Report Summary	"At about 16:30 in the afternoon of 19 July 1952, the attention of Customs Inspector, Sr. Domingo Troncoso, then with the Peruvian Customs Office at Puerto Maldonado on the jungle frontier with Bolivia, was called to a very strange cigar-shaped flying object over the river area. The big dirigible-shaped craft was flying horizontally and fairly low in the sky, passing from right to left from the observer's position. It was leaving a dense trail of thick smoke, vapor, or substance of some kind on its wake. The thick, whitish substance appeared to be emitted from the aft end of the object in flight.That this object was a real, structured, physical machine may be seen from its reflection in the waters of the Madre de Dios river underneath it.It can be clearly seen to be well above the broad-leaved jungle trees along the bank of the river in the forground of the picture. The object was estimated to be over a hundred feet long. Sr. Troncoso obtained a camera and was able to get one good photograph of the cigar-shaped object."[footnote 1] "The following was submitted by Colonel McHenry Hamilton, Jr, USAF, American Air Attache, Lima, Peru. Aside from some comments by the preparing officer, the report consisted of a translation of a newspaper article in a Lima daily. "A "luminous disc" was supposed to have sped over the Puerto Maldonado area of Peru near the Bolivian border at 4:50 p.m. on July 19th [1951], and among those who claimed to have witnessed the passage was a Peruvian school teacher who took a picture of the UFO, an object that was spewing an impressive wake of smoke. A newspaper account read in part: "The colour of the head or nucleus of this disc was an intense orange. The direction was south to north, was visible from 1 to 2 minutes, leaving a thick vaporous trail which floated for more than 15 minutes. The altitude was more or less 2500 to 3000 feet. It was seen in broad daylight. During its passage, the Peruvian Corporation of the Amazon radio went dead and wasn't able to transmit or receive any signals." "The Peruvian Minister of Education later held discussions with American Embassy officials about the UFO report. The school teacher's photograph and an article about the discussion with the Americans was published in the August 15th issue of the Lima newspaper El Comercio. (Reference 94) "The American Intelligence report on the case seems to be incomplete because there is an unexplained reference to more than one photograph. Colonel Hamilton was informed by Peruvian authorities that some falsification had occurred involving "three different photographs taken by three different persons."[footnote 2] "In a letter dated August 10, 1957, Mr. Moseley gave NICAP the following account of the incident: "In Lima I met Senior Pedro Bardi, who is an agricultural engineer. On July 19, 1952, while on a farm in the Madre de Dios section of Peru, he and others saw a saucer. It was about 4.30 p.m. and they were talking to Lima by radio. "Suddenly, according to Bardi, the radio went dead. They looked out the window and saw a round object going by at high speed. (The witnesses included Pedro Arellano, owner of the farm). The object had passed; it was at an estimated 100 meters altitude and was a little smaller than a DC-3, according to Bardi. It made a buzzing sound as it went by." "The object's speed, Moseley explains, was determined by a report that it was seen four minutes later near Porto Maldonado, 120 kilometers distant. This speed was computed at 1117 miles per hour. "The photograph was secured from a customs administrator named Domingo Troncosco, who said he had taken it as the object flew near the port. Though the photo shows a cigar-shaped object instead of the round shape Bardi described, this could possibly have been due to an elongated effect caused by speed. "It seems obvious to me", Moseley told NICAP, "that the photo is genuine. Incidentally, I (strongly doubt) if this particular saucer was anything but earth-made." "Though NICAP has no reason to doubt the picture's authenticity, we are unable to make an accurate analysis without the negative."[footnote 3] "The object traveled from left to right at about airplane speed. When the trail settled to ground it turned out to be a mass of thin fibery threads."[footnote 4]
Hynek Classification	DD / CE-II (power failure)
Original Vallee Classification	Type IVa
Current Vallee Classification	FB2 (angel hair)
Minimum Distance	1 mi?
Object Appearance	Pale deformed cigar with dark spot on nose, emitting a thick trail of whitish smoke, which may have been found later as angel hair. An earlier observation may have shown the object to have a reddish / yellow luminosity.
Photograph shows the entire scene, including the reflection of the object on the river below
Enlargement shows a close-up of the object, including the trail emission point
Object Behavior	Straight flight with trail
Physical Effect	Possible interference with power, possible angel hair
Medical Effect	None
Comments / Conclusion	A fascinating photo, but the various accounts appear to be contradictory. One theory that the object was faked by painting over a real trail seems to be rendered unlikely by the appearance of striations where the trail leaves the object - at least part of the object seems to be within the trail.

Footnotes

1. UFO Photographs Around the World Vol.2 (A.Roberts/W.Stevens..1985), thanks to Victor J.Kean

2. Loren Gross's UFO:s a history, the 1951 booklet pages 34 and 35, courtesy Anders Liljegren

3. UFO Investigator of September 1957 courtesy Anders Liljegren

4. Video: UFO Sightings: The Photographic Evidence Vol 2; Wendelle Stevens