by Gregory P. Kennedy

The V-2 was the world’s first large ballistic missile.  Fielded by Germany in the last eight months of World War II, thousands were launched against Allied targets.  Known simply as the Aggregate 4 (Assembly 4) to its creators, the Nazi Propaganda Ministry dubbed it the Vergeltungswaffe 2 (Vengeance Weapon 2) or V-2 for short.  The V-2 accompanied the V-1 cruise missile, which the Germans deployed in June 1944.  Both carried one-ton high explosive warheads, but the V-1 flew in a straight line at a constant altitude.  Although it flew at a relatively fast speed for its time – 360 miles per hour – it could be intercepted and shot down by antiaircraft guns or fighter aircraft.  The V-2, by comparison, struck at supersonic speeds with no advance warning, which made countermeasures impossible.

Development of the V-2 began in 1933 when (then) Captain Walter Dornberger hired Wernher von Braun to develop rockets for the Wehrmacht.  The Treaty of Versailles, which ended World War I, imposed strict limitations on Germany’s military.  Since Germany had been the aggressor in the “war to end all wars,” the victorious Allies tried to ensure that the Germans only had a defensive capability.  Such weapons as airplanes and airships were banned, and the size of field artillery pieces was strictly limited, as was the overall size of the German army.  One thing the Treaty failed to mention was rockets, so Dornberger’s superiors in the Army Ordnance Department felt this was a legitimate avenue to pursue.

Despite the fact that the Ordnance Department felt they could legitimately pursue rocket development, the program was carried out in great secrecy.  At first, von Braun conducted his experiments at the Army proving ground at Kummersdorf, which was just outside Berlin.  He achieved his first success just before Christmas 1934 with a pair of rockets he dubbed the Aggregate 2 (A-2).  The earlier A-1 exploded during a test.  Rather than rebuild the shattered A-1, he decided to move on to the improved A-2.  The A-2s were about five and a half feet tall, one foot in diameter, and weighed 400 pounds.  The pair of rockets, which were given the nicknames Max and Moritz, reached an altitude of one and a half miles.  Even these modest size rockets were too large to launch at Kummersdorf; von Braun conducted the flights from the Baltic island of Borkum.

Encouraged by the successful A-2, von Braun started work on the much larger A-3.  The A-3 was 21 feet tall, weighed 1,650 pounds at launch, and had a motor that produced a thrust of 3,300 pounds.  It also had a three-axis gyroscopic control system to keep it on course.  The Army rocket group virtually took over another small island in the Baltic named Greifswalder Oie for the A-3 flights.

In the midst of work on the A-3, Dornberger set down the parameters for the next rocket, the A-4, which was supposed to be the final weapon version.  For starters, he wanted it to have a range of 160 miles, which was double that of the Paris Gun of World War I.  He also wanted it to deliver a one-ton warhead.  Finally, the missile had to be compact enough to travel through railroad tunnels and the roads in small villages.  These criteria established the overall size of the A-4.

Everyone eagerly anticipated launching the first A-3 in December 1937.  While the A-2 relied on a heavy gyroscopic rotor between the fuel tanks for stability, the A-3 had a gyroscopic guidance system.  Gyroscopes in the nose of the rocket detected unwanted movements and sent corrective signals to vanes mounted in the engine exhaust.

Visiting dignitaries watched launch preparations from a boat.  Finally the moment came, the rocket motor roared to life, and the rocket lifted off.  It failed.  The A-3 flew successfully for about five seconds then nosed over.  The parachute ejected and the rocket tumbled into the sea.  Thinking the parachute had caused the problem, it was removed from the second rocket.  The results were the same.  Two successive A-3s also failed.  The problem was in the guidance system.  Although Germany’s top gyroscope expert designed the system, it was inadequate for stabilizing a rocket.

What followed was more than four years of development work on the A-4.  To test ideas for the large missile, the engineers used a smaller test bed, designated the A-5.  By this time, the rocket program had moved to another Baltic island, Penemünde.  The Luftwaffe showed interest in rocketry early on and provided five million RM to construct a rocket development laboratory.  The Army responded by providing six million.  While visiting his parents at Christmas, 1935, von Braun mentioned his need for an isolated site for a research center.  His mother mentioned the island of Usedom where his father used to hunt ducks.

