| Aggregat-4 / Vergeltungswaffe-2 | |
|---|---|
Peenemünde Museum replica of V-2 |
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| Type | single stage ballistic missile |
| Place of origin | Germany |
| Service history | |
| In service | 1944–1952 |
| Used by | Germany United States (post-war) Soviet Union (post-war) |
| Production history | |
| Manufacturer | Mittelwerk GmbH (development by Army Research Center Peenemünde) |
| Unit cost | 100,000 RM January 1944, 50,000 RM March 1945[1] |
| Produced | 16 March 1942 |
| Specifications | |
| Weight | 12,500 kg (28,000 lb) |
| Length | 14 m (45 ft 11 in) |
| Diameter | 1.65 m (5 ft 5 in) |
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| Warhead | 980 kg (2,200 lb) Amatol |
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| Wingspan | 3.56 m (11 ft 8 in) |
| Propellant | 3,810 kg (8,400 lb) of 75% ethanol and 25% water + 4,910 kg (10,800 lb) of liquid oxygen |
| Operational range |
320 km (200 mi) |
| Flight altitude | 88 km (55 mi) maximum altitude on long range trajectory, 206 km (128 mi) maximum altitude if launched vertically. |
| Speed | maximum:
at impact:
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| Guidance system |
Gyroscopes to determine direction Müller-type pendulous gyroscopic accelerometer for engine cutoff on most production rockets (10% of the Mittelwerk rockets used a guide beam for cutoff.)[2]:225 |
| Launch platform |
Mobile (Meillerwagen) |
The V-2 rocket (German: Vergeltungswaffe 2, i.e. retaliation weapon 2), technical name Aggregat-4 (A4), was a ballistic missile that was developed at the beginning of the Second World War in Germany, specifically targeted at London and later Antwerp. The liquid-propellant rocket was the world's first long-range[3] combat-ballistic missile[4] and first known human artifact to enter outer space.[5] It was the progenitor of all modern rockets,[6] including those used by the United States and Soviet Union's space programs. During the aftermath of World War II the American, Soviet and British governments all gained access to the V-2's technical designs and the actual German scientists responsible for creating the rockets, via Operation Paperclip, Operation Osoaviakhim and Operation Backfire.[7]
The weapon was presented by Nazi propaganda as a retaliation for the bombers that attacked ever more German cities from 1942 until Germany surrendered.[8]
Over 3,000 V-2s were launched as military rockets by the German Wehrmacht against Allied targets during the war, mostly London and later Antwerp. The attacks resulted in the death of an estimated 7,250 military personnel and civilians, while 12,000 forced labourers were killed producing the weapons.[9]
In the late 1920s, a young Wernher von Braun acquired a copy of Hermann Oberth's book, Die Rakete zu den Planetenräumen (The Rocket into Interplanetary Space).[10] Starting in 1930, he attended the Technical University of Berlin, where he assisted Oberth in liquid-fueled rocket motor tests.[10] Von Braun was working on his creative doctorate when the Nazi Party gained power in Germany.[11] An artillery captain, Walter Dornberger, arranged an Ordnance Department research grant for von Braun, who from then on worked next to Dornberger's existing solid-fuel rocket test site at Kummersdorf.[11] Von Braun's thesis, Construction, Theoretical, and Experimental Solution to the Problem of the Liquid Propellant Rocket (dated 16 April 1934), was kept classified by the German army and was not published until 1960.[12] By the end of 1934, his group had successfully launched two rockets that reached heights of 2.2 and 3.5 km (1.4 and 2.2 mi).[11]
At the time, Germany was highly interested in American physicist Robert H. Goddard's research. Before 1939, German scientists occasionally contacted Goddard directly with technical questions.[11] Von Braun used Goddard's plans from various journals and incorporated them into the building of the Aggregat (A) series of rockets.[11]
Following successes at Kummersdorf with the first two Aggregate series rockets, Wernher von Braun and Walter Riedel began thinking of a much larger rocket in the summer of 1936,[13] based on a projected 25-metric-ton-thrust engine.
