the 1930s, but proposals made to the German military in 1939 and 1941 to develop flying bombs were turned down. In June 1942, however, growing RAF bomb raids on German cities, and rising losses of Luftwaffe bombers over England in attempts to retaliate, persuaded the Luftwaffe to consider new options. Work on the V-2 long-range rocket was encountering difficulties, and the V-2 was an Army project in any case.

The Luftwaffe investigated and approved the development of a small, cheap flying bomb, with a range of about 250 kilometers (155 miles) and an 800 kilogram (1,760 pound) warhead, that could hit a city-sized area, evading interception by flying in at high speed and low altitude. The project was given the cover designation of "Flak Ziel Gerät (FZG)", or "anti-aircraft target apparatus".

Propulsion for the new flying bomb was provided by the "pulsejet", which had been invented by Paul Schmidt in the early 1930s, with development picked up by the Army Weapons Office in 1937. The pulsejet was little more than a "stovepipe", with its sole moving part consisting of a shutter assembly inside the air intake. The simplicity and low cost of this engine was a major factor in the Luftwaffe's decision to pursue flying bomb development.

Air entering into the pulsejet was mixed with fuel and the mixture ignited by spark plugs. The combustion of the mixture slammed the intake shutters closed, and produced a burst of thrust out the exhaust. The shutters then opened again in the airflow. The production engine would perform this cycle about 42 times a second. This pulsed operation caused the engine to emit a loud low throbbing sound that would presently become familiar over the English countryside.

Schmidt's pulsejet was a crude engine. Throttling it was difficult at best, it could only operate effectively at low altitudes, and the shutters tended to wear out quickly, but none of these issues were important in an expendable robot weapon, and it had major advantages. It was simple, cheap, and powerful, with a thrust of 270 kilograms (600 pounds). Furthermore, it could use low-grade gasoline as a fuel, rather than precious high-octane aviation fuel.

Three companies collaborated in building the flying bomb. Fieseler built the airframe; Argus, the employer of Paul Schmidt, built the pulsejet engine; and Askania built the guidance system. A glide test of the flying bomb was performed from a Focke-Wulf FW-200 Kondor in early December 1942, followed by a powered flight on Christmas Eve.

The first powered flight only went a kilometer, and the early prototypes showed a distressing tendency to crash. To resolve these problems, a piloted flying bomb was developed, with the warhead replaced by a cockpit in which a test pilot could fly the machine while lying prone. Test flights were performed with the tiny and daring female test pilot Hanna Reitsch at the controls, and helped resolve the problems.

On 26 May 1943, top Nazi officials visited the test facility at Peenemünde, on the Baltic, to evaluate progress on the flying bomb. They concluded that the weapon should be put into full-scale production, and work was accelerated on completing development; establishing an operational unit to fire the weapons; and constructing launch sites. A hundred launch sites were to be built in the Pas de Calais area in northwest France, capable of launching a thousand flying bombs a day. London was only about 200 kilometers (120 miles) from the launch sites.

The flying bomb was refined into a production prototype version, codenamed "Kirschkern (Cherrystone)", that was much superior to the initial prototypes. In production, the weapon was officially designated the "Fieseler Fi-103" or "FZG-76", but was more informally referred to as the "V-1", for "Vergeltungswaffe Eins", or "Vengeance Weapon 1".

RAF photo-reconnaissance aircraft had been observing the strange goings-on at Peenemünde since the middle of May 1942, and though Allied intelligence wasn't sure about what was going on, it was clearly nothing good. The RAF launched Operation Hydra, a major bomb raid on Peenemünde, in the late summer of 1943, though it did not greatly slow down German development efforts. Shortly thereafter, the USAAF bombed the launching sites in the Pas de Calais, destroying most of them.

On 28 November 1943, an RAF photo-reconnaissance aircraft took pictures of Peenemünde, and a sharp-eyed photographic analyst, Flight Officer Babington Smith, spotted a prototype flying bomb on a launch ramp at Peenemünde. British intelligence began to see what the Germans were up to, and estimated that the Germans would be able to start launching these new weapons against England in a matter of weeks.

