Can a pile of scrap unmask a new high technology? The A4/V-2 No V89 Bäckebo-torpeden

Three months before the first V-2 rocket attack on London a test vehicle crashed in southern Sweden on June 13, 1944. At this time the Allied only had limited knowledge about the rocket (A4/V-2) from agent reports and information from the Polish resistance investigating some remains from a crashed test vehicle in Poland. London was confronted with a new weapon supposedly able to carry an explosive warhead of several tons some 250 km.The A4/V-2 rocket test vehicle number V89 broke apart shortly before impacting ground. In a short time 2 t of metal parts and electrical equipment was collected and transported to Stockholm for investigations. A first Swedish report was ready by July 21, 1944 and the rocket parts were then transported to England for further investigations. By August 18, 1944 the Royal Aircraft Establishment (RAE) had its preliminary report ready. But how close to reality can a complex vehicle be reconstructed and the performance calculated from a pile of scrap by investigators dealing with a technology not seen before?In the early 1940s the state of art of liquid propellant rocket technology outside Germany was limited and the size of a liquid rocket engine for the likely performance hardly imaginable. The Swedish and British reports, at that time classified as top secret, have since been released and permit a very detailed analysis of the task to reconstruct the rocket vehicle, the engine itself and its performance. An assessment of the occurrence at Peenemünde and how the rocket became astray and fell in southern Sweden, together with the analyses by Swedish and British military investigators give a unique insight into the true nature of the V89. It shows the real capabilities of early aeronautical accident investigation methods in combination with solid engineering knowledge to unmask a new high technology.