The following pdf file is housed on the NICAP site for security reasons. The documents were provided by Keith Chester and searchable text of that file presented below produced by Rich Vitello.


Alaskan Air Command
APO 942 c/o Postmaster
Seattle, Washington

Authority 0017218
by KJ NARA Date 01/09/09
                                22 April 1948                                                             

AAOIN-3 312

Subject: Unusual Sightings along Aleutian chain

TO : Director of Intelligence
        United States Air Forces
        National Defense Building
        Washington 25, D.  C.

1.  Beginning 8 March 1948 numerous sightings have been
 made in waters surrounding the Aleutian Islands by aircraft
 of this command.  The following report is a summary of all
 the unusual sightings made to this date.

    1st sighting - 8 March 1948

    during a routine flight from Davis Air Force Base to Shemya Air Force Base at 090050Z, the pilots of
    aircraft AF5889 observed a black superstructure protruding the surface of the ocean at 177 40' E; 51
    57'N.  The pilots recognize the object as a submarine and immediately headed in its direction at
    an altitude of 500 feet above sea level.  When approximately 8 miles from the cited object and after
    five minutes of continuous observation, the object submerged on 120 heading, creating a large area of
    foam and leaving a wake which appeared to be three times the length of the cited object.  A thorough
    visual search was made in the area where the object submerged with negative results.  It was reported
    simultaneously when he was attempting to make voice contact with Shemya radio on 4220 kcs.

    The weather at the time of the observation was as follows: visual contact condition 20 miles visibility,
    choppy sea with occasional whitecaps, surface winds 12 to 15 knots

Page 2


BASIC : Ltr to Dir of Intelligence, USAF, Unusual Sightings
    along Aleutian Chain, 22 April 48.

    2nd Sighting - 10 March 1948

    While on a local flight from Davis Air Force Base at 1945Z, the pilots of aircraft AF 6368
    observed a blue-white flare ascend from the south tip of Tanaga Peninsula (177 55'W; 51 35'N) to
    a height of 7000 feet, dropping off sharply and falling to the ground in a deep orange color.  The
    observation was made 18 miles away at 7000 feet.  The duration of the observed light was approximately
    5 seconds.

    3rd Sighting - 10 March 1948
    While on a routine flight to Cape Air Force Base, Umnak Island, Alaska, the pilots of aircraft AF 2537
    observed from 5 miles distance and 3000 feet a white vessel at 167 50'W, 53 27'N proceeding outbound
    from the shore of Umnak Island on a course of 30.  No curiosity arose upon the sighting of the vessel,
    except that it appeared to be proceeding exceptionally fast with a long narrow wake trailing behind.
    (Interest was taken on the above report for the following reason: the shape of the vessel as described by
    the pilot was identical to the description as submitted by the pilots of #1 sighting, who sighted an object
    which resembled a submarine.)

    Whether at the time of observation was ceiling and visibility unlimited.

    4th  Sighting - 13 March 1948
    While on a routine cargo flight, the pilots of an aircraft of this command sighted from 8000 feet and between
    breaks in a broken cloud layer, two black objects on the surface of the water (55 58' N; 160 50'W and 55 56'
    N; 160 54'W) which to them appeared to have the shape of a submarine conning tower.

    5th Sighting - 2 April 1948

    Surface radar contact was made by a Navy patrol aircraft operating from Kodiak, Alaska while at 1000 feet
    altitude, in position 53 03'N; 170 351'W at 0115Z.

Page 3

BASIC:    Ltr to Dir of intelligence, USAF, unusual sightings along the Aleutian chain, 22nd April 48.

    Target was under observation while aircraft proceeded from 19 miles to 4 miles of target where it
    disappeared from scope.  A thorough visual and radar search was made with negative results.

    The weather at the time of the observation was: visibility 15 miles, southeast wind at 18 mph.

    6th Sighting - 3 April 1948

    The commanding officer of Naval vessel ATA192 reported a surface radar contact at 0305Z while in
    position 53 05'N; 171 10'W.  True bearing of target was 330 at 13 miles distance.  Target bearing
    remained constant for 25 minutes in the distance decreased to 11 miles, then disappearing from scope
    at 0330 Z.

