Editing Test Stand VII

{{Short description|Rocket testing site used by Nazi Germany during World War II}}
{{Use dmy dates|date=October 2014}}
{{Infobox Military Structure
| name             = Test Stand VII 
| nativename       = {{langx|de|Prüfstand VII}}
| partof           = [[Peenemünde|Army Research Center Peenemünde]],<br />[[Nazi Germany]]
| location         = [[Usedom]] island
| coordinates      = {{Wikidatacoord|Q2115519|type:landmark_region:DE-MV|display=inline,title}}
| image            = Peenemunde-165515.jpg
| image_size       = 300px
| caption          = 23 June 1943 RAF reconnaissance photo of Test Stand VII
| image2           = Pruefstand-VII-Peenemuende.jpg
| image2_size      = 300px
| caption2         = Diorama at Peenemünde Historical and Technical Information Centre
| type             = [[bunker]]
| code             = 
| built            = 1938<ref>{{cite web |last=Janberg |first=Nicolas |url=http://en.structurae.de/structures/data/index.cfm?ID=s0012008 |title=Montagehalle Prüfstrand VII |work=International Database and Gallery of Structures |publisher=Structurae |access-date=6 October 2008 }}</ref>
| builder          = [[Peenemünde#HVP Organization|HVP]]
| materials        = sand, concrete, brick, steel
| height           = {{cvt|10|m|ft}} hohe Bóschung<ref name=Klee/>
| used             = [[List of V-2 test launches|World War II]]
| demolished       = 1961<ref>{{cite web |url=http://skyscraperpage.com/cities/?buildingID=45850 | title=Prüfstand VII |work=Peenemünde |access-date=28 January 2008 |publisher=SkyscraperPage.com }}</ref>
| condition        = demolished
| ownership        = 
| open_to_public   = [http://commons.wikimedia.org/wiki/Historisch-technisches_Informationszentrum_Peenem%C3%BCnde Peenemünde Historical and Technical Information Centre]
| controlledby     = 
| past_commanders  = Engineers in Charge: Fritz Schwarz (1943),<ref name=Dornberger/>{{Rp|127,141}} Hartmut Kuechen (through May 1944), followed by [[Bipropellant rocket#References|Dieter Huzel]], then Dr. [[Kurt H. Debus]].<ref name=Huzel/>
|battles=[[Operation Crossbow]], [[Bombing of Peenemünde in World War II|Operation Hydra]]
|events=DERA rocket model club launches<ref>[http://www.dera.de/195.0.html Deutsche Experimental Raketen Arbeitsgruppe] {{webarchive |url=https://archive.today/20120731094333/http://www.dera.de/195.0.html |date=31 July 2012 }} {{in lang|de }}</ref>
| garrison         = 
| occupants        = 
}}
'''Test Stand VII''' ({{langx|de|Prüfstand VII}}, P-7) was the principal [[V-2 rocket]] testing facility at [[Peenemünde Airfield]] and was capable of static firing rocket motors with up to 200 tons of thrust. Notable events at the site include the [[List of V-2 test launches|first successful V-2 launch]] on 3 October 1942, visits by German military leaders, and Allied reconnaissance overflights and bombing.

