Aggregate series
Encyclopedia
The Aggregate series was a set of rocket designs developed in 1933–1945 by a research program of Nazi Germany
's army. Its greatest success was the A4, more commonly known as the V-2
. The German word refers to a group of machines working together.
in a Wehrmacht
(German armed forces) research program at Kummersdorf
headed by Walter Dornberger
. The A-1 was the grandfather of most modern rockets. The rocket was 1.4 metres (5 ft) long, 30.5 centimetres (12 in) in diameter, and had a takeoff weight of 150 kilograms (331 lb). The engine, designed by Arthur Rudolph
, used a pressure-fed propellant system burning alcohol
and liquid oxygen
, and produced 300 kgf
(660 lbf
, 2.9 kN) of thrust for 16 seconds. The rocket was stabilized by a 90 pound gyroscope in the nose, but there was concern that this might cause problems with the liquid fuels. Although the engine had been successfully test fired, the first flight attempt blew up on the launching pad. Since the design was thought to be unstable, no further attempts were made, and efforts moved to the A2 design (Gatland 1989, p. 10).
.
At a length of 1.6 metres (5 ft) and thrust of 3 kN from alcohol and liquid oxygen, it was in outline similar to the A1. However, in contrast to the A1, the A2 had the stabilization gyroscopes in the center of the rocket between the alcohol and oxygen tanks, which made it more stable. The rocket weighed 72 kilograms (159 lb) empty, with takeoff weight of 107 kilograms (236 lb). Initial flight testing was done in September 1934 at Kummersdorf.
Two A2s were built for a full out test, and were named after a Wilhelm Busch
cartoon, Max and Moritz
. On December 19 and December 20, 1934 they were launched in front of the Army brass on Borkum
island in the North Sea
. They reached altitudes of 2.2 kilometres (1.4 mi) and 3.5 kilometres (2.2 mi).
a budget of almost one half-million marks for the construction of two new test stands at Kummersdorf. Included were mobile test rigs, small locomotives, and office and storage space. The A3 plans called for a rocket with an inertial guidance system and a 3,300 pound (1500 kg) thrust engine.
In March 1936, Army General Werner von Fritsch
witnessed a static firing of an A3 engine at Kummersdorf, and was sufficiently impressed to lend his support to the rocket program. Like the earlier A1 and A2 rockets, the A3 also used a pressure-fed propellant system, and the same liquid oxygen and 75% alcohol mixture as the earlier designs. It generated its 3,300 pounds of thrust (14.7 kN) for 45 seconds. It used a three-gyroscope system to deflect tungsten-alloy jet vanes. The design was finished and secretly patented in the spring of 1936 and further modifications that made the rocket stable at supersonic velocities were finalized in the autumn.
The first of the Aggregate rockets to be launched
from the Peenemüde area, the initial A3 was sent off on December 4, 1937 as part of Operation Lighthouse
. The first and second launches displayed problems with both premature parachute deployment and engine failure; both crashed close to their takeoff points. The parachute was disabled in the third and fourth rockets, but these, too, experienced engine failures, though the lack of parachute drag allowed them to crash further from the launch site.
According to another source, one A3 reached a maximum downrange of 7.5 miles (12.1 km) and maximum altitude of 11 miles (18 km).
With each launch a failure, von Braun and Dornberger looked for the cause. At first there was some thought of an electrostatic charge
that prematurely set off the parachute, but this was largely disproved. Ultimately, the failures were attributed to the inadequate design of the rocket's experimental inertial guidance system and minor instabilities in the body and fin design.
After this unsuccessful series of launches, the A3 was abandoned and redesigned as the A5. In the meantime, work on the A4 continued.
. Versions of the A4 included the first ballistic missile, the first projectile to reach space
, and were actively used in warfare.
This increase in capability had come through a complete redesign of the A3 engine by Walter Thiel
, known as the A5. It became clearer that von Braun's
designs were turning into real weapons, and Dornberger moved the team from the artillery testing grounds at Kummersdorf (near Berlin
) to a small town, Peenemünde
, on the island of Usedom
on Germany's Baltic
coast, in order to provide more room for testing and greater secrecy. This version was completely reliable, and by 1941 the team had fired about 70 A5 rockets. The first A4 flew in March 1942, flying about 1.6 kilometers (1 mi) and crashing into the water. The second launch reached an altitude of 11 kilometers (7 mi) before exploding. The third rocket, launched on October 3, 1942, followed its trajectory perfectly. It landed 193 kilometers (120 mi) away, and reached a height of 80 kilometers (50 mi).
Production started in 1943 on the rocket, now known as the Vergeltungswaffe 2 (Vengeance Weapon 2) or V-2, at the insistence of Goebbels
' propaganda
ministry. The Allies
were already aware of the weapon — at a test site at Blizna
in Poland
.