    The weather at the time of observation was: visibility 5 to 8 miles, 10 foot seas.

    7th Sighting - 7 April 1948

    On a scheduled flight from Fort Glenn to Adak, Alaska, the pilots sighted from 5000 feet at 072254Z an
    unidentified surface object in the vicinity of the Koniuji Islands.  (52 14'N; 175 05'W).  Object
    appeared to be a small vessel proceeding on a heading of 120.  Upon closer inspection, object
    appeared to be submerging and trailing a narrow wake.

    8th Sighting - 10 April 1948

    Ground Control Approach radar operator at Shemya Air Force Base, Shemya, Alaska made a positive radar
    contact from 0750Z to 0812Z and 0907Z to 0920Z.  The range and azimith of the target was 8 1/2 miles
    at 172.    The known altitude coverage of radar at above range was 1000 to 4000 feet and the
    bearing was 95 magnetic.  The approximate speed of the target was 14 to 16 knots.
    The weather at the time of the observation was: Ground fog.

    2.  The following operational action was taken as a result of the above sightings.

Page 4

    BASIC: Ltr to Dir of Intelligence, USAF, unusual sightings along Aleutian Chain, 22 April 48.

    1st Sighting

    Three Navy privateers dispatched from Adak, Alaska to search area at dawn on 9 March 1948.

    Results: Negative.

    4th Sighting

    Navy reconnaissance conducted on 16 March 1948.  Results indicated one large grayish-brown building
    55 56'N; 161 19'W.  Building had two adjacent derreck-like structures about 50 feet high.
    Pilot who made No, 4 sighting made reconnaissance of area in which he sighted objects on 19 March 1948
    area which the pilots searched and reported seeing objects did not correspond with the area the Navy
    reported were not there when he conducted search on 19 March 1948.

    1st, 2nd, 3rd, 4th Sightings

    Field orders were issued to the's 72nd Photo Reconnaissance Squadron (VLR) and long-range reconnaissance
    was conducted on 17 March 1948, with the following results: No positive targets sighted.  Visual search
    made in the area No.  1 and No.  4 sightings.  Radar search in area of No.  3 sighting.  No.  1 sighting
    area not completely covered due to lack of fuel and strong winds aloft.  Three partially sunk Japanese
    vessels sighted in Kiska Harbor and one in Gertrude Cove, Kiska Island.

    Reconnaissance scheduled for 18 March 1948 was canceled due to deep snow on the Ladd Field runways.

    5th Sighting

    Visual and radar search made immediately by same aircraft which made sighting.

    Results: Negative.

    5h and 6th Sightings

    Detailed reconnaissance conducted by Navy Privateer from NOB Kodiak on for April 1948 between 169 W.-
    174 W.  Aircraft

Page 5

BASIC: Ltr to Dir of Intelligence, USAF, unusual sightings along Aleutian Chain 22 April 1948.

    Equipped with Sono Bouys.

    Results: Negative.

    7th Sighting

    Navy PB4Y aircraft proceeding on the same course as reporting aircraft, and twelve minutes flight time to the
    East, intercepted message and requested reporting aircraft to indicate last observed position of surface
    craft.  Navy PB4Y prepared Sono Buoy pattern and detected sounds similar to that made by undersea's craft.
    Two or three whales were observed surfacing and submerging within the Sono Buoy pattered.  Listening device
    operator was able to differentiate between sounds attributed to the whales and that of the machinery-like
    turn.  PB4Y remained in general vicinity for approximately one hour.

    8th Sighting

    No action taken.

    3.  In order that object sighted as those described above can be more positively identified, it is now a
    standard operating procedure with all scheduled aircraft flying the Aleutian Chain to carry one pair of
    binoculars and one loaded K-20 camera.  Instructions have been given to aircrews to utilize the binoculars
    for search and to get photos of all unidentified objects sighted with the K-20 camera.

                            A.M. Clark
                            Lt. Colonel, USAF
                            Director of Intelligence