Usedom was within sight of the Greifswalder Oie.  The Peene River flows along the western side of the island and empties into the Baltic Sea.  There was a small fishing village named Peenemünde near the river’s estuary.  The Wehrmacht purchased the island from the City of Wolgast, which owned it, and construction began on a new top-secret rocket laboratory that was shared by the German Army and Air Force.  Peenemünde East was the Army installation; the Luftwaffe area was designated Peenemünde West.  The Air Force managed the construction, so the buildings had a modern, contemporary look rather than the traditional, 19th Century style architecture favored by the Army.

Despite the infusion of money and new facilities, the A-4 had to struggle for resources, especially after World War II began on September 1, 1939.  Key civilian personnel were being drafted, and the entire project was in danger of collapse.  An interesting subterfuge was created to retain personnel.  The Army created a new unit, the Versuchskommando Nord (Experimental Command North), that was designated as a combat unit assigned to the home front at Peenemünde.

On October 3, 1942, an A-4 stood on the launch pad at Test Stand VII, ready for launch.  This was the fourth missile crafted in the shops at Peenemünde.  Missile #1 was used for ground handling tests and training; the next two rockets failed shortly after launch.  Everyone associated with the flight knew another failure could very well end the program.  Finally, the countdown reached zero, the engine roared to life, and the A-4 took off.  The missile continued to climb until it was out of sight.  Fifty eight seconds after liftoff, the engine finally shut off.  The rocket continued to coast along a ballistic arc until it impacted the Baltic 118 miles from Test Stand VII.  Dornberger had the success he needed.

Two more years of testing were needed before the A-4 could finally be fielded.  During field trials in Poland, it was discovered that many rockets exploded in the air before hitting their target.  This problem was finally solved by adding insulation between the tanks and body shell and by strengthening the structure near the nose.  By the time the A-4 entered combat, there had been more than 60,000 design changes introduced since the first successful flight.

Not wanting to relinquish its claim on long-range strategic bombing, the Luftwaffe developed a cruise missile, the Fiesler (Fi) – 103.  In the spring of 1943, a trial was held to determine which weapon, the Fi-103 or A-4, should enter production.  Despite the fact that both Fi-103s malfunctioned and both A-4s performed well, it was decided to go ahead and field both weapons.  Each had its own characteristics that complemented each other.  Although it could be intercepted, the Fi-103, which became the V-1, was relatively inexpensive to produce so large numbers could be launched.  It did require fixed launching ramps that could be bombed, so they had to be carefully camouflaged.  By comparison, the A-4 was immune from countermeasures and was launched by mobile field batteries, but it was far expensive to produce and required exotic propellants.

The first successful flight attracted the attention of Heinrich Himmler, head of the SS.  He managed to wrest control of the missile from the Army.  Production missiles were built by slave labor in an underground factory near Nordhausen.  Conditions were particularly brutal and an estimated 20,000 workers died, mostly from disease or exhaustion.  The concentration camp was named “Dora,” and was described as “the hell of concentration camps.”

The A-4 comprised five major segments:  the warhead; control compartment; midsection; tail section; and propulsion unit.  The warhead contained Amatol, a high explosive.  All missiles were assumed to follow the same initial trajectory, so range became a function of velocity at engine cutoff.  Accelerometers contained in the control compartment determined the missile velocity and signaled engine cutoff.  The control compartment also housed the timers that triggered various operations of the rocket.  The A-4 burned liquid oxygen and alcohol.  Each propellant had an aluminum tank supported in a steel body shell to comprise the midsection.  Four fins were bolted to the tail section.  For steering, the A-4 had carbon vanes in the engine exhaust and air vanes on the tips of each fin.  At the heart of the rocket was the propulsion system, which produced a thrust of 56,000 pounds.  A turbopump powered by the decomposition of concentrated hydrogen peroxide forced propellants into the combustion chamber.

The first combat launch took place on September 6, 1944.  The A-4 had become the V-2.  Paris was the target of the first two missiles – both failed.  Two days later German crews fired another V-2 towards Paris and two missiles against London.  By the time the last V-2 was launched in March, 1945, thousands had been fired against allied targets.  London and Antwerp, Belgium, were particularly hard hit and the missiles caused more than 6,000 deaths and wounded another 30,000 people.  Despite the misery it caused, the V-2 did not affect the outcome of the war.  Hitler had hoped the missile, by striking without warning, would terrorize the Allies into capitulation.  However, the estimated 1,115 rockets that hit England could not compete with the thousands of bombers that flew over Germany every day.