The missile testing ground at Blizna was quickly located by the Polish resistance movement, the Armia Krajowa
thanks to reports from local farmers. Armia Krajowa field agents even managed to obtain pieces of the fired rockets, by arriving on the scene before German patrols. In early March 1944, British Intelligence Headquarters
received a report of a Armia Krajowa
agent (code name: ‘Makary’) who had covertly surveyed the Blizna railway line
and observed a freight car
heavily guarded by SS troops
containing ‘an object which, though covered by a tarpaulin, bore every resemblance to a monstrous torpedo’. Subsequently, a plan was formed to make an attempt to capture a whole unexploded V-2 rocket
and transport it to Britain. Around 20 May 1944, a relatively undamaged V-2 rocket fell on the swampy bank of the Bug River
near the village of Sarnaki and local Poles managed to hide it before German arrival. The rocket was then dismantled and smuggled across Poland. In late July 1944, the Polish resistance
(Home Army and V1 and V2
) secretly transported parts of the rocket out of Poland in Operation Most III
(Bridge III), for analysis by British intelligence.
In June 1939, Kurt Patt of the Peenemünde Design Office, proposed wings for converting rocket speed and altitude into aerodynamic lift and range. As the rocket encountered thicker atmosphere on its descent phase, it would execute a pullout and enter a shallow glide, trading speed for distance. Patt also proposed the Flossengeschoss (fin projectile). Both concepts were utilized by Walter Dornberger
when he drafted a memo for presentation to Hitler regarding the "America rocket" on July 31, 1940.
Design studies on the A-9 began in 1940. In addition to its wings, the A-9 would have been somewhat larger than the A-4 and its engine would have produced about 30% more thrust. Following wind tunnel testing of models, the design was subsequently modified to replace the wings with fuselage strakes
, as the tests showed that these provided better lift at supersonic velocities and also solved the problem of transonic shift of the centre of lift.
Development was suspended in 1941, but in 1944 several V-2s were modified to an approximation of the A-9 configuration under the designation A-4b. It was calculated that by fitting wings, the A4's range would be extended to 750 km (466 mi), allowing targets in Britain to be attacked from launch sites within Germany itself. It was intended that following launch the curve of the A-4b's trajectory would become shallower and the rocket would glide toward its target. It was anticipated that interception by enemy aircraft at the end of the glide phase would be virtually impossible as over the target the A-4b was intended to enter a near vertical dive leaving little time for interception.
The A-4b concept was tested by fitting swept back wings to two A-4s launched from Blizna. However, little development work had been carried out and the first launch on 27 December 1944 was a complete failure. The second launch attempt, on 24 January 1945, was partially successful, in that the wing broke off, but the A-4b still managed to become the first winged guided missile to break the sound barrier and attain Mach 4.
engines for air drop testing.
The A5 was 5.825 m (19.1 ft) long, with a diameter of 0.78 m (2.6 ft) and a takeoff weight of 900 kg (1,984.2 lb), and like the A3 was fueled with alcohol with liquid oxygen as an oxidant. The first launch of the A5 took place in the summer of 1938 at Greifswalder Oie
and the first successful guided flights were made in October 1939 in order to test the control systems planned for use in the A4. The A5 reached a ceiling of up to 12 km (7.5 mi).
Some sources indicate that it was also applied to a speculative proposal for a manned reconnaissance version of the A4b winged variant of the A4. This A6 was initially proposed to the German Air Ministry as an uninterceptable reconnaissance craft. It would be launched vertically by rocket, taking it to an apogee of 95 km (59 mi); after re-entering the atmosphere it would enter a supersonic glide phase, when its single ramjet would be ignited. It was hoped that this would provide 15 to 20 minutes of cruise at 2900 km/h (1,802 mph) and would allow the aircraft to return to its base and make a conventional runway landing assisted by a drag chute. However, the Air Ministry had no requirement for such an aircraft and the proposal was rejected. Similar concepts (though unmanned) were produced after the war in the form of the USA's SM-64 Navaho
missile and the USSR's Burya
, both intercontinental cruise missiles with ramjet propulsion.
. The A7 was similar in structure to the A5, but had larger tail unit fins (1.621 m²) in order to obtain greater range in gliding flight. Two unpowered models of the A7 were dropped from airplanes in order to test flight stability; no powered test was ever performed. The finished rocket should have produced a takeoff thrust of 15 kN and a takeoff weight of 1000 kg. The design had a diameter of 0.38 m and a length of 5.91 m.
and Diamant
rocket projects.
Design work on the A10 began in 1940, for a projected first flight to take place in 1946. The initial design was carried out by Ludwig Roth und Graupe and was completed on 29 June 1940. Hermann Oberth worked on the design during 1941, and in December 1941 Walter Thiel proposed that the A10 use an engine composed of six bundled A4 engines, which it was thought would give a total thrust of 180 tonnes.
