Vinther DC-3 (Case 3)
Sioux City, Iowa
January 20, 1951
By Dr. James E. McDonald:

Another of the many airline-crew sightings of highly unconventional aerial devices that I have personally checked was, like Cases 1 and 2, widely reported in the national press (for a day or two, and then forgotten like the rest). A check of weather data confirms that the night of 1/20/51 was clear and cold at Sioux City at the time that a Mid-Continent Airlines DC-3, piloted by Lawrence W. Vinther, was about to take off for Omaha and Kansas City, at 5 :20 p.m. CST. In the CAA control tower, John M. Williams had been noting an oddly maneuvering light high in a westerly direction. Suddenly the light abruptly accelerated, in a manner clearly precluding either meteoric or aircraft origin, so Williams alerted Vinther and his co-pilot, James F. Bachmeier. The incident has been discussed many times (Ref. 4, 5, 10, and 28), but to check details of these reports, I searched for and finally located all three of the above-named men. Vinther and Bachmeier are now Braniff pilots, Williams is with the FAA in Sacramento. From them I confirmed the principal features of previous accounts and learned additional information too lengthy to recapitulate in full here. 

The essential point to be emphasized is that, shortly after Vinther got his DC-3 airborne, under Williams' instructions to investigate the oddly-behaving light, the object executed a sudden dive and flew over the DC-3 at an estimated 200 ft. vertical clearance, passing aft and downward. Then a surprising maneuver unfolded. As Vinther described it to me, and as described in contemporaiy accounts, the object suddenly reversed course almost 180-degrees, without slowing down or slewing, and was momentarily flying formation with their DC-8 off it's port wing. (Vinther's dry comment to me was: "This is something we don t see airplanes do.") Vinther and Bachmeier agreed that the object was very big, perhaps somewhat larger than a B-29, they suggested to newspapermen who interviewed them the following day. Moonlight gave them a good silhouetted view of the object, which they described as having the form of a fuselage and unswept wing, but not a sign of any empennage, nor any sign of engine-pods, propellers, or jets. Prior to its dive, it had been seen only as a light; while pacing their DC-3, the men saw no luminosity, though during the dive they saw a light on its underside. After about five seconds, the unknown object began to descend below them and flew under their plane. They put the DC-3 into a steep bank to try to keep it in view as it began this maneuver; and as it crossed under them, they lost it, not to regain sight of it subsequently. 

There is much more detail, not all mutually consistent as to maneuvers and directions, in the full accounts I obtained from Vinther, Bachmeier, and Williams. The dive, pacing, and fly-under maneuvers were made quickly and at such a distance from the field that Williams did not see them clearly, though he did see the object leave the vicinity of the DC-3. An Air Force colonel and his aide were among the passangers, and the aide caught a glimpse of the unknown object, but I have been unable to locate him for further cross-check. 

Discussion. - The erratic maneuvers exhibited by the unknown object while under observation from the control tower would, by themselves, make this a better-than-average case. But the fact that those maneuvers prompted a tower operator to alert a departing aircrew to investigate, only to have the object dive upon and pace the aircraft after a non-inertial course-reversal, makes this an unusually interesting UFO. Its configuration, about which Vinther and Bachmeier were quite positive in their remarks to me (they repeatedly emphasized the bright moonlight, which checks with the near-full moon on 1/20/51 and the sky-cover data I obtained from the Sioux City Weather Bureau), combines with other features of the sighting to make it a most significant case The reported shape (tailless, engineless, unswept aircraft of large size) does not match that of any other UFO that I am aware of; but my exposure to the bewildering range of reported configurations now on record makes this point less difficult to assimilate. This case is officially carried as Unidentified, and, in a 1955 publication (Ref. 29), was one of 12 Unidentifieds singled out for special comment. A contemporary account (Ref. 28), taking note of a then recent pronouncement that virtually all UFOs are explainable in terms of misidentified Skyhook balloons, carried a lead caption. "The Office of Naval Research claims that cosmic ray balloons explain all saucer reports. If so, what did this pilot see?" Certainly it would not be readily explained away as a balloon, a meteor, a sundog, or ball lighting. Rather, it seems to be just one more of thousands of' Unidentified Flying Objects for which we have no present explanations because we have laughed such reports out of scientific court. Bachmeier stated to me that, at the time, he felt it had to be some kind of secret device, but, in the ensuing 17 years, we have not heard of any aircraft that can execute instantaneous course-reversal. Vinther's comment to me on a final question I asked as to what he thinks, in general, about the many airline-pilot sightings of unidentified objects over the past 20 years, was: "We're not all having hallucinations." 

Source: Dr. James E. McDonald, Prepared Statement on Unidentified Flying Objects, Page 43-44, Hearings, 1968.