Bombings of new launch sites under construction were stepped up. However, by this time the flying bomb was in production, and the new launch sites were more easily concealed. Several flying bombs were launched towards Sweden in last-minute tests to determine their range and other performance characteristics, and on 13 June 1944, the first V-1s were launched towards London.

Only about ten missiles were fired that day. The commandant in charge of the launch sites had been ordered to launch, but he was not quite ready to begin full scale launch operations at that time. He simply did as he was ordered, then returned to finishing his preparations.

The "Flying Bomb Blitz" began in earnest on 15 June 1944, with 244 fired at London and 50 fired at Southampton. 144 crossed the English coast; 73 managed to reach London; some were shot down; most of the rest landed south of the Thames; and a few hit Southampton. One went wildly astray and ended up in Norfolk.

 

 V-1 Details

The V-1 was an odd and ingenious weapon, designed to be cheaply built in large numbers. Early production was largely made of metal, though wooden wings were quickly introduced. The V-1 was directed to its target by a simple guidance system, which incorporated a set of gyroscopes driven by compressed air to keep the missile stable; a magnetic compass to control bearing; and barometric altimeter to control altitude.

The flying bomb was typically set to fly at an altitude of about 600 meters (2,000 feet) under the control of the barometric altimeter. A spinner on the nose armed the warhead after about 100 kilometers (60 miles) of flight, and determined when the weapon would fall to earth. Some sources claim that this function was performed by a simple clock, not a nose spinner. Illustrations are ambiguous on this issue, and it is possible that different production runs used different systems.

The little aircraft's wings had no control surfaces. The V-1 was directed by the rudder and elevators on its horizontal tailplane. As there was no way the flying bomb could maneuver anyway, such a crude approach was both adequate and cheap.

When the guidance system determined that the missile was over its target, it locked the control surfaces, and popped out spoilers under the horizontal tailplane to put the bomb into a steep dive. Usually, though not always, this stalled the engine. The abrupt cutoff of the loud buzz inspired terror, since it meant there would be a terrific explosion a few seconds later.

The V-1's warhead included a electrical fuze; a backup mechanical fuze; and a time-delay fuze, to ensure that the weapon destroyed itself if the other fuzes failed to work. The fuzing system was very reliable, and very few V-1s were duds.

Early V-1 production had a fuel capacity of 640 liters (169 US gallons). Flight time from launch to impact was usually about 22 minutes. Accuracy was very poor, with impacts scattered all over southeastern England.

The V-1 was prepared for launch by filling up its fuel tank, installing a battery, and charging up the compressed air tanks for the gyroscopes. It was then trollied to a demagnetized area to check the missile's magnetic compass and set up the guidance system in accordance with the planned target coordinates.

Click on Picture to enlarge

 As the Argus pulsejet engine couldn't produce effective thrust until the flying bomb was up to flight speed, the V-1 was launched off a 48 meter (157 foot) long ramp using a steam catapult system, designed by the Walter company. The ramp contained a slot fitted with a dumbbell-shaped piston, and the flying bomb sat on a simple trolley that was linked to the piston. The piston was held in place with a shear pin.

A cart containing a reaction chamber and tanks of with hydrogen peroxide (HO) and granules of potassium permanganate (KMnO4) catalyst was connected to a chamber at the base of the ramp whose other end was plugged by the piston. When the hydrogen peroxide was pumped over the potassium permanganate, it was converted into large quantities of hot steam that built up pressure against the piston. When the pressure built up to a certain level, it broke the piston's shear pin and the trolley rapidly moved up the ramp.

The V-1 left the ramp at a speed of about 400 kph (250 mph), while the piston shot out into the surrounding terrain and the trolley fell off the weapon. After a firing, the launch ramp had to be swept off by personnel clad in protective clothing, as the fuel spatterings were corrosive.

The V-1 could be fitted with a poison gas warhead, which would have made it a truly fearsome weapon, considering the highly lethal nerve gases that the Germans possessed. However, fear of retribution in kind kept Hitler from performing poison gas attacks, as German gas warfare experts wrongly believed that the Allies had nerve gases as well.