Work on the A10 was resumed in late 1944 under the Projekt Amerika codename, and the A10's design was amended to incorporate a cluster of 6 A4 combustion chambers feeding into a single expansion nozzle. This was later altered to a massive single chamber and single nozzle. Test stands were constructed at Peenemunde for firings of the 200 tonne thrust motor.
It was considered that existing guidance systems would not be accurate enough over a distance of 5,000 km, and it was decided to make the A9 piloted. The pilot was to be guided on his terminal glide towards the target by radio beacons on U-boats and by automatic weather stations landed in Greenland and Labrador.
The final design of the A10 booster was approximately 65 ft (19.8 m) in height. Powered by a 375000 lbf (1,668.1 kN) thrust rocket burning Diesel oil and nitric acid, during its 50 second burn it would have propelled its A9 second stage to a speed of about 2700 mph (1,207 m/s) and an altitude of 15 mi (24.1 km).
The A11 design was shown by von Braun to US officers in Garmisch-Partenkirchen; the drawing was later published in 1946 by the US Army. The A11 was shown as using six of the large single-chamber engines proposed for the A10 stage, with a modified A10 second stage nested within the A11. The design also showed the winged A9, indicating a gliding landing or bombing mission. To achieve orbit, either a new "kick stage" would have been required, or the A9 would have to have been lightened. In either case, only a payload of approximately 300 kg (661.4 lb) could have been placed in a Low Earth Orbit.
The A12 stage itself would have weighed around 3,500 tonnes fully fuelled, and would have stood 33 m (108.3 ft) high. It was to have been propelled by 50 A10 engines, fuelled by liquid oxygen and alcohol.
Nazi Germany
Nazi Germany , also known as the Third Reich , but officially called German Reich from 1933 to 1943 and Greater German Reich from 26 June 1943 onward, is the name commonly used to refer to the state of Germany from 1933 to 1945, when it was a totalitarian dictatorship ruled by...
's army. Its greatest success was the A4, more commonly known as the V-2
V-2 rocket
The V-2 rocket , technical name Aggregat-4 , 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 combat-ballistic missile and first known...
. The German word refers to a group of machines working together.
A1
The A1 was the first rocket design in the Aggregate series. It was designed in 1933 by Wernher von BraunWernher von Braun
Wernher Magnus Maximilian, Freiherr von Braun was a German rocket scientist, aerospace engineer, space architect, and one of the leading figures in the development of rocket technology in Nazi Germany during World War II and in the United States after that.A former member of the Nazi party,...
in a Wehrmacht
Wehrmacht
The Wehrmacht – from , to defend and , the might/power) were the unified armed forces of Nazi Germany from 1935 to 1945. It consisted of the Heer , the Kriegsmarine and the Luftwaffe .-Origin and use of the term:...
(German armed forces) research program at Kummersdorf
Kummersdorf
Kummersdorf is the name of an estate near Luckenwalde at , around 25km south of Berlin, in the Brandenburg region of Germany. Until 1945 Kummersdorf hosted the weapon office of the German Army which ran a development centre for future weapons as well as an artillery range.In 1929 the Army Weapons...
headed by Walter Dornberger
Walter Dornberger
Major-General Dr Walter Robert Dornberger was a German Army artillery officer whose career spanned World Wars I and II. He was a leader of Germany's V-2 rocket program and other projects at the Peenemünde Army Research Center....
. The A-1 was the grandfather of most modern rockets. The rocket was 1.4 metres (5 ft) long, 30.5 centimetres (12 in) in diameter, and had a takeoff weight of 150 kilograms (331 lb). The engine, designed by Arthur Rudolph
Arthur Rudolph
Arthur Louis Hugo Rudolph was a German rocket engineer and member of the Nazi party who played a key role in the development of the V-2 rocket. After World War II he was brought to the United States, subsequently becoming a pioneer of the United States space program. He worked for the U.S...
, used a pressure-fed propellant system burning alcohol
Alcohol
In chemistry, an alcohol is an organic compound in which the hydroxy functional group is bound to a carbon atom. In particular, this carbon center should be saturated, having single bonds to three other atoms....
and liquid oxygen
Liquid oxygen
Liquid oxygen — abbreviated LOx, LOX or Lox in the aerospace, submarine and gas industries — is one of the physical forms of elemental oxygen.-Physical properties:...
, and produced 300 kgf
Kilogram-force
A kilogram-force , or kilopond , is a gravitational metric unit of force. It is equal to the magnitude of the force exerted by one kilogram of mass in a gravitational field...
(660 lbf
Pound-force
The pound force is a unit of force in some systems of measurement including English engineering units and British gravitational units.- Definitions :...