After the A-4 project was postponed due to unfavourable aerodynamic stability testing of the A-3 in July 1936,[14][15] von Braun specified the A-4 performance in 1937,[16] and A-4 design and construction was ordered c1938/1939.[17] During 28–30 September 1939, Der Tag der Weisheit (English: the day of wisdom) conference met at Peenemünde to initiate the funding of university research to solve rocket problems.[13]:40 By late 1941, the Army Research Center at Peenemünde possessed the technologies essential to the success of the A-4. The three key technologies for the A-4 were large liquid-fuel rocket engines, supersonic aerodynamics, gyroscopic guidance and rudders in jet control.[2] At the time, Adolf Hitler was not particularly impressed by the V-2; he pointed out that it was merely an artillery shell with a longer range and much higher cost.[18]
In early September 1943, von Braun promised the Long-Range Bombardment Commission[2]:224 that the A-4 development was 'practically complete/concluded',[15]:135 but even by the middle of 1944, a complete A-4 parts list was still unavailable.[2]:224 Hitler was sufficiently impressed by the enthusiasm of its developers, and needed a "wonder weapon" to maintain German morale,[18] so authorized its deployment in large numbers.[19]
The V-2s were constructed at the Mittelwerk site by prisoners from Mittelbau-Dora, the concentration camp where an estimated 20,000 people died during the war. Of these, 9,000 died from exhaustion and collapse, 350 were hanged (including 200 executed for acts of sabotage) and the remainder were either shot or died from disease or starvation.[20][21]
The A-4 used a 75% ethanol/water mixture for fuel and liquid oxygen (LOX) for oxidizer.[22]
At launch the A-4 propelled itself for up to 65 seconds on its own power, and a program motor controlled the pitch to the specified angle at engine shutdown, from which the rocket continued on a ballistic free-fall trajectory. The rocket reached a height of 80 km (50 mi) after shutting off the engine.[23]
The fuel and oxidizer pumps were steam turbines, and the steam was produced by concentrated hydrogen peroxide with Sodium permanganate catalyst. Both the alcohol and oxygen tanks were an aluminium-magnesium alloy.[1]
The combustion burner reached a temperature of 2500–2700 °C (4500 – 4900 °F). The alcohol-water fuel was pumped along the double wall of the main combustion burner. This regenerative cooling heated the fuel and cooled the chamber. The fuel was then pumped into the main burner chamber through 1,224 nozzles, which assured the correct mixture of alcohol and oxygen at all times. Small holes also permitted some alcohol to escape directly into the combustion chamber, forming a cooled boundary layer that further protected the wall of the chamber, especially at the throat where the chamber was narrowest. The boundary layer alcohol ignited in contact with the atmosphere, accounting for the long, diffuse exhaust plume. By contrast, later, post-V2 engine designs not employing this alcohol boundary layer cooling show a translucent plume with shock diamonds.
The V-2 was guided by four external rudders on the tail fins, and four internal graphite vanes at the exit of the motor. The LEV-3 guidance system consisted of two free gyroscopes (a horizon and a vertical) for lateral stabilization, and a PIGA accelerometer to control engine cutoff at a specified velocity. The V-2 was launched from a pre-surveyed location, so the distance and azimuth to the target were known. Fin 1 of the missile was aligned to the target azimuth.[24] Some later V-2s used "guide beams", radio signals transmitted from the ground, to keep the missile on course, but the first models used a simple analog computer that adjusted the azimuth for the rocket, and the flying distance was controlled by the timing of the engine cut-off, "Brennschluss", ground controlled by a Doppler system or by different types of on-board integrating accelerometers. The rocket stopped accelerating and soon reached the top of the approximately parabolic flight curve.
