Early Statistical Analysis of UFO Sightings

In late 1952 the Air Force, and others, put together a report that addressed assessment of the success of the current witness form, tabulation of results of MANY reports from 1947-1952 (at the time of the reports writing it was noted 1947 cases had not been turned over for analysis).

The results are interesting:
Most sightings (69.5%) occurred through open space or binoculars (12.6%) when skies were clear (74.8%), had scattered clouds (16.2), no wind (51.8%) or only a slight breeze (34.6%). Environment was dry (81%) and warm (52.6%) or cool (17.7%). Most sightings lasted 1 second to 10 seconds (25.6%), over ten minutes (19.1%), 11 seconds to 30 seconds (15.5%) or 2 minutes to 5 minutes (12.5%).
Witnesses had a certainty level of these facts ranging from certain (49.4%) to fairly certain (40.8%),
Witnesses stated the objects seen looked solid a majority of the time (78.5%).

Witnesses reported the objects viewed changed direction (39.6%), speed (14.9%), color (11.9%) and flickered (17.7%). Conversely a majority  said object did bit change direction (54.5%), a majority said the object did not change size (75.1%), a majority (79.3) said object did not change color. As for giving off some light 72,3% said yes while only 22.3% said no.

Light and Sound responses indicated 89.9% said the object observed made no sound.

As to the color objects observed the most common were silver, pink, orange, green, grey, yellow, white-bluish-white, green-blue, dark, red, unclassified, no response.   White (Blue-white) was reported most (24.2%), followed by silver (16.2%),yellow (14.9%) and orange (13.0%).

When responding to the question of how many objects a witness had seen the responses were based on the 30.9% who replied they had seen more than one object.  Most witnesses seeing more than one say 2 (38.5%), 3 (19.2%) or 5 (17.6%).   Most objects observed did not move behind anything (64.9%) and most did not move in front of something (76.8%).

Gauging size would be a consistent issue because developers of the examination form did not adopt standardized frames of reference. It is assumed from some statements throughout the Project Blue Book reports that the standard reference had an implied "when held at arm's length" aspect.  Astronomers such as Dr. J. Allen Hynek pointed out the handy tool of the field: a dime held at arms length generally covers the moon in the sky and provides some visual comparison data.  The problem was that investigators sometimes refused to accept the size estimations, even from well trained and qualified witnesses.

Size comparisons ranged from pea (19.1%), baseball (12.5%), basketball (13.7%), bike wheel (7.7%), dirigible (6.6 %) large aircraft (4.2%) and an auto (2.5%). Certainty levels for this section ranged from certain (47.6%) to fairly certain (35.1%).

Height above the earth was most often a Don't Know (28.2%), 10,000 feet plus (25.8%) and 1001 to 5000 feet (17.9%).

When the object - whatever it was- left the viewing field it usually did so Suddenly (52.8%) and next just gradually (40.1%).

Finally, for the people reporting these odd occurrences the majority (91.6%) had never seen such a thing before and but had one or more people with them at the time of the sighting.
most (75.6%) were not alone