Some of the V-1s were fitted with a radio transmitter and a trailing antenna wire so that their flight could be monitored. In some cases, the bombs were "shadowed" by fast aircraft like the Messerschmitt 410 to observe their flight. A few were also fitted with a cage to accommodate 23 one-kilogram incendiary bombs, or a paper carton full of propaganda leaflets, with the contents scattered by the force of the blast.

The V-1 was manufactured at various sites in the Reich, but the main production facility was the notorious underground SS slave-labor complex known as "Mittelwerk" at Nordhausen in the Harz Mountains. An estimated total of 24,000 V-1s were built in 1944, with as many as 10,000 built in 1945, though quantities tend to vary from source to source.

The Flying bomb Blitz

The Allies landed on the Normandy beaches on 6 June, a week before the first launch of the V-1, but even as the fighting raged around the beachhead, the flying bomb attacks continued at a brisk pace from the launch sites in the Pas de Calais.

Although the Allies had been expecting the flying bomb, which they codenamed "Diver", the attacks still came as something of a shock. The initial response to the missiles was clumsy and inept. At first, anti-aircraft guns sometimes shot them down over London, causing them to fall into the city even though they might have passed and dropped into an unpopulated area if left alone. The British public reacted to the attacks with a combination of curiosity and fear as the little missiles buzzed overhead, sounding a little like "a Model-T Ford going up a hill" or "like a motor-bike with a two-stroke engine."

San Francisco Chronicle reports V1 attacks on Britain, 1944

The V-1s were originally referred to in the press as "pilotless bombs" or "robot bombers", but Prime Minister Winston Churchill discouraged such language, as they made the weapons sound unstoppable. Eventually, the V-1s became known as "buzz bombs" from the engine sound, or particularly "doodlebugs", a name invented by New Zealander airmen who thought they sounded like a loud buzzing bug of their homeland.

Although the flying bombs were inaccurate, the Germans were launching enough of them to cause severe damage, and the random nature of the attacks was unnerving. Sometimes a flying bomb acted capriciously, shutting off its engine and then restarting it again, or even turning around and flying back the way it came. In fact, one made a U-turn shortly after launching and landed with a tremendous explosion near a command post that Hitler was scheduled to visit.

Sometimes they seemed deadly accurate, leading some to believe they had a precision guidance system. One hit the headquarters of General Dwight Eisenhower, the Supreme Allied Commander. The worst incident occurred on 20 June 1944, when one hit the Guard's Chapel attached to Wellington Barracks, not far from Buckingham Palace, killing 119 and wounding 141. Even when they caused no great loss of life, the flying bombs destroyed historic landmarks, as well as many homes.

 

Churchill was enraged at the attacks, and urged that poison gases be dropped on German cities in retaliation. The RAF responded that such a measure would likely be less effective than the air attacks with high explosive and incendiary bombs already in progress. Churchill was forced to reluctantly abandon his suggestion, which was just as well because the Germans were in a position to more than retaliate in kind. While the Germans thought the Allies had nerve gases and were keeping them a secret, the Allies had no idea such things existed.

German propaganda trumpeted that British citizens were streaming out of London at a rapid rate. In fact, youngsters were being evacuated to the countryside where they were generally out of harm's way, but at the same time workers were coming into the city to help repair the damage, and despite the terror of flying bombs falling out of the sky, the city's inhabitants generally went about their business.

Lookouts were posted on top of factories watch for flying bombs headed their way, and to sound an alarm when necessary so the workers could seek shelter. A popular department store announced that their basement was fitted as an air-raid shelter with a capacity of 1,500 people, and the establishment was equipped to give shoppers warning and all-clear signals.

Fighting the Flying bomb

The initial British defence against the flying bomb attacks was uncoordinated and ineffective. Fighter patrols attempting to intercept the missiles were poorly organized. The flying bombs were small and came in fast, at an altitude where a pilot could have trouble picking them out of the ground clutter. The altitude was also too high for light antiaircraft guns, but still low enough to evade long-range radar detection.