Dr. Friedrich Kirchstein of Siemens of Berlin developed the V-2 radio-control for motor-cut-off (German: Brennschluss).[15]:28,124 For velocity measurement, Professor Wolman of Dresden created an alternative of his Doppler[25]:18 tracking system in 1940–41, which used a ground signal transponded by the A-4 to measure the velocity of the missile.[2]:103 By 9 February 1942, Peenemünde engineer de Beek had documented the radio interference area of a V-2 as 10,000 meters around the “Firing Point”,[26] and the first successful A-4 flight on 3 October 1943, used radio control for Brennschluss.[14]:12 Although, Hitler commented on 22 September 1943, that "It is a great load off our minds that we have dispensed with the radio guiding-beam; now no opening remains for the British to interfere technically with the missile in flight",[15]:138 about 20% of the operational V-2 launches were beam-guided.[14]:12 The Operation Pinguin V-2 offensive began on 8 September 1944, when Lehr- und Versuchsbatterie No. 444[25]:51–2 (English: Training and Testing Battery 444) launched a single rocket guided by a radio beam directed at Paris.[26]:47 Wreckage of combat V-2s occasionally contained the transponder for velocity and fuel cutoff.[13]:259–60
The painting of the operational V-2s was mostly a camouflage ragged pattern with several variations, but at the end of the war a plain olive green rocket also appeared. During tests, the rocket was painted in a characteristic black-and-white chessboard pattern, which aided in determining if the rocket was spinning around its longitudinal axis.
The original German designation of the rocket was "V2", not "V-2". The first English translation of the book V2 – Der Schuss Ins Weltall (English: "V2– The Shot into Space"), by Walter Dornberger,[27] was published in England by Hurst and Blackett in 1954 and titled V2. In that book, the rocket is called the "V2".[28] In the U.S. edition, published by Viking in 1954 and titled V-2, the rocket is called the "V-2".[14] The text appears to be otherwise identical. Common usage now sees the rocket called the V-2.
The first successful test flight was on 3 October 1942:
This third day of October, 1942, is the first of a new era in transportation, that of space travel...
— Speech at Peenemünde, Walter Dornberger, 3 October 1942[14]17
Two test launches were recovered by the Allies: the Bäckebo rocket which landed in Sweden on 13 June 1944 and one recovered by Polish resistance on 30 May 1944[29] from Blizna and transported to the UK during Operation Most III.
Test launches of V-2 rockets (Aggregate-4) were made at Peenemünde, Blizna and Tuchola Forest, and after the war, at Cuxhaven, White Sands Proving Grounds, Cape Canaveral and Kapustin Yar.
Various problems were identified during V-2 development and testing:
Through mid-March 1944, only 4 of the 26 successful Blizna launches had satisfactorily reached the Sarnaki target area[26]:112, 221–222, 282 due to in-flight breakup (Luftzerleger) on entry into the atmosphere.[30]:100 Initially excessive alcohol tank pressure was suspected, and by April 1944 after 5 months of test firings, the cause was still not determined. Major-General Rossmann, the Army Weapons Office department chief, recommended stationing observers in the target area – cMay/June, Walter Dornberger and Wernher von Braun set up a camp at the centre of the Poland target zone.[2]: After moving to the Heidekraut,[13]:172,173 SS Mortar Battery 500 of the 836th Artillery Battalion (Motorized) was ordered[26]:47 on 30 August[25] to begin test launches of eighty 'sleeved' rockets.[15]:281 Testing confirmed the so-called 'tin trousers' – a tube designed to strengthen the forward end of the rocket cladding—reduced the likelihood of airbursts.[30]:100
A production line was nearly ready at Peenemünde when the Operation Hydra attack caused the Germans to move production to the Mittelwerk in the Kohnstein where 5,200 V-2 rockets were built.[31]
| Period of Production | Production |
|---|---|
| Up to 15 Sep 1944 | 1900 |
| 15 Sep to 29 Oct 1944 | 900 |
| 29 Oct to 24 Nov 1944 | 600 |
| 24 Nov to 15 Jan 1945 | 1100 |
| 15 Jan to 15 Feb 1945 | 700 |
| Total | 5200 |
Following Operation Crossbow bombing, initial plans for launching from the massive underground Watten and Wizernes bunkers or from fixed pads such as near the Chateau du Molay[32] were dropped in favour of mobile launching. Eight main storage dumps were planned and four had been completed by July 1944 (the one at Mery-sur-Oise was begun in August 1943 and completed by February 1944).[33] The missile could be launched practically anywhere, roads running through forests being a particular favourite. The system was so mobile and small that not one Meillerwagen was caught in action by Allied aircraft, although Raymond Baxter described flying over a site during a launch and his wingman firing at the missile without hitting it.