, 2.9 kN) of thrust for 16 seconds. The rocket was stabilized by a 90 pound gyroscope in the nose, but there was concern that this might cause problems with the liquid fuels. Although the engine had been successfully test fired, the first flight attempt blew up on the launching pad. Since the design was thought to be unstable, no further attempts were made, and efforts moved to the A2 design (Gatland 1989, p. 10).
A2
The A2 was designed in 1934 by von Braun under the program at Kummersdorf headed by Walter DornbergerWalter Dornberger
Major-General Dr Walter Robert Dornberger was a German Army artillery officer whose career spanned World Wars I and II. He was a leader of Germany's V-2 rocket program and other projects at the Peenemünde Army Research Center....
.
At a length of 1.6 metres (5 ft) and thrust of 3 kN from alcohol and liquid oxygen, it was in outline similar to the A1. However, in contrast to the A1, the A2 had the stabilization gyroscopes in the center of the rocket between the alcohol and oxygen tanks, which made it more stable. The rocket weighed 72 kilograms (159 lb) empty, with takeoff weight of 107 kilograms (236 lb). Initial flight testing was done in September 1934 at Kummersdorf.
Two A2s were built for a full out test, and were named after a Wilhelm Busch
Wilhelm Busch
Wilhelm Busch was an influential German caricaturist, painter, and poet who is famed for his satirical picture stories with rhymed texts....
cartoon, Max and Moritz
Max and Moritz
Max and Moritz is a German language illustrated story in verse. This highly inventive, blackly humorous tale, told entirely in rhymed couplets, was written and illustrated by Wilhelm Busch and published in 1865...
. On December 19 and December 20, 1934 they were launched in front of the Army brass on Borkum
Borkum
Borkum is an island and a municipality in the Leer District in Lower Saxony, northwestern Germany.-Geography:Borkum is bordered to the west by the Westerems strait , to the east by the Osterems strait, to the north by the North Sea, and to the south by the Wadden Sea...
island in the North Sea
North Sea
In the southwest, beyond the Straits of Dover, the North Sea becomes the English Channel connecting to the Atlantic Ocean. In the east, it connects to the Baltic Sea via the Skagerrak and Kattegat, narrow straits that separate Denmark from Norway and Sweden respectively...
. They reached altitudes of 2.2 kilometres (1.4 mi) and 3.5 kilometres (2.2 mi).
A3
Development of the A3 can be traced at least to February 1935 when Major Ernst Ritter von Horstig sent General Karl BeckerKarl Heinrich Emil Becker
Karl Heinrich Emil Becker was a German weapons engineer and artillery general. He advocated and implemented close ties of the military to science for purposes of advanced weapons development...
a budget of almost one half-million marks for the construction of two new test stands at Kummersdorf. Included were mobile test rigs, small locomotives, and office and storage space. The A3 plans called for a rocket with an inertial guidance system and a 3,300 pound (1500 kg) thrust engine.
In March 1936, Army General Werner von Fritsch
Werner von Fritsch
Werner Thomas Ludwig Freiherr von Fritsch was a prominent Wehrmacht officer, member of the German High Command, and the second German general to be killed during World War II.-Early life:...
witnessed a static firing of an A3 engine at Kummersdorf, and was sufficiently impressed to lend his support to the rocket program. Like the earlier A1 and A2 rockets, the A3 also used a pressure-fed propellant system, and the same liquid oxygen and 75% alcohol mixture as the earlier designs. It generated its 3,300 pounds of thrust (14.7 kN) for 45 seconds. It used a three-gyroscope system to deflect tungsten-alloy jet vanes. The design was finished and secretly patented in the spring of 1936 and further modifications that made the rocket stable at supersonic velocities were finalized in the autumn.
The first of the Aggregate rockets to be launched
Rocket launch
A rocket launch is the takeoff phase of the flight of a rocket. Launches for orbital spaceflights, or launches into interplanetary space, are usually from a fixed location on the ground, but may also be from a floating platform such as the San Marco platform, or the Sea Launch launch...
from the Peenemüde area, the initial A3 was sent off on December 4, 1937 as part of Operation Lighthouse
Operation Lighthouse (1937)
Operation Lighthouse was the name given to the failed experimental launch of four Aggregate 3 liquid-fuel rockets by Wernher von Braun and Walter Dornberger on the German island of Greifswalder Oie in December 1937.-Background and preparation:...
. The first and second launches displayed problems with both premature parachute deployment and engine failure; both crashed close to their takeoff points. The parachute was disabled in the third and fourth rockets, but these, too, experienced engine failures, though the lack of parachute drag allowed them to crash further from the launch site.
According to another source, one A3 reached a maximum downrange of 7.5 miles (12.1 km) and maximum altitude of 11 miles (18 km).
