The Lafferenz project was based upon an idea in the fall of 1943 by Deutsche Arbeitsfront Direktor, Otto Lafferenz which he had after witnessing the test launch of an A4 rocket. He proposed a submersible barge containing the ballistic missile be towed across the Atlantic by U-boat and then tilted upright to fire the rocket.
Little bio-graphical information survives about Otto Lafferenz and his fate after the war is unclear. Any further information would be welcomed. It is quite possible that he was either killed or captured by Soviet forces. Another possibility is that he may have been evacuated from Peenemunde along with Werner von Braun. In the latter case, it is possible he was given US citizenship and a new false identity to work on the US submarine ballistic missile program. Lafferenz supervised slave labour and therefore, if he survived the war, would have probably needed to conceal his Nazi activities. These remain just conjectures until firm bio-graphical details emerge.
This rocket was more commonly termed the V-2 missile. Peenemunde engineers termed the rocket type as Aggregate 4 which reflects how the lineage evolved with aggregated features from one missile to the next, gradually building performance.
The Lafferenz project has often been wrongly associated with a project called Pruffstand XII. The correct name appears to have been Projekt Schwimmweste (project swim vest) and also as Apparat F. From December 1944 Dr Dickmann led a team of engineers to create Lafferenz capsules.
The 105ft long (32 metre), 300 ton Capsule was intended to launch a 46 foot long, V-2 rocket at New York from within the 190 nautical mile range, which the missile could be fired. Plans later evolved to consider towing three 500 ton capsules. Tests were conducted with one Lafferenz capsule in the Baltic by U-1063 for Weapon Test Department 10. The whereabouts of this capsule after the war remains a mystery.
At least one uncompleted Lafferenz capsule was captured by Soviet forces at Stettin in the Eastern Baltic. Another capsule was completed in Schichau dockyards at Elbing, but could not be located after the war. A contract is known to have been let with Stettiner Vulcanwerft for construction of three such capsules.
U-873 was thought to have attempted a launch at New York, but to have aborted the mission in the last days of World War 2. She had originally been loaded with cargo in her keel for a mission to Japanese territory and then in March 1945, her mission was changed at short notice to attack New York. U-873’s captain Kapitanleutnant Freidrich Steinhoff had been deeply involved with submerged trials of the U-511, firing rockets off Penemunde and his brother Dr Ernst Steinhoff was a guidance systems engineer for the A4 rocket, in what was termed Projekt Rebstock.
Kapt Lt Steinhoff is known to have been brutally interrogated after the war in Portsmouth, New Hampshire, by a Naval intelligence team called Op-16-Z, later he was found dead in his cell in a pool of blood amidst claims of murder and a false entry of suicide on his death certificate.
Op-16-Z conducted similar horrific beatings on the officers and technicians of U-546.
If U-873 had indeed embarked upon such a mission, then it is likely it was abandoned at sea, well away from New York. US Naval intelligence certainly seemed convinced that Steinhoff had been on a Lafferenz type mission.
Rocket engineers at the Peenemunde test establishment referred to this rocket as the A4 in a series of rockets from A1 to A12. Hitler coined the term Vergeltungswaffe Zwei (revenge weapon 2), or more commonly simply the V-2 for public consumption. Today most people call the missile the V-2 rocket.
In practice storage of the liquid fuel of the V-2 created many problems in terms of time required to pre-pare for a launch. The sodium permanganate for example used to generate steam for the high speed fuel pumps, had to be preheated. Gyroscopes needed to be spun up. The rocket's own fuel tanks needed to be filled without spillage as this could lead to explosion if the chemicals mixed.
U-boats were most vulnerable when at the surface, due to Allied use of radar on aircraft and ships. This would have been especially so, close to New York late in the war. The Lafferenz capsules would have to remain sufaced for up to half an hour before firing.
The V-2 fuel comprised 8 tons of fuel, including liquid oxygen with ethyl alcohol and sodium permanganate for the turbo pump. Fuels would be stored in the barge's own tanks until before launch when there would be a transfer to the rocket's own tanks.
Another draw back was the high fuel consumption of the towing u-boat made the mission all but impossible except for a type IX-D2 class u-boat.
Plans have come to light after the war in private hands, which indicate the V-2 was intended to target lower Manhattan with a nuclear warhead. On Tuesday 2 April 1946, the New York Times published a map captured from Reichsmarschall Hermann Goering’s files, illustrating the aiming point for Vergeltungswaffe weapons at Delancey Street and the Bowery. This point was designated Zielpunkt.
On 10 December 1944, New York’s mayor Fiorello LaGuardia disclosed to the press he had knowledge of planned attacks. Then in January 1945, Germany’s Chief of War Production, Albert Speer boasted in Berlin radio broadcasts of planned Vergeltungswaffe attacks on New York. Late in the war Speer is known to have sabotaged Hitler’s Nero decree and it seems possible that Speer broadcast a prediction of the attacks to tip off the Allies. Speer was treated with considerable leniency after the war.
Principle sources:
Axis Submarine Successes, 1939-1945, by Jurgen Rohwer
Hitler’s Raketen U-Boote, The true story behind the development of the Ballistic Missile Submarine, (an as yet unpublished manuscript) by Paul M Lawton Esq