Interrogation of Helmut Grottrup*
* As usually in these kinds of reports, correct spelling is not very much prevented, as the title originally mentioned Gottrup!
Reported By:
W. Hausz, U.S. Ord.
28 May 1945
CIOS Target Number 4/95
Rockets & Rocket Fuels
Subject
Work at Manfred von Ardenne
Organization of Group 22 (Steinhoff)
Telemetering
Kommando Systems
The A Series of Missiles and their Control
Dipl.-Ing. Helmut Grottrup graduated from Technische Hochschule Berlin in 1939, was employed by Manfred von Ardenne (private laboratory) for six months then went to Peenemünde in December 1939. Rose from making laboratory measurements to assistant to Kirchstein, then, in December 1943 to assistant of Steinhoff who was in charge of all electrical work under von Braun. His position there was head of the Technischestelle (or Technical Point) a small committee of about five through which the various selections made contact with Steinhoff. He has broad general knowledge of all the sections under Steinhoff. He can not give detailed circuits of any project except those he worked on before 1943. He is married, has two children aged 4 years and 6 months. Both he and his wife speak English. Both allegdly have strong demoncratic leanings and were under close arrest for over a year although he continued work. There was allededly an order for his hanging in Nordhausen just before he left with the train for Munich. He got off the train before Munich, hid, then made his way back to Nordhausen after occupation.
Work at manfred von Ardenne .....
Organization of Group 22 (Steinhoff) .. Directly under Steinhoff was the Technischestelle of about 5 persons which functioned as a clearing house for technical matters. Grottrup headed this. Then there were nine sections, 221-9
221 - Prof. Wierer and 50 persons: Bordnetz and Bodennetz ..
222 - Dr. Hoelzer* and 90 persons: Azimuth control and stability control (of A1-A9 series), gyros, Mischgerät, servos sequence switches ....
Prof. Kirschstein and 80 persons: Brennschluss control and telemetering ... Wolmann Verdoppler ..
Dr. Netzer and 120 people: Control of Wasserfall (C-2). In this section was dr. Slevogt who worked on homing devices .. directly reported to von Braun.
Dr. Brutzil and 300 men: This section consisted of a few engineers, but mostly draftmen ...
Bohm (Böhm?, AOB) and 70 men: Headed what was called the Konstructionsburo (Construction Bureau for Steinhoff ..
Debus and 50 men: In charge of all electrical electrical apparatus .... He was evacuated in February from P. to a place north of Rehden which was near to Bremen. ....
Dr. Gengelbach and 100 men: First models of all ground apparatus. Of some equipment such as Wolmann Brennschluss ...
Neubert and 30 men: (a) Led production of test machines for A-4 (= V2, AOB) (component part test) (b) Liaison with Sonderauschuss (the production coordinator of all directed missiles) namely Direktor Kunzer (c) In charge of diverting from production ...
Telemetering
Messina was the code name for all telemetering apparatus .. (section 223) ...Prof Busch of TH Darmstadt ..
Messina I consisted of a carrier with up to ten ....
Messina Ib and Ic ...
Messina Ib was sponsored by Prof. Fassbender ...
.... The block diagram of Messina Ic is shown in Fig. 1 ...
Messina II was very complicated by comparison. An oszillator fed a phase spliter which put out 12 signals ..FÜ/7 - Palermo-Honnef System - Potsdam-Berlon System .....
All of these telemetering systems were expected to have about the same accuracy - nemely 2%.
Kommando systems ..............
receiver Potsdam - Berlon system ............
The A Series if Missiles and their Control ... A-1 to A4 (Old missiles now discarded .. A-4 The V2 .. A-5 A Missile half the size of V-2 that used for development of control ....
A-6 Same size as V-2, but was to use Solbei (nitric acid) instead of liquid oxygen
A-7 Similar to A-5, but ...
A-8 Same size as V-2, and same oxidant (LOX) but with little wings ...
A-9 Same size as V-2, oxidant was Solbei and was to have little wings ..
A-10 A very large missile for trans-Atlantic shots ..
In addition there was a project known as A-4b ...
Brennschlss control ... Iller gyroscopic type ..
Wolmann's apparatus measured the missile velocity ..
Prof. Wolmann had been supervising a series of 200 shots at Tüchelerheide to find ...
Freya - Erstling Line Control ..
Line control .. A lateral accelerometer ..
Proposed trajectory of A-9 and A-46 (most like should be V-4b< AOB)
Antenna Types Used on A-4 ......
Leitstrahl is ...
* Again it chould be: Dipl.-Ing. Hoelzer, as he took his Ph.D. in 1946 at Darmstadt
Back to, or proceed with: CIOS index page
Back to, or proceed with: FIAT-CIOS-BIOS main index page