US Coast Guard cutter Sebago heading NNE at 23° azimuth tracked radar target to the south, about 200 miles south of Mobile, Alabama, at 188° azimuth range 22 miles traveling at 650 mph disappearing at 190° azimuth at 55 miles range. Visual object like a brilliant planet was seen at 5:21 for five seconds traveling left to right from west to northwest from 270° to 310° azimuth at about 31° elevation. A radar target seemingly stationary for one minute at 5:20-21 to the north at 350° azimuth range seven miles moved slowly towards the northeast then accelerated rapidly off the scope at 15° azimuth (about NNE) at 175 miles.

Ruppelt's account:

…when the Coast Guard Cutter Seabago radioed in their report from the Gulf of Mexico wheels began to turn--fast.

On Tuesday morning, the 5th, the Seabago was about 200 miles south of the mouth of the Mississippi River on a northerly heading. At 5:10A.M. her radar picked up a target off to the left at a distance of about 14 miles. This was really nothing unusual because they were under heavily traveled air lanes.

The early morning watch is always rough and as the small group of officers and men in the Combat Information Center quietly watched the target, with a noticeable lack of enthusiasm, it moved south, made a turn, and headed back to the north again. A few of the men noticed that the turn looked "a little different," but this early in the morning they didn't give it much thought.

At 5:14 the target went off the scope to the north.

At 5:16 it was back and the lassitude was instantly gone. Now the target was 22 miles south of the ship. No one in the CIC had to draw a picture. Something, in two minutes, had disappeared off the scope to the north, made a big swing around the ship, out of radar range, and had swung in from the south!

Word went up to the lookouts. They tensed up and began to scan the sky.

The radar contacts continued.

This second contact, south of the ship, was held for two full minutes as the target moved out from 22 to 55 miles. Then it faded.

At 5:20 the target was back but now it was north of the ship again, and it was hovering!

Again the lookouts were called. Could they see anything now? Their "No" answers didn't hold for long because seconds later their terse reports began to come into the CIC. A "brilliant light, like a planet" was streaking across the northwest sky about 30 degrees above the horizon. Unfortunately the radar had lost contact for a moment when the visual report came in.

At 5:37 the target disappeared from the scopes and was gone for good.

156-B. Gulf of Mexico, Coast Guard Cutter "Sebago," 25"47'N 89° 24'W, 5 November 1957, 0510-1537 LST. Weather : not given, but apparently some clouds in area. The most applicable radio refractivity data available are for Key West, Fla. 0600 and 1800 LST, 5 November 1957. They are shown in Figs. 22 and 23. One visual and three radar objects were included in this case. The ship's heading was 23° true. The first contact was a radar blip picked up at 0510 LST at 290° true azimuth, 14 mi. It moved south, approached the ship within 2 mi., and returned north along ship's port side. Contact was lost at 0514 LST. Average speed of this UFO was calculated as 250 mph. At 0516 LST a new blip was picked up at 188°, 22 mi.; this target departed at a computed 650 mph., disappearing at 0516 LST at 190°, 55 mi. The third radar target was acquired at 0520 LST at 350°, 7 mi.; it appeared to be stationary. While the third radar target was being watched on the scope, a visual object was observed for about 3 sec. at 0521 LST travelling from south to north at about 31° elevation between 270° and 310° azimuth. The third radar target remained stationary for about 1 min. and then slowly moved to the northeast, finally accelerating rapidly and moving off scope at 15°, 175 mi

The visual object was described as "like a brilliant planet;" it was undoubtedly a meteor, and in any event obviously was unrelated to radar target number three, the only radar target visible at the same time.

The radar targets were, with the possible exception of the first one, erratic and unpredictable in their movements. The second and third radar blips appeared suddenly, well within the normal pick-up range of the ship's radar. These two blips were probably caused by anomalous propagation. The two Key West profiles, although taken at some distance from the ship's position, are indicative of rather unusual atmospheric conditions in the area. Indeed, the 1800 LST profile is probably one of the most unusual radio refractive index profiles that has ever been observed. The atmospheric structure was apparently one of alternating very wet and very dry layers. Patterns of this sort are often very stable in these subtropical latitudes, and tend to extend in rather homogeneous form over large horizontal distances. The ray-tracing of this profile, Fig. 23a, shows even greater changes in ray curvature. Strong partial reflections should be expected under these conditions.

The first radar target behaved generally like an aircraft, and the AF investigators were of the opinion that it was an aircraft, probably from Eglin AFB to the north.

In summary, the weight of evidence points toward anomalous propagation as the cause of the radar echoes, the first possibly being an aircraft. The visual object was apparently a meteor.

Coincidentally, the ship, SS Hampton Roads, at 27° 50'N 91° 12'W sighted a round, glowing object high in the sky that faded as darkness approached at 1740-1750 LST. This object appeared to move with the upper winds. AF investigators concluded that it was in all probability a weather balloon.

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