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UAP LEDGER
Department of War

341_110448_Records_Relating_to_the_Collection_and_Dissemination_of_Intelligence_1948-1955-TS_CONT_No.2_2-5300-2-5399

Released: May 8, 2026

Written by AI from official sources, checked against them before publishingHow we do this

This classified Air Force intelligence report from November 1948 describes two separate incidents involving unidentified objects observed by U.S. military personnel in Europe. The first was an unidentified aircraft spotted by bomber crews off the Dutch coast; the second involved recurring reports of flying saucers, including one observed near a Swedish lake. The document shows how U.S. intelligence officers were grappling with these sightings and considering various explanations.

What was the unidentified aircraft sighting?

On September 5, 1948, three crews from the 307th Bomb Group spotted an unidentified aircraft off the west coast of Holland at 30,000 feet. The object was initially cruising at normal jet speed before it began leaving smoke and condensation trails, then accelerated and climbed sharply. The observers concluded it was likely a single jet-propelled aircraft with rocket assistance, possessing more power than known jets of 1947. The Air Force rated this sighting as B-2, meaning it remained unidentified.

What did U.S. intelligence say about flying saucers?

U.S. Air Force intelligence officers in Europe reported being concerned about recurring flying saucer reports from many sources and locations. They noted that one object hovered over Neubiberg Air Base for about thirty minutes. The officers acknowledged these reports could not be ignored and needed explanation, though they admitted the subject was "slightly beyond the scope of our present intelligence thinking."

What was the Swedish theory?

When U.S. Air Force officers visited Swedish Air Intelligence, the Swedes shared their assessment that flying saucers showed "a high technical skill which cannot be credited to any presently known culture on earth." Swedish officials believed the objects might originate from "some previously unknown or unidentified technology, possibly outside the earth." They cited an observation by a Swedish technical expert near a lake where an object reportedly crashed or landed. Swedish intelligence was confident enough in this observation to send a naval salvage team. Divers discovered a previously uncharted crater on the lake floor, though operations were still underway when the U.S. officers visited and final results were pending.

How did U.S. intelligence respond to these theories?

U.S. Air Force officers stated they were "inclined not to discredit entirely" the Swedish theory about extraterrestrial origin, while keeping an open mind on the subject. However, they also noted that accepting such a theory would raise "a whole new group of questions" and change much of their thinking. The cautious language suggests the officers viewed the theory as speculative and extraordinary, not as a likely explanation.

Full Document Text

Text extracted directly from the source PDF. Text extraction via abigailhaddad/ufo-releases; original file at war.gov.

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BE                                 ~!;
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             USAFE 2         TT 1524            S!CRE'f                    4 Nov 48
             To Gen Cabell
                   We now have one complete set of all reports prepared by special

             intelligence organization of the European Command from its conception to
             present date.    We are forwarding these reports for your inspection and

             final disposition.    We are of the opinion that inspection of these reports
             will lend weight to arguments for allocating Air Force funds to this

             organization.     Advise caution in utilizing these reports as mst of them.
             were forwarded as received.


             {END OF ITEM)




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USAFE 10        'lT 1524    OONPIDEN!:I:AL      4 Nov 1948
             From OI OB
                   Following report on unidentified aircraft sighting comes from 307th Bomb
             Group which participated in operation daggar.     Unidentified aircraft was
             sighted by three crews of the group at 14022 5 Sep 48 off west coast of Holland,
             5155N/0355E. Altitude of all aircraft was 30,000 feet. When first sighted
             the unidentified A/C was cruiamng at a normal jet speed, heading 120 degrees.
             Soon after f'ir~t. seen, A/C began leaving smoke trails and condensation trails
             accompanied by sudden acceleration and then climb.     Generali agreed by
             observers that it was a single jet propelled A/C employing probably rocket
             assists with tremendous reserve power, more than normal curising speed tor
             jets of the 1947 variety.     Never within identification range; its course
             did not indicate its purposeo
             Our evaluation of the above:     B-2.
             (iND OF ITDI)




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TOP SECRET

                        USAFE l4        ff 1524   !OP SSCRET           4 Nov 1948


            From OI OB
                  For some time we have been concerned by the recurring reports on .f'lying
            saucers. They periodically continue to cbp up; during the last week., one was
            observ·ed hovering over Neubiberg Air Base tor ab:>ut thirt-7 minutes. Th9J'
            have been reported by so many sources and from such a variet7 of places that
            we are convinced that they cannot be disregarded and mu.st be explained on eom.e
            basis wh.£ch is perhaps slightly beyond the eeope o t our present intelligeace
            thinking O                            •