At the end of the third Reich collapse, there was a dash across Europe to recover V-2 missiles and components.  The Soviets captured Peenemünde but found von Braun and his key personnel had fled west with their technical archives to surrender to the Americans.  The US Army captured the underground factory near Nordhausen.  The area was scheduled to be turned over to the Soviets, so the Americans began an all out effort to remove as much missile hardware as possible.  They shipped the recovered hardware to the newly established White Sands Proving Ground in New Mexico.  The British rounded up enough hardware to assemble eight missiles, three of which were launched from Cuxhaven into the North Sea in a program called “Operation Backfire.”

Once the Soviets took over the underground factory, they mounted an effort to restart the production line.  Eventually, they succeeded and moved the operation back to the Soviet Union where they produced copies of the V-2, which they dubbed the R-1.  Sergei Korolev, who became the “Chief Designer” of the Soviet space program, headed the R-1 program.  He modified and improved the V-2 before embarking on his own designs in the 1950s.

The Americans shipped an estimated 300 railroad cars full of missile components to the New Mexico desert.  Recognizing the importance of long range rockets in any future conflict, the United States Army established the White Sands Proving Ground, an overland range measuring 40 by 100 miles, where V-2s could be launched.  The American effort to reassemble and launch V-2s was known as Project Hermes.  General Electric had the Hermes contract.

For stability, the V-2 had to carry a ton in its nose.  Since the Army had no need for launching explosive warheads, officials offered scientists the chance to place instruments aboard the missiles.  Hermes V-2s carried a variety of payloads that included solar spectrographs, cosmic ray counters, and the first biological payloads launched into space.  One rocket even carried M-7 rifle grenades that were fired in an attempt to create artificial meteors.

At the end of World War II, the largest American rocket was the 16-foot tall WAC Corporal.  In 1947, the Army began Project Bumper, which used the V-2 as a first stage for the WAC Corporal.  Bumper was the first two-stage liquid fuel rocket.  General Electric had overall responsibility for Bumper.  The Jet Propulsion Laboratory of the California Institute of Technology, which developed the WAC, performed the performance calculations and designed the separation system.  Douglas Aircraft built the WAC and necessary hardware for the two-stage system. 

There were eight Bumper vehicles, six of which were launched at White Sands.  Bumper #1 took off on May 13, 1948.  As a test mission, the second stage only contained a small solid fuel rocket to test the separation system.  Bumper #2, launched three months later, was the same.  On September 30, 1948, the third missile was launched. The second stage used a liquid propellant with 32 seconds burning time. Operation of the V-2 was successful in all aspects; however, the second stage motor exploded just prior to separation.  Bumper 4 appeared normal at first then an alcohol pipe in the V-2 broke.  The rocket went out of control and crashed.

Bumper 5, launched on February 24, 1949, was the first Bumper to be fired with a fully tanked second stage which allowed 45 seconds burning time.  The WAC Corporal, with its power added to that of the V-2, attained a speed of 5,150 miles per hour and an altitude of approximately 250 miles. This was the greatest velocity and the highest altitude ever reached by a man-made object.  The sixth Bumper also had a fully tanked second stage, and it was hoped that the performance of Bumper 5 could be surpassed.  The V-2 engine shut down early and the WAC did not separate.

The last two Bumpers were launched from the newly created Joint Long-Range Proving Ground at Cape Canaveral, Florida.  The first attempt to launch Bumper 7 was unsuccessful due to moisture collected within the missile. It was necessary to return it to the hangar where it was dried and rechecked.  Bumper 8 was erected on the pad and launched on July 24, 1950.  This was the first rocket launched from Cape Canaveral.  Bumper 7 was successfully fired on July 29, 1950.  These flights were not made for altitude; rather, they followed relatively shallow trajectories to achieve speeds of Mach 9 (nine times the speed of sound.)

The US Army’s First Guided Missile Battalion launched the last four V-2s from White Sands.  TF-1, launched on August 22, 1951, was allowed to consume all its propellants to see how high a flight could be achieved.  It reached 132 miles, the highest altitude attained by a V-2.  The last flight, TF-5 (TF-3 was never launched) blasted off on September 19, 1952.

In all, more than 70 V-2s were assembled and launched in America.  These flights provided the first practical experience with large liquid fuel rockets in the United States and formed the basis for later American advances.  Wernher von Braun and his team went to work for the US Army and developed the Redstone and Jupiter missiles.  When NASA came into being in 1958, this group formed the nucleus of the Marshall Space Flight Center in Huntsville, Alabama, where the Saturn V that took us to the moon was developed.