Jan. 24, 1949; About 250 miles SW of Bermuda Island, Atlantic (BBU)
12:00-2:10 a.m. (Z/GMT/UT)  USAF pilot Capt. Marsden W. Mattatall and crew (copilot 1st Lt Frank J. Stockton, navigator Lt. Austin, S/Sgt Joseph D. Marx, S/Sgt Leonard G. Lerch, Sgt Sims) of RB-29 bomber no. 44-87750 in the 373rd Recon Sq (Very Long Range - Weather) based at Kindley AFB, Bermuda [on classified Atomic Detection System service] searching for lost BOAC Tudor IV airliner Star Ariel, at 1,500 ft heading 50° True (about NE) [at 200  mph] saw to the left (in the N) a red glow on the ocean 1 to 1-1/2 miles in size extending up to 2,500-3,000 (or 4,000-6,000) ft altitude with 2-4 white searchlight-like beams of light within the red glow.  At 12:25 a.m. B-29 turned toward the light on heading 350° True and by 12:40 approached so close, estimated 100-150 ft [?] distance at 6,000 ft altitude at 31°24' N, 67° 8' W, that pilot made a sharp bank to avoid collision. B-29 crew unable to take nuclear fallout sample of air around red glow because in haste to take off on search mission they failed to bring filter paper.  B-29 circled the red glow from all directions for 44 mins as the glow slowly moved to 31°25' N, 67° 14' W [at about 10 mph headed W], when they finally departed the area at 1:24 a.m.  Red glow still visible on landing in Bermuda [at about 2:10 a.m.].  Crew took 15 (?) photos with K-20 camera set at 1/125th sec and f/4.5 aperture, but none were sensitive enough to show the red light.  Later RB-29 (?) flight equipped with fallout filters visited the coordinates of the red glow at 11:00 a.m. but results of air sampling not known or reported.  AMC Intell Dept Chief Col. William R. Clingerman ordered references to "filtering" deleted from sighting reports as the would "unnecessarily disclose classified Air Force operations."  (BB Maxwell Microfilm Roll 5 pp. 167-233;  Project 1947;  Saunders/FUFOR Index) 2 hrs 10 mins 6? witnesses 100 Full Moons nuclear monitor flight