Gloster Meteor   The Gloster Meteor's maiden flight took place at Cranwell, Lincolnshire on 5 March 1943 with Michael Daunt at the controls. The new aircraft was powered by two Halford H.1 turbojets producing 2,300 lb (10.2 kN) thrust each. Eight prototypes were built testing different engine types finally the 1,700 lb (7.5 kN) thrust Rolls-Royce Welland was selected and twenty pre-production jets were built designated Meteor I. The Meteor II never materialized so the Meteor III became the first true production version, the first 15 having Welland engines the rest 2,000 lb (8.9 kN) thrust Derwent 1 turbojets in short nacelles.   No. 616 Squadron received the jet fighter first and flew its first combat sorties on 27 July 1944 against V-1 buzz bombs. On 4 August 1944 came the first victory when Flying Officer T.D. Dean sent a V-1 buzz bomb diving out of control by tipping it with his wing after he discovered his guns were jammed.   On 17 July 1945 the Meteor IV took to the air for the first time powered by two 3,500 lb (15.5 kN) thrust Derwent 5 engines in long nacelles. To add stiffeness to the wings without a major redesign 34 inches (87 cm) was clipped off each wing from the 9th aircraft onwards, thereby increasing the rate of roll but also take-off and landing speeds.   Some 200 Meteor jets were built by war's end.

The first useful measure was to assign interception of the flying bombs to aircraft that had the speed to catch them, such as late-mark Supermarine Spitfires, Hawker Tempests, or Merlin-powered North American P-51s. When the new Gloster Meteor jet fighters reached operational units, they were also assigned to intercept flying bombs, though their flight endurance was less than a hour and long standing patrols were not possible. The number of flying bombs shot down by the Meteor was small, but these "kills" were played up as a propaganda measure.

While Spitfires and Tempests fought the flying bombs by day, night fighters like the De Havilland Mosquito and the new American Northrop P-61 Black Widow fought them at night. Day fighters flying at night were also able to shoot down some of the flying bombs at night, since the pulsejet engines spewed out a bright burning exhaust.

The Royal Observer Corps (ROC), the British ground-spotter network, was ordered to fire marker rockets in the direction of a flying bomb to alert air patrols. This was the first step in redirecting the network of ROC posts, radar stations, and RAF fighter control centers, or "filter rooms" as they were called, to meet the new threat.

At first, fighter pilots were careful to not approach too closely when firing on the flying bombs, since they feared that the big warhead would detonate and blast them out of the sky, but this didn't prove to be a major problem. Some learned to dive past the nose of the bomb to throw it off course, and then pilots became skilled at "tipping" a V-1 into a crash by slipping their wing underneath one of the bomb's and then rolling over. This was a tricky technique, since making physical contact could damage the fighter. The pilot had to instead generate air pressure to disrupt the V-1's flight.

The fighter patrols proved effective in destroying flying bombs. One fighter pilot, 24-year-old Squadron Leader Joseph Berry, destroyed a total of 60 by the end of the attacks. However, ground-based anti-aircraft defenses proved even more effective.

At the beginning of the flying bomb attacks, London was protected to the southeast by a barrier of 2,000 barrage balloons, captive balloons that trailed cables to present a hazard to low-flying aircraft, and a network of anti-aircraft guns.

Initially, neither defensive barrier made many kills. The barrage balloons did bring down a few flying bombs, though some of the V-1s were fitted with cable cutters. The anti-aircraft guns were constrained by rules of engagement designed to protect fighter patrols from "friendly fire".

In mid-July, a decision was made to move the anti-aircraft guns from the vicinity of London to the coast. This would give the guns a free field of fire, as well as hopefully let them destroy the flying bombs over water where they could not cause damage when they fell.

The relocation was no trivial matter, since the system included not only guns but also ammunition stores, communications centers and lines, control centers, and all the other elements of an air defense network. To compound matters, the anti-aircraft gun network had just completed one reorganization, which involved replacement of older manually-aimed weapons with new power-assisted guns.

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A Hawker Hurricane prepares to "Tip" a V-1

The move was performed with impressive efficiency. The plan was submitted on 13 July 1944; the first heavy anti-aircraft guns were in operation in their new sites on 17 July; and the light guns were all in place by 19 July.