It was estimated that a sustained rate of 350 V-2s could be launched per week, with 100 per day at maximum effort, given sufficient supply of the rockets.[34]
After Hitler's 29 August declaration to begin V-2 attacks as soon as possible, the offensive began on 8 September 1944 with a single launch at Paris, which caused modest damage near Porte d'Italie,[13]:218,220,467. Two more launches by the 485th followed, including one from The Hague against London on the same day at 6:43 p.m.[15]:285 – the first landed at Chiswick, killing 63-year-old Mrs. Ada Harrison, 3-year-old Rosemary Clarke, and Sapper Bernard Browning on leave from the Royal Engineers.[16]:11 Upon hearing the double-crack of the supersonic rocket (London's first-ever), Duncan Sandys and Reginald Victor Jones looked up from different parts of the city and exclaimed "That was a rocket!", and a short while after the double-crack, the sky was filled with the sound of a heavy body rushing through the air.[15]:286 The Germans themselves finally announced the V-2 on 8 November 1944 and only then, on 10 November 1944, did Winston Churchill inform Parliament, and the world, that England had been under rocket attack "for the last few weeks".
Over the next few months the number of V-2s fired was at least 3,172, distributed over the various targets as follows:
An estimated 2,754 civilians were killed in London by V-2 attacks with another 6,523 injured,[35] which is two people killed per V-2 rocket. However, this understates the potential of the V-2, since many rockets were misdirected and exploded harmlessly. Accuracy increased over the course of the war, particularly on batteries where Leitstrahl-Guide Beam apparatus was installed.[36] Missile strikes were often devastating, causing large numbers of deaths—160 killed and 108 seriously injured in one explosion on 25 November 1944 in mid-afternoon, striking a Woolworth's department store in New Cross, south-east London.
After these deadly results, British intelligence leaked falsified information implying that the rockets were over-shooting their London target by 10 to 20 miles. This tactic worked and for the remainder of the war most landed in Kent due to erroneous recalibration.[37]
The final two rockets exploded on 27 March 1945. One of these was the last V-2 to kill a British civilian: Mrs. Ivy Millichamp, aged 34, killed in her home in Kynaston Road, Orpington in Kent,[38] evidencing the German re-calibration.
Antwerp, Belgium was also the target for a large number of V-weapon attacks from October, 1944 through March, 1945, leaving 1,736 dead and 4,500 injured in greater Antwerp. Thousands of buildings were damaged or destroyed as the city was struck by 590 direct hits. The largest loss of life in a single attack came on December 16, 1944, when the roof of a crowded cinema was struck, leaving 567 dead and 291 injured.[39]
A scientific reconstruction carried out in 2010 demonstrated that the V-2 creates a crater 20 m wide and 8 m deep, throwing up around 3,000 tons of material into the air.[37]
Unlike the V-1, the V-2's speed and trajectory made it invulnerable to anti-aircraft guns and fighters, as it dropped from an altitude of 100–110 km (62–68 mi) at up to four times the speed of sound (approximately 3550 km/h). A plan was proposed whereby the missile would be detected by radar, its terminal trajectory calculated, and the area along that trajectory saturated by large-caliber anti-aircraft guns. The plan was dropped after operations research indicated that the likely number of malfunctioning artillery shells falling to the ground would do more damage than the V-2 itself.[40]
The defence against the V-2 campaign was to destroy the launch infrastructure—expensive in terms of bomber resources and casualties—or to cause the Germans to "aim" at the wrong place through disinformation. The British were able to convince the Germans to direct V-1s and V-2s aimed at London to less populated areas east of the city. This was done by sending false impact reports via the German espionage network in Britain, which was controlled by the British (the Double Cross System).
There is a record of one V-2, fortuitously observed at launch from a passing American B-24 Liberator, being shot down by .50 caliber machine-gun fire.[41]
The limitations of any countermeasures can be understood by two facts: 20 seconds after launch, a V-2 was out of reach; the time from launch to impact in London being merely 3 minutes.
Ultimately the most successful countermeasure was the Allied advance that forced the launchers back beyond range.