==Description==
Two distinguishing features of P-7 were the 670-yard-long<ref name=Irving>{{cite book |last=Irving |first=David |author-link=David Irving |title=The Mare's Nest |year=1964 |publisher=William Kimber and Co |location=London |pages=20, 48–50, 56–58, 65 }}</ref> elliptical high-sloped sand wall and the wide concrete-lined trench (flame pit) with a large symmetrical water-cooled flame deflector of [[molybdenum]]-steel pipes. The concrete trench, nearly {{convert|25|ft|m}} wide with {{convert|3|ft|m}} concrete walls, sloped gradually away from each side of the flame deflector to a depth of {{convert|20|ft|m}}, rising again symmetrically toward the side of the arena. Beside the flame pit was a long underground room where {{convert|4|ft|m}} diameter delivery pipes were housed to route cooling water at 120 gallon per second from three huge pumps in the pumphouse to the flame deflector in the pit.<ref name=Dornberger>{{cite book |last=Dornberger |first=Walter |author-link=Walter Dornberger |title=V2—Der Schuss ins Weltall |orig-date=1952 |date=1954 |edition=translation: ''V-2'' Viking Press:New York |publisher=Bechtle Verlag |location=Esslingan |language=de |others=Cleugh, James and Halliday, Geoffrey trans. |isbn=0-553-12660-1 |pages=[https://archive.org/details/v2thebantamwarbo00walt/page/4 4,9–11,30,128–133,141] |url-access=registration |url=https://archive.org/details/v2thebantamwarbo00walt/page/4 }}</ref><ref name=Huzel>{{cite book |last=Huzel |first=Dieter K |title=Peenemünde to Canaveral |year=1962 |publisher=Prentice Hall |location=Englewood Cliffs NJ |pages=21,42–46,64–69,100,103,240 }}</ref>

While the elliptical sand wall was for blocking high sea winds and blown sand, concrete structures were integrated into the wall and under the ground to protect equipment and personnel from rocket explosions and enemy bombing (a sand-filled dummy warhead, called "the elephant", was normally used). A large gap in the wall allowed easy entry by vehicles (particularly railcars with propellants), and an open tunnel through the ellipse wall at the narrower southern end also allowed entry. Integrated into the ellipse wall next to the tunnel was a massive observation and measuring [[blockhouse]] containing the control center. The control center had a double door with a bulletproof glass window from which an observer maintained telephone communication with the Telemetering Building at a remote location from P-7. A receiver in a lighthouse near [[Koserow]] provided telemetry from rockets with the Wolman System<ref name=Neufeld>{{cite book |last=Neufeld |first=Michael J |title=The Rocket and the Reich: Peenemünde and the Coming of the Ballistic Missile Era |year=1995 |publisher=The Free Press |location=New York |isbn=0-02-922895-6 |page=[https://archive.org/details/isbn_9780029228951/page/103 103] |url-access=registration |url=https://archive.org/details/isbn_9780029228951/page/103}}
:{{note|2|Note 2}}: For automatic motor cutoff, in 1940-1941 Professor Wolman of Dresden created an alternative of his tracking system to use a ground signal transponded by the A-4 to measure the velocity of the missile and, by triangulating from multiple sites, determined the trajectory.</ref> for [[Doppler radar|Doppler]] tracking.<ref name=Pocock>{{cite book |last=Pocock |first=Rowland F |title=German Guided Missiles of the Second World War |year=1967 |publisher=Arco Publishing Company, Inc. |location=New York |page=18 }}</ref> For rockets that used radio control for V-2 engine cutoff, the [[Brennschluss]] equipment included a transmitter on the bank of the [[Peene]] about {{convert|7.5|mi|km}} from P-7 and the [[Doppler radar]] at [[Lubmin]] (a motorized [[Würzburg radar]], the "rhinoceros").<ref name=Dornberger/><ref name=Huzel/>

===Control room===
The control room also had switchboards, a row of four [[periscope]]s, [[manometer]]s, frequency gauges, [[voltmeter]]s and [[ammeter]]s, green/red/white signal lamps, and switches at the propulsion console and guidance panel to dynamically display approximately 15 measurement points within the rocket. Additionally, the control room had a big "X-time" [[countdown]] clock that displayed the time until launch, which was announced via loudspeakers as "''X minus four minutes''", etc. In addition to the control room, the blockhouse also contained offices, a conference room, a small dormitory with double bunks and an adjoining shower, a wash room, and a workshop. A long underground corridor led from the measurement blockhouse to a room in the concrete foundation by the flame pit, and multiple rows of measurement cables covered the walls of the tunnel. A different gradually rising tunnel led from the long flame pit room to the exterior of the arena near the pumphouse ({{langx|de|Pumpenhaus}}). Near the pumphouse were high wooden towers to cool the water, and {{convert|25|ft|m}} high tanks for the recooling water were integrated into the ellipse wall.<ref name=Dornberger/><ref name=Huzel/>