                 When officers of this Directorate recently visited the Swedieh Air
            Intelligence Service. This question was put to the Swedes. Their answer
            was that soma reliable and fully technically qualified people have reached
            the conclusion that "these phenomena are obviouel;r the result of a high
            ••ohnical skill which cannot be credited to any- presently known culture on
            e~.n Thq1are therefore assuming that these objects originate from eome
            previous4" unknown or unidentified technology, possibly outside the earth.
                  One of these objects was observed by a Swedish technical expert near
            his .home on the edge of a lake. The object crashed or landed in the lake
            and he car16ully noted its azimuth trom his point or observa:tion. Swedish
            intelligence was sufficiently confident in his observation that a naval
            salvage team was sent to the lake. Operations were 'Wlderw81' during the
            visit ot USAF1~ officers. Divers had discovered & previosul.y uncharted
            crater on the floor ot the lake. No further information is anilable, bat
            we have been promised knowledge of the resultao In their opinion., the
            observation was reliable, and they- believe that the depress.ion on the floor
            ot the lake, 'Which did not appear on current IJdrographic charts, was in
            fact caused by a flying saucer.                      •
                  Although accepting this theory of the origin of these objects posea a
            who,le new group of questions and puts much of our think:i.ng in a changed
            light, we are inclined not to discredit entirely this somewhat spectacular
            theory, meantime keeping an open mind on the subject. What are your
            reactions?
            TOP
            (Effl) OF USAPB ITEM: 14)




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View the official file

Frequently Asked Questions

What did the 307th Bomb Group observe on September 5, 1948?

Three crews from the 307th Bomb Group spotted an unidentified aircraft off the west coast of Holland at 30,000 feet altitude. The object was initially cruising at normal jet speed, then began leaving smoke and condensation trails before accelerating and climbing sharply. Observers concluded it was likely a single jet-propelled aircraft with rocket assistance and more power than known jets of 1947. The sighting remained unidentified.

From the source, word for word
Unidentified aircraft was sighted by three crews of the group at 14022 5 Sep 48 off west coast of Holland, 5155N/0355E. Altitude of all aircraft was 30,000 feet. When first sighted the unidentified A/C was cruiamng at a normal jet speed, heading 120 degrees. Soon after f'ir~t. seen, A/C began leaving smoke trails and condensation trails accompanied by sudden acceleration and then climb.

Check it against the official file

Why were U.S. intelligence officers concerned about flying saucer reports?

U.S. Air Force intelligence officers in Europe reported that flying saucer reports had been recurring for some time and came from many sources and varied locations. One object was observed hovering over Neubiberg Air Base for about thirty minutes. The officers stated these reports could not be disregarded and must be explained, though they acknowledged the subject was beyond the scope of their current intelligence thinking.

What did Swedish Air Intelligence believe about flying saucers?

Swedish Air Intelligence officials told U.S. officers that reliable and technically qualified people had concluded flying saucers displayed technical skill that could not be credited to any known earthly culture. They theorized the objects might originate from previously unknown or unidentified technology, possibly outside Earth. They based this partly on an observation by a Swedish technical expert who reported an object crashing or landing in a lake near his home.

From the source, word for word
Their answer was that soma reliable and fully technically qualified people have reached the conclusion that "these phenomena are obviouel;r the result of a high ••ohnical skill which cannot be credited to any- presently known culture on e~.n Thq1are therefore assuming that these objects originate from eome previous4" unknown or unidentified technology, possibly outside the earth.

Check it against the official file

What happened when Swedish intelligence investigated the lake incident?

Swedish intelligence was confident enough in a technical expert's observation of an object crashing or landing in a lake that they sent a naval salvage team. Divers discovered a previously uncharted crater on the lake floor. However, operations were still underway when U.S. Air Force officers visited, and no final results were available at the time the report was written.

From the source, word for word
Swedish intelligence was sufficiently confident in his observation that a naval salvage team was sent to the lake. Operations were 'Wlderw81' during the visit ot USAF1~ officers. Divers had discovered & previosul.y uncharted crater on the floor ot the lake.

Check it against the official file

Congressional Context

No confirmed links between this file and the congressional record yet. Connections are added only when the source text supports them, never inferred.