On 3 March 1945 the Allies attempted to destroy V-2s and launching equipment near The Hague by a large-scale bombardment, but due to navigational errors the Bezuidenhout quarter was destroyed, killing 500 Dutch civilians.
The German V-weapons (V-1 and V-2) cost $3 billion (wartime dollars) and was more costly than the Manhattan Project that produced the atomic bomb ($1.9 billion).[13]:178 6,048 V-2s were built, at a cost of approximately 100,000 Reichsmarks (GB£2,370,000 (2011)) each; 3,225 were launched. SS General Hans Kammler, who as an engineer had constructed several concentration camps including Auschwitz, had a reputation for brutality and had originated the idea of using concentration camp prisoners as slave laborers in the rocket program. The V-2 is perhaps the only weapon system to have caused more deaths by its production than its deployment.[42]
"… those of us who were seriously engaged in the war were very grateful to Wernher von Braun. We knew that each V-2 cost as much to produce as a high-performance fighter airplane. We knew that German forces on the fighting fronts were in desperate need of airplanes, and that the V-2 rockets were doing us no military damage. From our point of view, the V-2 program was almost as good as if Hitler had adopted a policy of unilateral disarmament." (Freeman Dyson)[43]
The V-2 consumed a third of Germany's fuel alcohol production and major portions of other critical technologies:[44] to distil the fuel alcohol for one V-2 launch required 30 tons of potatoes at a time when food was becoming scarce.[45] Due to a lack of explosives, concrete was used and sometimes the warhead contained photographic propaganda of German citizens who had died in allied bombing.[18]
The V-2 lacked a proximity fuse, so it could not be set for air burst; it buried itself in the target area before or just as the warhead detonated. This reduced its effectiveness. Furthermore, its early guidance systems were too primitive to hit specific targets and its costs were approximately equivalent to four-engined bombers, which were more accurate (though only in a relative sense), had longer ranges, carried many more warheads, and were reusable. Moreover, it diverted resources from other, more effective programs. Nevertheless, it had a considerable psychological effect because, unlike bombing planes or the V-1 Flying Bomb (which made a characteristic buzzing sound), the V-2 travelled faster than the speed of sound, with no warning before impact, no possibility of defence and there was no risk of attacking pilot and crew casualties.
With the war all but lost, regardless of the factory output of conventional weapons, the Nazis resorted to V-weapons as a tenuous last hope to influence the war militarily (hence Antwerp as V-2 target), as an extension of their desire to "punish" their foes and most importantly to give hope to their supporters with their miracle weapon.[18] The V-2 had no effect on the outcome of the war, but its value, despite its overall ineffectiveness, was in its novelty as a weapon which set the stage for the next 50 years of ballistic military rocketry, culminating with ICBMs during the Cold War and modern space exploration.
A submarine-towed launch platform was tested successfully, making it the prototype for submarine-launched ballistic missiles. The project codename was Prüfstand XII ("Test stand XII"), sometimes called the rocket U-boat. If deployed, it would have allowed a U-boat to launch V-2 missiles against United States cities, though only with considerable effort (and limited effect).[46] Hitler, in July 1944 and Speer, in January 1945, made speeches alluding to the scheme,[47] though Germany did not possess any capability to fulfill these threats. These schemes were met by the Americans with Operation Teardrop.
While interned after the war by the British at CSDIC camp 11, Dornberger was recorded saying that he had begged the Führer to stop the V-weapon propaganda, because nothing more could be expected from one ton of explosive. To this Hitler had replied that Dornberger might not expect more but he certainly did.
According to decrypted messages from the Japanese embassy in Germany, twelve dismantled V-2 rockets were shipped to Japan.[48] These left Bordeaux in August 1944 on the transport U-boats U-219 and U-195, which reached Djakarta in December 1944. A civilian V-2 expert was a passenger on U-234, bound for Japan in May 1945 when the war ended in Europe. The fate of these V-2 rockets is unknown.
Near the end of the war, German scientists were working on chemical and possibly biological weapons to use in the V-2 program. By this stage, the Germans had produced munitions containing nerve agents sarin, soman and tabun; they never used them.