===Test tower===
The prominent tower within the arena was a mobile test frame/crane (''Fahrbare Kranbühne'')<ref name=Klee/> which could be moved over the flame pit to position the rocket nozzle 25 feet above the deflector, and which allowed an entire missile to be gimbaled in two directions up to five degrees from vertical. The tower included an elevator and a German-made [[Mettler Toledo|Toledo scale]] for thrust measurements. Actual launches were from a steel table-like structure (firing stand, ''Brennstand'') across the railway from the flame pit on the test stand's large concrete foundation. Under the concrete foundation were the recorder room, a small shop, an office, compressed nitrogen storage cylinders, and catch tanks. The arena also included an engine cold-calibration pad for conducting flow test measurements by pumping water (instead of [[Liquid oxygen]]) and [[List of Stoffs|alcohol]] (which was recovered afterward) via the turbopump through the combustion chamber. Since the V-2 motor had no controller for the turbopump, cold-calibration allowed the determination of "freak cases" of equipment.<ref name=Dornberger/><ref name=Huzel/>
{{Quote box |width=25em |align=left |bgcolor=#B0C4DE
|title=Launch Failure Description
|quote=The heavy missile ... rose only 15 feet above the firing table. Then it stood still! It stood upright in the air, showing no desire to turn over or to revolve about its longitudinal axis. It was an unbelievable sight. At any moment the rocket would topple or fall back, crash and explode. ... But I still kept my binoculars on the rocket. ... There must have been an interruption in the output of the steam generator for the propellant-pump turbine. ... The film operator, Kühn, had taken up position facing me on the [elliptical] wall of the test stand. He must have had good nerves. The rocket hung in the air just 100 yards away.[from Kühn] Nothing daunted, ... He certainly knew from experience that the moment the projectile fell back he would be in mortal danger. He just went on cranking. ... Our exhaust vanes were doing a wonderful job. The rocket stood unsupported in the air, as straight as a ramrod. Only 4 seconds had passed, ... The rocket was bound to topple now. The tilt [for trajectory control] would now begin automatically. ... The rocket grew lighter owing to the steady fuel consumption. Almost imperceptibly, yard by yard, it began to climb. Its nose turned very gradually eastward. ... At a height of 30 to 40 feet it moved slowly, still practically upright, toward the cameraman. He went on cranking. I caught my breath. Just a little more tilt and the rocket would certainly capsize and explode ... Now it was over the wall. Kühn knelt down and pointed his camera almost straight upward. It was going to be some film! ... I knew what was bound to come. ... I saw him get up slowly, still cranking. His camera was now practically horizontal. Then he pointed it diagonally down from the high wall. Boom! ... Smoke, flames, fragments of sheet-metal, branches, and sand whirled through the air. The rocket had crashed ... 40 yards beyond the wall ... The cameraman was still cranking. ... I was filled with an immense pride. ... only with men like this, could we finish the job that lay before us.
|salign=left
|source=[[Walter Dornberger]], {{circa|1943}}
}}

===Hangar===
[[File:Peenemunde test stand VII.jpg|thumb|12 June 1943 RAF reconnaissance photo of Test Stand VII]]
Outside of the arena was the 150x185x100h foot<ref name=Klee>{{cite book |last=Klee |first=Ernst |author2=Merk, Otto |title=The Birth of the Missile:The Secrets of Peenemünde |date=1963 |edition=English translation 1965 |publisher=Gerhard Stalling Verlag |location=Hamburg |page=29 }}</ref> assembly and preparation hall/[[hangar]] ({{langx|de|Montagehalle}}), which had been designed to be able to handle a larger [[Aggregate series|A9/A10]] [[multi-stage rocket]] that was planned, but never built. The roof of the hangar had camera stations for filming events.

