Government and military
The Air Force UFO studies from 1947 to 1969: Sign, Grudge, Blue Book and the Condon study. 116 events, newest first.
SightingsApr 1950
In spring 1950 the crew and passengers of a TWA DC-3 night flight over northern Indiana reported a large orange-red object. Blue Book chief Edward Ruppelt later wrote that the official answer was blast-furnace light reflecting off haze, an explanation the pilots rejected.
Sightings17 Mar 1950
Many residents of Farmington reported large numbers of fast, darting objects on St. Patrick's Day 1950, after scattered reports on the two previous days. Blue Book chief Edward Ruppelt later suggested fragments of a burst Skyhook balloon as the likeliest cause.
Photo: Christopher Nicol, CC BY-SA 3.0
Government27 Dec 1949
The Air Force announced that Project Grudge was closed and released its final report, which attributed saucer reports to misidentification, mild hysteria and hoaxes and recommended cutting the effort back. Grudge continued at a minimal level until Project Blue Book replaced it.
Photo: US Air Force, Public domain
Sightings24 May 1949
A group fishing near the mouth of the Rogue River, including employees of a NACA aeronautical laboratory, reported a round silver object, watched through binoculars, on May 24, 1949. An Air Force OSI report could not rule out an aircraft; the case was later listed in Blue Book Special Report 14.
Photo: Yurivict at English Wikipedia, CC BY-SA 3.0
MilitaryMar 1949
From March to June 1949, soldiers guarding the nuclear weapons storage site at Killeen Base, Camp Hood, reported unexplained moving lights. Army observers tried to triangulate them on 17 March, and Project Blue Book later listed that case as unidentified.
Government11 Feb 1949
The Air Force renamed Project Sign as Project Grudge, a scaled-down successor that treated most reports as misidentifications. Its 1949 report concluded sightings came from misread natural objects, hoaxes or psychological causes.
Photo: US Air Force, Public domain
GovernmentFeb 1949
Air Materiel Command issued Project Sign's final report, 'Unidentified Aerial Objects', which found no proof either way that the objects were real unknown aircraft. An appendix by RAND's James Lipp judged visits from space very improbable.
Photo: US Air Force, Public domain
Military1949
Astronomer J. Allen Hynek reviewed the 237 reports gathered by the Air Force's Project Sign. His final report attributed about a third to astronomical causes such as planets and meteors, about a third more to balloons, rockets, flares or birds, and left about a fifth unidentified.
Photo: US Air Force, Public domain
Government13 Dec 1948
RAND scientist James Lipp answered Brig. Gen. Donald Putt's request with a letter weighing whether flying objects could be spaceships. He judged such visits possible but very improbable, and the letter was printed as Appendix D of the February 1949 Project Sign report.
Photo: Cbl62, CC BY-SA 3.0
Military1 Oct 1948
North Dakota Air National Guard Lt. George Gorman said he chased a small blinking light in his F-51 over Fargo, which outran him and twice seemed to fly at him. Other observers saw a light. Project Sign investigated, and a January 1949 Air Weather Service study concluded it was a lighted balloon.
Photo: USAF, Public domain
GovernmentSep 1948
Project Sign staff drafted a top secret 'Estimate of the Situation' concluding that some saucers were interplanetary craft. According to later Blue Book chief Edward Ruppelt, Chief of Staff Gen. Hoyt Vandenberg rejected it for lack of proof and it was later burned; no copy has surfaced.
Photo: USAF, Public domain
Government1948
In early 1948, Air Force officers from Wright-Patterson asked J. Allen Hynek, director of Ohio State's McMillin Observatory, to help Project Sign find which saucer reports were astronomical. Hynek, then a skeptic, had no role in Grudge but returned as Blue Book's consultant from 1952 to 1969.
Photo: United States Government, Public domain
Military1948
Large plastic Skyhook research balloons, about 100 feet across, were flown in secret for the Navy, unknown to most Air Force pilots. Blue Book chief Edward Ruppelt and the Condon report later cited them as the likely cause of many reports, including Capt. Thomas Mantell's fatal 1948 chase.
Photo: US Navy, Public domain
GovernmentDec 1947
The Air Force's first formal study of flying-saucer reports, run by Air Materiel Command at Wright Field. It ran until early 1949, when Project Grudge replaced it.
Photo: US Air Force, Public domain
Government23 Sep 1947
Lt. Gen. Nathan Twining, head of Air Materiel Command at Wright Field, wrote to Army Air Forces headquarters that the disc reports described something real, not imagined, and urged a classified, prioritized study. That study began months later as Project Sign.
Photo: U.S. Air Force, Public domain
Military8 Jul 1947
Test pilots, officers and a crew of technicians at Muroc air base in California's Mojave Desert reported round, silvery objects on the morning of July 8, 1947. Edward Ruppelt, later head of Project Blue Book, wrote that this was the first sighting to make the Air Force take a deep interest.
Photo: U.S. Navy, Public domain