At the end of the war, a race began between the United States and the USSR to retrieve as many V-2 rockets and staff as possible.[49] Three hundred rail-car loads of V-2s and parts were captured and shipped to the United States and 126 of the principal designers, including Wernher von Braun and Walter Dornberger were in American hands. Von Braun, his brother Magnus von Braun and seven others decided to surrender to the United States military (Operation Paperclip) to ensure they were not captured by the advancing Soviets or shot dead by the Nazis to prevent their capture.[50]
In October 1945, British Operation Backfire assembled a small number of V-2 missiles and launched three of them from a site in northern Germany. The engineers involved had already agreed to move to the US when the test firings were complete. The Backfire report remains the most extensive technical documentation of the rocket, including all support procedures, tailored vehicles and fuel composition.
Post-war V-2s launched in secret from Peenemünde may have been responsible for a curious phenomenon known as Ghost rockets, unexplained objects crossing the skies over Sweden and Finland.
In his book My Father's Son, Canadian author Farley Mowat, then a member of the Canadian Army, claims to have obtained a V-2 rocket in 1945 and shipped it back to Canada, where it is alleged to have ended up in the National Exhibition grounds in Toronto. There was a V-2 stored outside at RCAF Station Picton, Ontario in June 1961.
The Canadian Arrow, a competitor for the Ansari X Prize, was based on the aerodynamic design of the V-2.
Operation Paperclip recruited German engineers and Special Mission V-2 transported the captured V-2 parts to the United States. At the close of the Second World War, over 300 rail cars filled with V-2 engines, fuselages, propellant tanks, gyroscopes and associated equipment were brought to the railyards in Las Cruces, New Mexico, so they could be placed on trucks and driven to the White Sands Proving Grounds, also in New Mexico.
In addition to V-2 hardware, the U.S. Government delivered German mechanization equations for the V-2 guidance, navigation and control systems, as well as for advanced development concept vehicles, to U.S. defense contractors for analysis. In the 1950s some of these documents were useful to U.S. contractors in developing direction cosine matrix transformations and other inertial navigation architecture concepts that were applied to early U.S. programs such as the Atlas and Minuteman guidance systems as well as the Navy's Subs Inertial Navigation System.
A committee was formed with military and civilian scientists, to review payload proposals for the reassembled V-2 rockets. This led to an eclectic array of experiments that flew on V-2s and paved the way for American manned space exploration. Devices were sent aloft to sample the air at all levels to determine atmospheric pressures and to see what gases were present. Other instruments measured the level of cosmic radiation.
Only 68 percent of the V-2 trials were considered successful. A supposed V-2 launched on 29 May 1947 landed near Juarez, Mexico and was actually a Hermes B-1 vehicle.[51]
The U.S. Navy attempted to launch a German V-2 rocket at sea—one test launch from the aircraft carrier USS Midway was performed on 6 September 1947 as part of the Navy's Operation Sandy. The test launch was a partial success; the V-2 went off the pad but splashed down in the ocean only some 10 km (6.2 mi) from the carrier. The launch setup on the Midway's deck is notable in that it used foldaway arms to prevent the missile from falling over. The arms pulled away just after the engine ignited, releasing the missile. The setup may look similar to the R-7 launch procedure but in the case of the R-7 the trusses hold the full weight of the rocket, rather than just reacting to side forces.
The PGM-11 Redstone rocket is a direct descendant of the V-2.[52]
The USSR also captured a number of V-2s and staff, letting them set up in Germany for a time. The first work contracts were signed in the middle of 1945. In 1946 (as part of Operation Osoaviakhim) they were obliged to move to Kapustin Yar in the USSR, where Gröttrup headed up a group of just under 250 engineers. The first Soviet missile was the R-1, a duplicate of the V-2. Most of the German team was sent home after that project but some remained to do research until as late as 1951. Unbeknownst to the Germans, work immediately began on larger missiles, the R-2 and R-5, based on extension of the V-2 technology.
Model rocket V-2s are available in many sizes. Since the 1960s Estes Industries has released several versions of the V-2. Currently there are no Estes V-2s in production.
At least 20 V-2s still existed in 2005.
One replica was constructed for the Peenemünde Historical and Technical Information Centre[53] where it is displayed near what remains of the factory where it was built.
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