With each launch a failure, von Braun and Dornberger looked for the cause. At first there was some thought of an electrostatic charge
Electrostatics
Electrostatics is the branch of physics that deals with the phenomena and properties of stationary or slow-moving electric charges....
that prematurely set off the parachute, but this was largely disproved. Ultimately, the failures were attributed to the inadequate design of the rocket's experimental inertial guidance system and minor instabilities in the body and fin design.
After this unsuccessful series of launches, the A3 was abandoned and redesigned as the A5. In the meantime, work on the A4 continued.
Specifications
- Length: 6.74 meters (22.1 ft)
- Diameter: 0.68 meters (2.2 ft)
- Finspan: 0.93 meters (3.1 ft)
- Launch mass: 748 kilograms (1650 lb)
- Fuel: ethanol and liquid oxygenLiquid oxygenLiquid oxygen — abbreviated LOx, LOX or Lox in the aerospace, submarine and gas industries — is one of the physical forms of elemental oxygen.-Physical properties:...
. - Liftoff thrust: 14.7 kN (1500 kgfKilogram-forceA kilogram-force , or kilopond , is a gravitational metric unit of force. It is equal to the magnitude of the force exerted by one kilogram of mass in a gravitational field...
).
A4 (V-2 rocket)
The A4 was a full-sized design with a range of about 175 kilometers (109 mi), a top altitude of 80 kilometers (50 mi) and a payload of about a tonneTonne
The tonne, known as the metric ton in the US , often put pleonastically as "metric tonne" to avoid confusion with ton, is a metric system unit of mass equal to 1000 kilograms. The tonne is not an International System of Units unit, but is accepted for use with the SI...
. Versions of the A4 included the first ballistic missile, the first projectile to reach space
Space
Space is the boundless, three-dimensional extent in which objects and events occur and have relative position and direction. Physical space is often conceived in three linear dimensions, although modern physicists usually consider it, with time, to be part of a boundless four-dimensional continuum...
, and were actively used in warfare.
This increase in capability had come through a complete redesign of the A3 engine by Walter Thiel
Walter Thiel
Dr Walter Thiel was a German rocket scientist.He was the third civilian hired by Walter Dornberger for German research at Kummersdorf on November 1, 1932, , and in 1936, transferred to Dornberger's new rocket section...
, known as the A5. It became clearer that von Braun's
Wernher von Braun
Wernher Magnus Maximilian, Freiherr von Braun was a German rocket scientist, aerospace engineer, space architect, and one of the leading figures in the development of rocket technology in Nazi Germany during World War II and in the United States after that.A former member of the Nazi party,...
designs were turning into real weapons, and Dornberger moved the team from the artillery testing grounds at Kummersdorf (near Berlin
Berlin
Berlin is the capital city of Germany and is one of the 16 states of Germany. With a population of 3.45 million people, Berlin is Germany's largest city. It is the second most populous city proper and the seventh most populous urban area in the European Union...
) to a small town, Peenemünde
Peenemünde
The Peenemünde Army Research Center was founded in 1937 as one of five military proving grounds under the Army Weapons Office ....
, on the island of Usedom
Usedom
Usedom is a Baltic Sea island on the border between Germany and Poland. It is situated north of the Szczecin Lagoon estuary of the River Oder in Pomerania...
on Germany's Baltic
Baltic Sea
The Baltic Sea is a brackish mediterranean sea located in Northern Europe, from 53°N to 66°N latitude and from 20°E to 26°E longitude. It is bounded by the Scandinavian Peninsula, the mainland of Europe, and the Danish islands. It drains into the Kattegat by way of the Øresund, the Great Belt and...
coast, in order to provide more room for testing and greater secrecy. This version was completely reliable, and by 1941 the team had fired about 70 A5 rockets. The first A4 flew in March 1942, flying about 1.6 kilometers (1 mi) and crashing into the water. The second launch reached an altitude of 11 kilometers (7 mi) before exploding. The third rocket, launched on October 3, 1942, followed its trajectory perfectly. It landed 193 kilometers (120 mi) away, and reached a height of 80 kilometers (50 mi).
Production started in 1943 on the rocket, now known as the Vergeltungswaffe 2 (Vengeance Weapon 2) or V-2, at the insistence of Goebbels
Joseph Goebbels
Paul Joseph Goebbels was a German politician and Reich Minister of Propaganda in Nazi Germany from 1933 to 1945. As one of Adolf Hitler's closest associates and most devout followers, he was known for his zealous oratory and anti-Semitism...
