Pretty memo on the Horten brothers (1947)

Pretty memo on the Horten brothers (1947)

Date	16 December 1947
Title	"Horton Brothers (Flying Saucers)" [sic]
From	Lt. Col. Harry H. Pretty, S-2 Branch, Headquarters Berlin Command, Office of Military Government for Germany (US)
To	Deputy Director of Intelligence, European Command, Frankfurt; copy to Director of Intelligence, OMGUS
Classification	SECRET
Finding	No flying saucer design "ever existed nor was projected by any of the German air research institutions"
Testimony	Shellenberger testimony, p. 39
People	Horten brothers, Harry H. Pretty
Year	1947 in UFO history
Timeline	1947 on the UAP Timeline
Sources	7

The Pretty memo is a secret U.S. Army intelligence memorandum of 16 December 1947, titled "Horton Brothers (Flying Saucers)". It reports an inquiry in occupied Germany into the aircraft designers Reimar and Walter Horten, and into whether any German "flying saucer" design had existed. Everyone questioned said that, to their knowledge, no such design "ever existed nor was projected by any of the German air research institutions".^[1] The memo was published by the research group Project 1947. The anonymous UAP timeline in Michael Shellenberger's 2024 congressional testimony notes that the finding was never presented to Congress in open session.^[7]

Background

• After the 1947 wave of sightings, investigators considered whether German aircraft designs, perhaps in Soviet hands, could explain the flying discs. Project Sign, the Air Force's first UFO study, noted that the Hortens' flying-wing designs resembled some reports.^[2]
• The Horten brothers built a series of tailless flying-wing aircraft. Their best known, the jet-powered Horten H.IX (RLM designation Ho 229), was ordered into production at Gothaer Waggonfabrik but never completed. The nearly finished V3 prototype was taken to the United States and is now at the Smithsonian's National Air and Space Museum.^[3]
• The journalist Annie Jacobsen later described a wider 1947–48 Army Counter Intelligence Corps hunt for the brothers, which she called "Operation Harass", drawing on more than 300 pages of documents released in 1994. Her account says the brothers were located in March 1948. It quotes Walter Horten's view that the Russians may have found the Horten IX blueprints at the Gotha factory, and a May 1948 memo saying "Walter Horten has admitted his contacts with the Russians".^[5] Her account links the hunt to a Roswell disc bearing Russian writing.^[5] The Pretty memo itself does not mention Roswell.^[1]

The memo

• The memo came from the S-2 (intelligence) branch of Headquarters Berlin Command, Office of Military Government for Germany (US). It was addressed to the Deputy Director of Intelligence, European Command, in Frankfurt, with a copy to the Director of Intelligence, OMGUS, and was signed by Lieutenant Colonel Harry H. Pretty.^[1] The timeline describes it as going to the deputy G-2 in Berlin, and calls the aircraft the "Ho 299".^[7] The memo itself shows Frankfurt and the "Horten IX".^[1]
• The brothers. Both lived in Göttingen but travelled widely. Walter was looking for work in Bavaria and may have contacted USAFE headquarters in Wiesbaden about going to the United States under "Paper Clip". Reimar was finishing a doctorate in advanced mathematics at Bonn and planned to teach at Braunschweig.^[1] The memo called both "exceedingly peculiar". It described Reimar as the theorist behind the flying wing and Walter as the engineer who tested his "somewhat fantastic ideas" against practical calculations, and said the two quarrelled constantly.^[1]
• The Horten IX. According to the memo, Walter built the Horten IX alone, by fitting BMW jet engines to the Horten VIII design. It was made of plywood with a Messerschmitt Me 109 landing gear. A model was tested in the wind tunnel at Göttingen in late summer 1944 under Professor Betz, who opposed flying wings. Two were flown at Rechlin in autumn 1944. One crashed when an engine failed, killing its pilot, while the test pilot Eugen flew the other at about 950 km/h without trouble.^[1]
• Production. Göring ordered immediate production at Gothaer Waggon Fabrik in January 1945, asking for ten aircraft at once. Production never started. The memo says the firm's technical manager, Berthold, kept proposing changes, apparently to make the design his own.^[1] Other sources give different details: an order for 40 aircraft, first flights of the jet prototype in December 1944 or February 1945, and a fatal crash on 18 February 1945.^[3]
• After the war. When U.S. troops took Gotha the factory's plans were hidden. The Hortens' own plans, hidden in a salt mine at Salzdettfurt, were recovered by the British in summer 1945. The brothers, Betz and two test pilots spent about 90 days being questioned in England, where Reimar refused to cooperate without a contract. Walter was paid by the British from October 1945 to April 1946.^[1]
• In 1947 Walter wrote to Northrop about a job. Northrop replied that he could not bring him over himself but would welcome him, and advised him to contact USAFE for clearance.^[1]

The findings

• No Soviet contact. According to the memo's source, neither brother had any contact with the Soviet air force or another foreign power, and Reimar was thought unlikely to sell out to the Soviets. The only possible link was the full set of Horten IX plans hidden at the Gotha factory, which Berthold and other engineers knew about. Investigators thought it "possible and likely" that one of them might have passed the plans to the Soviets, and said this would be checked.^[1]
• No flying saucer design. To check whether any German research institute had ever planned a "flying saucer", investigators separately contacted Walter Horten; his wife, Fräulein von der Groeben, a former chief secretary to Air Force General Udet; Guenter Heinrich, formerly of the Luftwaffe high command's research office; Professor Betz, former chief of the aerodynamic institute at Göttingen; and the test pilot Eugen. All said that to their knowledge "no such design ever existed nor was projected by any of the German air research institutions". They agreed such a design "would be highly practical and desirable".^[1]
• The earlier version of this article described one interviewee simply as a former secretary to General Ernst Udet. The memo identifies her as Walter Horten's wife and gives no first names for Udet or Betz.^[1]

Significance

• The memo is one of the clearest early documents against the later "Nazi UFO" legend, according to which Germany secretly built flying saucers, sometimes said to have survived in hidden bases. That legend grew from 1950 onwards through claims by people such as Rudolf Schriever and Georg Klein, and later through fiction about "Haunebu" and "Vril" craft.^[2][1]
• The Horten flying wings themselves were real and influential. In 1983 Reimar Horten claimed he had planned to add charcoal dust to the glue to absorb radar, which led to later claims that the aircraft was an early stealth design.^[3] Project 1947 lists the memo among its collection of 1947 UFO documents.^[4]

People and topics

• Horten brothers — German aircraft designers of the Ho 229 jet flying wing, investigated in 1947 as a possible source of the discs.
• Unidentified flying object — An object in the sky that can't be identified; the older term for UAP.
• U.S. Air Force — The U.S. military service that ran the official UFO projects from 1947 to 1969.
• Harry H. Pretty — Army intelligence officer in Berlin who wrote the December 1947 memo on the Horten brothers.

On the Timeline

• Mexican mystery missile (1947) (October 1947) — An unknown missile allegedly crashes in Mexico and the State Department is said to seek the wreckage.
• Laredo UFO crash claim (1948) (1948) — An anonymous retired colonel claims a craft crashed near Laredo, Texas, and witnesses were sworn to secrecy.

See every 1947 event on the UAP Timeline →

Further reading

References

Facts in this article are drawn in part from the Wikipedia articles “Nazi UFOs”, “Horten Ho 229”, available under the CC BY-SA 4.0 licence.