*DATE: August 26, 1947            TIME: local                     CLASS: R/ground radar

LOCATION:                  SOURCES:  Air Defense Command, Air Intelligence Reports, Jan. 1948

Fukuoka                                              Air Intelligence Reports


            RADAR DURATION:

            (6 separate episodes)

EVALUATIONS:  Project SIGN - no explanation

                                Air Intelligence Division, HQ USAF Intel/Office of Naval Intelligence--unknown/Soviet  aircraft,

                                Defensive Air Branch, Air Intel Div, HQ USAF Intel - Possible Soviet photographic mission

                                FEAF - Soviet Jet Aircraft

Air Intelligence Report serial numbers: KO-89816,  KO-91052

Added Case: Aldrich

INITIAL SUMMARY: Extract from AAir Intelligence Reports@ January 1948, published by the Air Defense Command, page 6-7 of AE@:

                                                    POSSIBLE SOVIET JET AIRCRAFT RADAR SIGHTINGS

      Report of a radar sighting of a high speed (480 mph) unidentified target, on 28 August 1947 by Fukuoka M-E-W radar station.

     On 28 August 1947 at 1640 Item time Radar Station No. 1 sighted and plotted an unidentified aircraft moving at an estimated speed of 450-480 mph.  Target orbited several times 30 to 35 miles out a heading of 20-30 degrees from the station; then headed out on 23 degrees course, fading at 62 miles.

     Weather at time of sighting was broken overcast, 1000-1500 foot ceiling.

     Altitude was not determined nor were fighters alerted, due to short duration of plot.  Aircraft was first picked up on low beam, indicating that it was at 1500 feet or below; then appeared distinctly on high beam on its outward track.

    The above information is evaluated A-2, as the radar team operating at the time of the incident is considered to have a high level of experience and skill.

           FEAF COMMENT

    Radio report was furnished assessing the observation as a possible Soviet jet aircraft.

   Observation was made on an AN/CPS-1 set.

   No confirming reports of this sighting have been received from any other source.  A radar sighting of an unidentified high speed target was made by the GCA station at Chitose AAB on 1 July 1947.

     If assessment of this sighting [Fukuoka 26 August 1947] as a possible Soviet jet aircraft is correct the location of        the sighting would make North Korea its most logical base.  The only report received which might indicate the basing       of Soviet high speed aircraft in North Korea is an F-3 report of a new type Soviet aircraft observed at Haeju airfield. In the case of the Chitose sighting, southern Sakhalin was considered to be the target=s most logical base.

KO 91052                                              Not Evaluated Secret

NOTES:   The Defensive Air Branch, Air Intelligence Division, HQ USAF Intelligence in Memorandum for the Assistant Chief of Staff  - 2, Subject: Radar Pick-ups of High Speed Targets in the Far East, dated 26 September 1947 concluded that this sighting might be Soviet jet as it was believed at the time that the Soviet aircraft had sufficient performance to exhibit the characteristics reported.