Wednesday 21 March 2018

UFO Case Directory (RADCAT):
“Key Radar Case (CCL #17)
July 29, 1952
20 mi W. of Port Huron, Michigan”


(NICAP.org)

The whole UFO case report:
Fran Ridge:
This report is case #17, on the official clearance list of 41 formerly classified Air Technical Intelligence UFO reports cleared for Maj. Donald E. Keyhoe by Albert M. Chop, Air Force Press Desk.

Brad Sparks:
July 29 [28?], 1952.  20 miles W of Port Huron, Mich (at 43.0° N, 82.8° W).
9:40-10 p.m. (EST).  One of 3 USAF F-94B's on an ECM exercise at 9,000-9,500 ft from 61st FIS at Selfridge AFB climbed to 20,000 ft on a 270° heading when it was vectored to a UFO headed S [or SE?] at 625 mph from Saginaw Bay by GCI air defense radar [apparently FPS-3, Port Austin AFS, Mich.] (callsign ‘Avenger’) [tracked about 7 mins evidently].  Ground radar told pilot Capt. Edward J. Slowinski (Sloan) to look at his 3 o’clock low position for a target (to the N), but found nothing, then told to look at 3 o’clock high (radar man recalled ‘low’ then ‘high,’ pilot said he was told ‘high’ then ‘low’).  F-94 turned right to pursue [~9:47 p.m.].  Object suddenly reversed course with a tight 180° turn back N on ground radar scope [evidently at 300 mph to match F-94’s speed, in a visible loop on the radar scope on a right turn paralleling the F-94’s right turn but tighter].  As the F-94 continued right turn, radar observer Lt. Victor Helfenbein picked up target at 4 miles range on APG-33 airborne radar, level with jet altitude, at 60° relative or 2 o’clock (about 330° to 360° azimuth depending on how far into the turn) (pilot said Helfenbein reported 2:30 o’clock).  Airborne radar contact made [for possibly 20 secs during the turn] then at dead ahead 12 o’clock position radar got lockon for 30 secs until target ‘jumped lock’ when it apparently almost doubled its 4-mile [or 4-5 mi] distance in one sweep of the ground radar accelerating to 1,400 mph average speed [4-mile jump in 10-sec sweep of radar, thus reaching peak 2,600 mph at about 20 g’s].  Jet briefly put on afterburner to try to close distance with object on 360° heading at 21,000 ft increasing speed with afterburner to about 350 knots IAS (about 490 knots TAS or 560 mph) [for about 3 mins?], but object would put on a burst of speed and pull away from the jet.  F-94 pilot first saw multiple lights ahead as if from a jet aircraft, but no exhaust or trail, and followed the GCI vectoring to target ahead between 12 o’clock and 1 o’clock positions.  Object appeared ‘many times larger than a star’ then ‘took on a reddish tinge, and slowly began to get smaller, as if it were moving away,’ and changed color from reddish then bluish-green then white then red again in sequence (both crew members in agreement) low on the horizon to the N (possibly the star Capella and unrelated to radar target, though Helfenbein was an expert celestial navigator since 1943 with 1,400 flying hours and had never seen anything ‘like this before’; also another F-94 followed same N route about 10:30 p.m. with Capella still visible but did not see it as unusual or anything else).  F-94 continued N heading [for about 5 mins] at about 300 mph as object maintained lead at 6-10 miles range, with GCI telling F-94 crew they were not gaining on the target on scope.  Chase ended with F-94 about 5 miles N of peninsula (map shows 10 mi ENE of Burnt Cabin Point at 44°07’ N, 82°45’W) return due to low fuel, object then slowed to 200-300 mph before disappearing after another 1-2 mins.  (Sparks;  McDonald 1968;  McDonald papers;  Mary Castner/CUFOS;  Loren Gross July 21-31, 1952 SUPP pp. 71-77;  Ruppelt pp. 171-172, 190;  BB Status Rpt 8, pp. 27-28, in NARA Roll 85, p. 701-2, Maxwell Roll 1, pp. 674-5;  Todd Lemire) 

Capt. Edward J. Ruppelt:
......  less than six hours after the ladies and gentlemen of the press said ‘Thank you’ to General Samford for his press conference, and before the UFO’s could read the newspapers and find out that they were natural phenomena, one of them came down across the Canadian border into Michigan. The incident that occurred that night was one of those that even the most ardent skeptic would have difficulty explaining. I’ve heard a lot of them try and I’ve heard them all fail. (RUFOS, 171)”

NICAP.org presents several U.S. government documents (U.S. Air Force) that pertain to the case.

http://www.nicap.org/520729porthuron_dir.htm













(wikimedia.org image)


















Satellite photo of Port Huron, Michigan (tageo.com)
(tageo.com photo)