' propaganda
Propaganda
Propaganda is a form of communication that is aimed at influencing the attitude of a community toward some cause or position so as to benefit oneself or one's group....
ministry. The Allies
Allies
In everyday English usage, allies are people, groups, or nations that have joined together in an association for mutual benefit or to achieve some common purpose, whether or not explicit agreement has been worked out between them...
were already aware of the weapon — at a test site at Blizna
Blizna
Blizna is a village in the administrative district of Gmina Ostrów, within Ropczyce-Sędziszów County, Subcarpathian Voivodeship, in south-eastern Poland. It lies approximately north of Ostrów, north of Ropczyce, and north-west of the regional capital Rzeszów...
in Poland
Poland
Poland , officially the Republic of Poland , is a country in Central Europe bordered by Germany to the west; the Czech Republic and Slovakia to the south; Ukraine, Belarus and Lithuania to the east; and the Baltic Sea and Kaliningrad Oblast, a Russian exclave, to the north...
.
Armia Krajowa
The Armia Krajowa , or Home Army, was the dominant Polish resistance movement in World War II German-occupied Poland. It was formed in February 1942 from the Związek Walki Zbrojnej . Over the next two years, it absorbed most other Polish underground forces...
thanks to reports from local farmers. Armia Krajowa field agents even managed to obtain pieces of the fired rockets, by arriving on the scene before German patrols. In early March 1944, British Intelligence Headquarters
Secret Intelligence Service
The Secret Intelligence Service is responsible for supplying the British Government with foreign intelligence. Alongside the internal Security Service , the Government Communications Headquarters and the Defence Intelligence , it operates under the formal direction of the Joint Intelligence...
received a report of a Armia Krajowa
Armia Krajowa
The Armia Krajowa , or Home Army, was the dominant Polish resistance movement in World War II German-occupied Poland. It was formed in February 1942 from the Związek Walki Zbrojnej . Over the next two years, it absorbed most other Polish underground forces...
agent (code name: ‘Makary’) who had covertly surveyed the Blizna railway line
Rail tracks
The track on a railway or railroad, also known as the permanent way, is the structure consisting of the rails, fasteners, sleepers and ballast , plus the underlying subgrade...
and observed a freight car
Railroad car
A railroad car or railway vehicle , also known as a bogie in Indian English, is a vehicle on a rail transport system that is used for the carrying of cargo or passengers. Cars can be coupled together into a train and hauled by one or more locomotives...
heavily guarded by SS troops
Schutzstaffel
The Schutzstaffel |Sig runes]]) was a major paramilitary organization under Adolf Hitler and the Nazi Party. Built upon the Nazi ideology, the SS under Heinrich Himmler's command was responsible for many of the crimes against humanity during World War II...
containing ‘an object which, though covered by a tarpaulin, bore every resemblance to a monstrous torpedo’. Subsequently, a plan was formed to make an attempt to capture a whole unexploded V-2 rocket
V-2 rocket
The V-2 rocket , technical name Aggregat-4 , 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 combat-ballistic missile and first known...
and transport it to Britain. Around 20 May 1944, a relatively undamaged V-2 rocket fell on the swampy bank of the Bug River
Bug River
The Bug River is a left tributary of the Narew river flows from central Ukraine to the west, passing along the Ukraine-Polish and Polish-Belarusian border and into Poland, where it empties into the Narew river near Serock. The part between the lake and the Vistula River is sometimes referred to as...
near the village of Sarnaki and local Poles managed to hide it before German arrival. The rocket was then dismantled and smuggled across Poland. In late July 1944, the Polish resistance
Polish resistance movement in World War II
The Polish resistance movement in World War II, with the Home Army at its forefront, was the largest underground resistance in all of Nazi-occupied Europe, covering both German and Soviet zones of occupation. The Polish defence against the Nazi occupation was an important part of the European...
(Home Army and V1 and V2
Home Army and V1 and V2
Aside from the military operations, the Polish Armia Krajowa was also heavily involved in intelligence work, including work done with regard to the German "Wunderwaffe" - the V-1 flying bomb and the V-2 rocket...
) secretly transported parts of the rocket out of Poland in Operation Most III
Operation Most III
Operation Most III or Operation Wildhorn III was a World War II operation in which Poland's Armia Krajowa provided the Allies with crucial intelligence on the German V-2 rocket.-Background:...
(Bridge III), for analysis by British intelligence.