==Allied reconnaissance and bombing==
On 15 May 1942 after photographing German destroyers berthed at the port of [[Kiel#History|Kiel]], [[Supermarine Spitfire|Spitfire]] pilot Flight Lieutenant D. W. Stevenson photographed 'heavy construction work' near the Peenemünde aerodrome. Later in the month [[Constance Babington Smith]] decided ''the scale was too small ... then something unusual caught my eye ... some extraordinary circular embankments ... I then dismissed the whole thing from my mind.''<ref name=Irving/><ref name=Ordway>{{cite book |last=Ordway |first=Frederick I III |author2=Sharpe, Mitchell R |title=The Rocket Team |series=Apogee Books Space Series 36 |year=1979 |publisher=Thomas Y. Crowell |location=New York |pages=98,114,295 }}</ref> Then a year later on 22 April 1943, Bill White and Ron Prescott in RAF [[de Havilland Mosquito]] DZ473 were sent from [[RAF Leuchars|Leuchars]] to photograph damage from Allied bombing at the [[History of Szczecin#In the Third Reich (1933-1945)|Stettin]] railyards: "On leaving Stettin, we left our cameras running all down the north coast of Germany, and when the film was developed, it was found to contain pictures of Peenemünde." The [[RAF Medmenham|Medmenham]] interpreters studied the elliptical earthworks (originally photographed in May 1942) and noticed an "object" {{convert|25|ft|m}} long projecting from what was thought to be a service building, although it had mysteriously disappeared on the next frame.<ref name=Bowman>{{cite book |last=Bowman |first=Martin W. |year=1999 |title=Mosquito Photo-Reconnaissance Units of World War 2 |url=https://books.google.com/books?id=Gx85T-eYPdQC&pg=PA19 |publisher=Osprey Publishing, Limited |isbn=978-1-85532-891-4 |access-date=6 October 2008 |page=16 }}</ref>

On 22 April 1943 a large cloud of steam was photographed near the embankments, which was later identified as coming from a rocket engine being test fired.<ref name=Jones/>{{Rp|433}} [[Duncan Sandys]]' first photographic reconnaissance report on Peenemünde was circulated on 29 April 1943, which identified that the lack of power-station activity (Germany had installed electrostatic dust and smoke removers on the power station near [[Stavenhagen#Subdivisions|Kölpin]]) indicates that "''The circular and elliptical constructions are probably for the testing of explosives and projectiles. ... In view of the above, it is clear that a heavy long-range rocket is not an immediate threat.''" Then on 14 May, an "''unusually high level of activity''" was visible at "the Ellipse" on photos from two sorties on 14 May, which was the date the Reich Director of Manpower (Gauleiter [[Fritz Sauckel]]) was a distinguished visitor at a launch.<ref name=Irving/>
The first solid evidence of the existence of a rocket came with a sortie (N/853) on 12 June, when a [[Supermarine Spitfire operational history|Spitfire]] flown by Sqn Ldr Gordon Hughes photographed Peenemünde: one photograph included an object on a railway truck. [[Reginald Victor Jones]] identified the object on 18 June as "''a whitish cylinder about 35 feet long and 5 or so feet in diameter with a bluntish nose and fins at the other end...I had found the rocket.''"<ref name="Jones">
{{cite book |last=Jones |first=R.V |author-link=Reginald Victor Jones |title=Most Secret War:British Scientific Intelligence 1939-1945 |publisher=Coronet Books (Hodder and Stoughton) |year=1979 |location=London UK |pages=433–435}}<br />