American anti-aircraft gun batteries soon joined in the defensive belt. Even more significantly, the Americans introduced two new wonders of technology to the battle that proved to be particularly effective. The first was was the "SCR-548" gun-laying radar, which was used in conjunction with an analog computer to automatically track and fire on aerial intruders.

The second was the radio proximity fuze, which allowed a shell to explode when it came to within a certain radius of a target, rather than being detonated by a time fuze set before firing. The V-1's straight and level path made it a relatively easy target for the new automated anti-aircraft gun system, and as gun crews became more experience with their new tools, the number of kills rose dramatically.

All these defensive measures had been implemented in haste, and it wasn't until late August that attempts were made to improve the coordination of the fighter patrols and the gun belt. By this time, however, the Allies were overrunning V-1 launch sites in the Pas de Calais and the number of flying bomb attacks dropped dramatically.

A total of about 10,000 flying bombs had been launched against London to that time. The Germans had been setting up launch sites near Cherbourg to launch flying bombs against Plymouth and Bristol, but these sites were captured before they became operational.

 

Last gasp of the Flying bomb

Even though the launch sites were overrun, flying bombs continued to hit England, if in reduced numbers.

Back in early July, a small number of flying bombs attacks were performed on Manchester and Gloucester. Allied leadership was baffled as to where these attacks were coming from, since the range of the V-1 was roughly known, and there was no place near enough for the Germans to set up launch sites that could reach these targets.
 

 

 

 

In fact, the Germans were launching the flying bombs from specially modified Heinkel He-111 bombers, operating from airfields in the Netherlands. Work on this scheme predated the beginning of the flying bomb blitz, and involved removing the He-111's bomb racks and a fuel tank, and installing launching gear and provisions for carrying a V-1 nestled under the left wing. The modified bombers were given the designation "He-111H-22".

 

 

 

This proved to be a risky business, since the flying bomb was very heavy and could be lethally tricky to launch. 1,200 V-1s were launched in this fashion, with the loss of 77 bombers. Twelve bombers were lost on two missions alone simply due to the premature detonation of the V-1's warhead after the He-111 left the runway.

Air launch was abandoned in mid-January 1945, due to the high attrition and the advance of Allied forces. However, the Germans were not quite done with this game, having developed a new version of the V-1 with a range of 400 kilometers (250 miles) by reducing the size of the warhead and increasing the size of the fuel tank.

They launched about 275 of these long-range flying bombs against Britain from the Netherlands in March 1945. British defenses were able to adjust to these last-gasp attacks, and the looming defeat of the Reich ended the campaign for good at the end of March. V-2 rocket attacks against England, which had begun the previous September, also slowly fizzled out.

During this last phase of the flying-bomb battle, the German Wehrmacht also launched as many as 9,000 V-1s against continental European targets, particularly the Belgian port city of Antwerp and the neighbouring city of Liege, in hopes of interrupting the flow of Allied supplies to their advancing armies. These attacks faded out in March as well.

The Germans also considered launching V-1s from the back of the Arado Ar-234 jet bomber, using an odd rack that swiveled the missile up away from the aircraft at launch. This project does not seem to have gone past the paper stage.

 

 

One of the unusual side stories of the flying-bomb campaign was development of a piloted "suicide" V-1. The details of this weapon are obscure and the documentation contradictory.

In late 1943, the Germans had experimented with "manned missiles", in which pilots would point their aircraft at a ground target and bail out. Experiments along this line were performed with Focke-Wulf FW-190 and pulsejet-powered Messerschmitt Me-328 fighters, but proved unsuccessful.

In May 1944, SS Hauptsturmführer Otto Skorzeny, Germany's brilliant and ruthless commando leader, proposed using the V-1 for this job. Within two weeks, prototypes of variants of the manned weapon, known as "Reichenberg", were built, with designations "R-I" through "R-IV".