A4-SLBM
In Autumn 1943 Deutsche Arbeitsfront Director, Otto Lafferenz, proposed the idea of a towable watertight container which could hold an A4 rocket. This suggestion progressed to the design of a container of 500 tons displacement to be towed behind a U-boat. Once in firing position, the containers would be trimmed to bring them vertical for launch. The project was dubbed Projekt Schwimmweste and the containers themselves referred to by the codename Prufstand XII. Work on the containers was carried out by the Vulkanwerft, and a single example was completed by the end of the war, but never tested with a rocket launch.A4b/A9
In the event that launch sites might be forced back into the Reich itself, von Braun and his colleagues were put under pressure to develop a longer-range version of the A-4 known alternately as A-9 and A-4b, the reason for the dual designation being that the A-4 series had received "national priority"; the A-4b designation ensured the availability of scarce resources.In June 1939, Kurt Patt of the Peenemünde Design Office, proposed wings for converting rocket speed and altitude into aerodynamic lift and range. As the rocket encountered thicker atmosphere on its descent phase, it would execute a pullout and enter a shallow glide, trading speed for distance. Patt also proposed the Flossengeschoss (fin projectile). Both concepts were utilized by Walter Dornberger
Walter Dornberger
Major-General Dr Walter Robert Dornberger was a German Army artillery officer whose career spanned World Wars I and II. He was a leader of Germany's V-2 rocket program and other projects at the Peenemünde Army Research Center....
when he drafted a memo for presentation to Hitler regarding the "America rocket" on July 31, 1940.
Design studies on the A-9 began in 1940. In addition to its wings, the A-9 would have been somewhat larger than the A-4 and its engine would have produced about 30% more thrust. Following wind tunnel testing of models, the design was subsequently modified to replace the wings with fuselage strakes
Strake (aviation)
In aviation, a strake is an aerodynamic surface generally mounted on the fuselage of an aircraft to improve the airflow and hence the flight characteristics.In general a strake is longer than it is wide, in contrast to a winglet or a moustache....
, as the tests showed that these provided better lift at supersonic velocities and also solved the problem of transonic shift of the centre of lift.
Development was suspended in 1941, but in 1944 several V-2s were modified to an approximation of the A-9 configuration under the designation A-4b. It was calculated that by fitting wings, the A4's range would be extended to 750 km (466 mi), allowing targets in Britain to be attacked from launch sites within Germany itself. It was intended that following launch the curve of the A-4b's trajectory would become shallower and the rocket would glide toward its target. It was anticipated that interception by enemy aircraft at the end of the glide phase would be virtually impossible as over the target the A-4b was intended to enter a near vertical dive leaving little time for interception.
The A-4b concept was tested by fitting swept back wings to two A-4s launched from Blizna. However, little development work had been carried out and the first launch on 27 December 1944 was a complete failure. The second launch attempt, on 24 January 1945, was partially successful, in that the wing broke off, but the A-4b still managed to become the first winged guided missile to break the sound barrier and attain Mach 4.
A5
The A5 was a scaled-down test model of the A4 which replaced the former unsuccessful A3 in this role. It was flown from 1938 to 1942, and played a vital role in testing the aerodynamics and technology of the A4. It had the same rocket engine as the A3, but had a new control system plus its shape more closely resembled that of the A4. 25 were launched, some several times; it was fitted with a parachute recovery system, plus it could float for up to two hours before sinking, so allowing recovery by boat. Variants were constructed both with no propulsion system and monopropellantMonopropellant
Monopropellants are propellants composed of chemicals or mixtures of chemicals which can be stored in a single container with some degree of safety. While stable under defined storage conditions, they react very rapidly under certain other conditions to produce a large volume of energetic gases...
engines for air drop testing.
The A5 was 5.825 m (19.1 ft) long, with a diameter of 0.78 m (2.6 ft) and a takeoff weight of 900 kg (1,984.2 lb), and like the A3 was fueled with alcohol with liquid oxygen as an oxidant. The first launch of the A5 took place in the summer of 1938 at Greifswalder Oie
Greifswalder Oie
Greifswalder Oie is a small island in the Baltic Sea, located east of Rügen on the German coast. The island covers an area of about 54 hectares.-History:...
and the first successful guided flights were made in October 1939 in order to test the control systems planned for use in the A4. The A5 reached a ceiling of up to 12 km (7.5 mi).
A6
A6 was a designation applied to a variant of the A5 test rocket which used different propellants.Some sources indicate that it was also applied to a speculative proposal for a manned reconnaissance version of the A4b winged variant of the A4. This A6 was initially proposed to the German Air Ministry as an uninterceptable reconnaissance craft. It would be launched vertically by rocket, taking it to an apogee of 95 km (59 mi); after re-entering the atmosphere it would enter a supersonic glide phase, when its single ramjet would be ignited. It was hoped that this would provide 15 to 20 minutes of cruise at 2900 km/h (1,802 mph) and would allow the aircraft to return to its base and make a conventional runway landing assisted by a drag chute. However, the Air Ministry had no requirement for such an aircraft and the proposal was rejected. Similar concepts (though unmanned) were produced after the war in the form of the USA's SM-64 Navaho
SM-64 Navaho
The North American SM-64 Navaho was a supersonic intercontinental cruise missile project built by North American Aviation. The program ran from 1946 to 1958 when it was cancelled in favor of intercontinental ballistic missiles...
missile and the USSR's Burya
Burya
The Burya was a trisonic, intercontinental cruise missile developed by the Lavochkin design bureau , based on a request for proposal issued by the Soviet government in 1954. The purpose of the design competition was to develop a cruise missile capable of delivering a nuclear payload to the United...