: {{note|2|Note 2}}: On 13 June, Dr Jones sent a note to Sandys and "''two or three days later an addendum was '''added the report by from''' Sandys' interpreter, saying that '''an object''' was visible on the photograph without any mention that anyone but himself had found it. This experience certainly confirmed my impression that my help was being avoided.''"{{Rp|435}}</ref>{{Rp|434}}<ref>{{Cite book |last=Cabell |first=Craig |url=https://www.google.com/books/edition/Operation_Big_Ben/pXNfDgAAQBAJ?hl=en&gbpv=1&dq=Reginald+Victor+Jones+v2+rocket&pg=PT45&printsec=frontcover |title=Operation Big Ben: The Anti-V2 Spitfire Missions |date=2017-03-17 |publisher=Fonthill Media |language=en}}</ref><ref>{{Cite book |last=Longmate |first=Norman |url=https://www.google.com/books/edition/Hitler_s_Rockets/KJUjBbIhSLIC?hl=en&gbpv=1&dq=%22cylinder+about+35+feet+long+and+5+or+so+feet+in+diameter%22&pg=PA70&printsec=frontcover |title=Hitler's Rockets: The Story of the V-2s |date=2009-07-23 |publisher=Skyhorse Publishing Inc. |isbn=978-1-60239-705-7 |language=en}}</ref>
After [[Operation Hydra (1943)|Operation Hydra]] bombed other areas of [[Peenemünde]] in 1943, the P-7 blockhouse roof was reinforced, and in a [[Bombing of Peenemünde in World War II#1944 Bombings|1944 raid]], the blockhouse occupants suffered one injury when a periscope fell.<ref name=Huzel/>{{Rp|105,115}} (Hermann Weidner's Test Stand 8 was lost in the 1944 July and August raids).<ref name=Ordway/>{{Rp|98}}

The last V-2 launch at Peenemünde was in February 1945, and on 5 May 1945, the [[2nd Belorussian Front]] under General [[Konstantin Rokossovsky]] captured the port of [[Świnoujście|Swinemünde]] and the [[Usedom]] island. Russian infantry under Major Anatole Vavilov stormed Peenemünde and found it "75 per cent wreckage" (the research buildings and test stands had been demolished.)<ref name=Ley>

{{cite book |last=Ley |first=Willy |author-link=Willy Ley |title=Rockets, Missiles and Space Travel |url=https://archive.org/details/rocketsmissiless0000leyw |url-access=registration |orig-date=1944 |year=1951 |edition=revised edition 1958 |publisher=The Viking Press |location=New York |page=[https://archive.org/details/rocketsmissiless0000leyw/page/243 243] }}</ref> A former adjutant at Peenemünde, Oberstleutnant Richard Rumschöttel, and his wife were killed during the attack,<ref name=Ordway/> and Vavilov had orders to destroy the facility.<ref name=Ley/>
{{external media|float=right |width=100px
|image1=[https://books.google.com/books?id=Gx85T-eYPdQC&pg=PA19&sig=U121jgQ9ZHqXpIbCc0tMUhygrUE Bombing damage]
}}

{{-}}

==References==
{{Reflist}}

==External links==
{{commonscat-inline|Prüfstand VII|Test Stand VII}}
{{V-weapons}}
{{WWII Operation Crossbow}}

{{DEFAULTSORT:Test Stand Vii}}
[[Category:Peenemünde Army Research Center and Airfield]]
[[Category:German V-2 rocket facilities]]
[[Category:Rocket launch sites in Germany]]
[[Category:V-weapon subterranea]]
[[Category:World War II sites in Germany]]
[[Category:World War II sites of Nazi Germany]]
[[Category:Military installations established in 1938]]
[[Category:Buildings and structures demolished in 1961]]
[[Category:Demolished buildings and structures in Germany]]
[[Category:Ruins in Germany]]
[[Category:1938 establishments in Germany]]
[[Category:V-2 missile launch sites]]
[[Category:1961 disestablishments in East Germany]]