The R-I and R-II were glider trainers and lacked engines. The R-I was a single-seat trainer, while the R-II was a two-seat trainer with dual cockpits. The R-III was a two-seat powered trainer, while the R-IV was the operational weapon. About 175 R-IVs were built, and a group of volunteers was organized to fly them. The piloted flying bombs were to be launched by bombers of "KG-200", the Luftwaffe special operations unit.

Selbstopfer (German for self-sacrifice) was a late-World War II German project to develop a "smart weapon" for attacking high-value targets such as bridges and command centers. First proposed by Otto Skorzeny, leader of the German commandos, and Hanna Reitsch, the famous test pilot, they suggested using converted V1 Flying Bombs with a tiny cockpit on top, with the "smarts" being provided by the pilot. About 100 pilots drawn from Skorzeny's KG 200 were trained, and about 175 of the modified V-1 (named Fieseler Fi 103 R Reichenberg) were built. Unlike the somewhat similar Japanese Kamikaze Ohka, pilots of the new Fi 103 R were intended to bail out just prior to impact, although in reality this would be difficult because of the cramped cockpit, the sharp angle of the final dive, and the fact that the cockpit was located just below the pulsejet intake.   Testing was carried out by KG 200 on several occasions, dropped from Heinkel He 111 bombers, with Reitsch herself piloting an unpowered version equipped with a wooden landing skid. Several stories claim operational use, but it appears highly unlikely that the weapon was ever used in combat.   Some other Nazi secret weapons projects involved near-suicide missions like the Bachem Ba 349 Natter.

In principle, the pilot was to aim the Reichenberg at a target and then bail out. In practice, the weapon lacked an ejection seat, and though provisions were made for escape, getting out of such an aircraft safely as it dived at high speed towards a target was problematic. The volunteer pilots who were to fly the bombs were known as "Selbstopfermänner", or "Suicide Men".

Unsurprisingly, many German officers did not like the scheme. In October 1944, a new commander named Werner Baumbach was appointed to KG-200, and he preferred Mistel to Reichenberg. The Germans had little enthusiasm for kamikaze missions. In fact, some sources say that the piloted V-1s were originally designed strictly as flight test machines, but it is difficult to fit that into the other parts of the story as they are recorded.

Along with the Reichenberg, another interesting dead-end adaptation of the V-1 was its use as an external fuel tank that could be towed behind an aircraft by a long pipe, with the pipe acting as both tow bar and fuel connection. The scheme was evaluated with an Ar-234 jet bomber, but never got beyond preliminary tests.

The effectiveness of the V-1 is debatable. Detractors point out that the V-1 was far too inaccurate to be considered a militarily effective weapon. It was a weapon of mass terror that struck almost at random.

It did prove undeniably destructive, inflicting almost 46,000 casualties, with over 5,000 people killed outright, destroying 130,000 homes, and damaging 750,000 more. However, it had no real effect on the outcome of the war, and absorbed resources that might have been better used in the defense of the Reich.

Others point out that the weapon was cheap to build and tied up a disproportionate amount of Allied resources. Though this was true, the Allies had the resources, and it is questionable that the V-1 prolonged the war by any significant length of time.

 

USAAF JB-2 / JB-1

Despite the V-1's limitations, the US military was very interested in it. In contrast to the bumbling American efforts in radio-controlled flying bombs such as the BQ weapons, the German V-1 looked pretty good, and in July 1944 captured V-1 components were shipped to Wright-Patterson Field in Ohio for evaluation. Within three weeks, the USAAF and American industry had built their own V-1, which was designated the "Jet Bomb 2 (JB-2)".

In August, the USAAF placed an order for 1,000 JB-2s with improved guidance systems: Ford built the pulse-jet engine, designated "PJ-31"; Republic built the airframe; and other manufacturers built the control systems, launch rockets, launch frames, and remaining components.

The JB-2s were launched off a rail with a solid rocket booster, in contrast to the somewhat complicated steam catapult system used by the Germans. Two versions were built, one with a gyroscopic guidance system like that used with the V-1, and the other with a radio-radar guidance system. The USAAF then experimented with air-launching the JB-2. Most of the launches were from a B-17 bomber, though some were performed from B-24s and B-29s. 

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Boeing AGM-86A  based on the original design of the Fi 103