, both intercontinental cruise missiles with ramjet propulsion.
A7
The A7 was a winged design that was never fully constructed. It was worked on between 1940 and 1943 at Peenemünde for the KriegsmarineKriegsmarine
The Kriegsmarine was the name of the German Navy during the Nazi regime . It superseded the Kaiserliche Marine of World War I and the post-war Reichsmarine. The Kriegsmarine was one of three official branches of the Wehrmacht, the unified armed forces of Nazi Germany.The Kriegsmarine grew rapidly...
. The A7 was similar in structure to the A5, but had larger tail unit fins (1.621 m²) in order to obtain greater range in gliding flight. Two unpowered models of the A7 were dropped from airplanes in order to test flight stability; no powered test was ever performed. The finished rocket should have produced a takeoff thrust of 15 kN and a takeoff weight of 1000 kg. The design had a diameter of 0.38 m and a length of 5.91 m.
A8
The A8 was a proposed "stretched" variant of the A4, to use storable propellants (most likely nitric acid & kerosene). The design never reached the prototype stage, but further design work was carried out after the war by a German rocket team in France as the "Super V-2". The project was eventually cancelled, but led to the French VeroniqueVéronique
Véronique is the designation of a French sounding rocket with liquid fuel drive that was developed partly by German scientists who worked in Peenemünde. The Véronique was built between 1950 and 1969 in several versions, of which the versions P2, P6 and R were only experimental models. They were...
and Diamant
Diamant
The Diamant rocket was the first exclusively French expendable launch system and at the same time the first satellite launcher not built by either the USA or USSR. As such it is the main predecessor of all subsequent European launcher projects...
rocket projects.
A9/A10
It was proposed to use an advanced version of the A9 to attack targets on the US mainland from launch sites in Europe, for which it would need to be launched atop a booster stage, the A10.Design work on the A10 began in 1940, for a projected first flight to take place in 1946. The initial design was carried out by Ludwig Roth und Graupe and was completed on 29 June 1940. Hermann Oberth worked on the design during 1941, and in December 1941 Walter Thiel proposed that the A10 use an engine composed of six bundled A4 engines, which it was thought would give a total thrust of 180 tonnes.
Work on the A10 was resumed in late 1944 under the Projekt Amerika codename, and the A10's design was amended to incorporate a cluster of 6 A4 combustion chambers feeding into a single expansion nozzle. This was later altered to a massive single chamber and single nozzle. Test stands were constructed at Peenemunde for firings of the 200 tonne thrust motor.
It was considered that existing guidance systems would not be accurate enough over a distance of 5,000 km, and it was decided to make the A9 piloted. The pilot was to be guided on his terminal glide towards the target by radio beacons on U-boats and by automatic weather stations landed in Greenland and Labrador.
The final design of the A10 booster was approximately 65 ft (19.8 m) in height. Powered by a 375000 lbf (1,668.1 kN) thrust rocket burning Diesel oil and nitric acid, during its 50 second burn it would have propelled its A9 second stage to a speed of about 2700 mph (1,207 m/s) and an altitude of 15 mi (24.1 km).
A11
The A11 (Japan Rakete) was a design concept which would have acted as the first stage of a three stage rocket, the other two stages being the A9 and A10.The A11 design was shown by von Braun to US officers in Garmisch-Partenkirchen; the drawing was later published in 1946 by the US Army. The A11 was shown as using six of the large single-chamber engines proposed for the A10 stage, with a modified A10 second stage nested within the A11. The design also showed the winged A9, indicating a gliding landing or bombing mission. To achieve orbit, either a new "kick stage" would have been required, or the A9 would have to have been lightened. In either case, only a payload of approximately 300 kg (661.4 lb) could have been placed in a Low Earth Orbit.
A12
The A12 design was a true orbital rocket. It was proposed as a four-stage vehicle, comprising A12, A11, A10 and A9 stages. Calculations suggested it could place as much as 10 tonnes payload in Low Earth Orbit.The A12 stage itself would have weighed around 3,500 tonnes fully fuelled, and would have stood 33 m (108.3 ft) high. It was to have been propelled by 50 A10 engines, fuelled by liquid oxygen and alcohol.
Further reading
- Encyclopedia Astronautica: A1, A2, A3, A5, A7, A8, A9, A10, A11, A9/A10/A11/A12
- V2 EMW A4b die bemannte Rakete
- http://www.aggregat-2.de/neubau.html - a site about the A2 (in German)
- The A4 Rocket (in German)
- Aerospace museum
- University of Oregon
- A8 statistics