Air Force Project Blue Book Special Report 14 (Hynek's annotated copy)

Read from the scan by GLM-OCR; expect the odd misread word.

3. The radar screen has picked up birds and in one case a flock of ducks. Flight interceptions proved these phenomena.

An explanation of known types of visual sightings are as follows:

1. Present-day jet aircraft, flying at great speeds and high altitudes, are often mistaken for unknown objects by the untrained observer. Sunlight reflections from the polished surfaces of aircraft can be seen plainly even when the aircraft itself is too distant to be visible. The exhaust of jet aircraft emits a trail and often this is seen rather than the aircraft itself.

2. Weather balloons account for a substantial number of sightings. These balloons, sent to altitudes of 40,000 feet and higher, are launched from virtually every airfield in the country. They are made of rubber or polyethylene, swell as they gain altitude, have very good reflective qualities, carry small lights when launched after dark, and can be seen at very high altitudes.

3. In addition to the ordinary weather balloon, huge 90-foot balloons, which sometimes drift from coast to coast, are used for upper air research. These balloons also have a highly reflective surface and are visible at extreme altitudes.

4. Frequently, unusually bright meteors and planets will cause a flurry of reports, sometimes from relatively experienced observers. At certain times of the year, Venus, for instance, is low on the horizon and will appear to change color and move erratically due to hazy atmospheric conditions. Since the stars are charted and most of their characteristics known, many cases are traced to them. Meteors on the other hand are of rapid single-direction movement and are only visible for a few seconds. Meteor activity is more common at certain times of the year than others, and reports of UFO's have shown a tendency to increase during these periods.

5. Some cases arise which, on the basis of information received are of a weird and peculiar nature. The objects display erratic movements and phenomenal speeds. Since maneuvers and speeds of this kind cannot be traced directly to aircraft, balloons, or known astronomical sources, it is believed that they are reflections from objects rather than being objects themselves. For example: suppose we would hold a mirror in hand under a light, causing a reflection on the ceiling. Only a slight, quick movement of the hand would result in erratic movements and phenomenal speeds of the reflected beam. Reflections may be projected to clouds and haze both from the ground and air. Many things which are common to the sky have highly reflective qualities, such as balloons, aircraft, and clouds. Accurate speeds are also difficult to determine due to the inability of the reporter to judge distance, angles, and time

6. Brilliant flashing lights that sometimes appear red and white in color have been reported by observers. This type has been traced to a new lighting system of commercial airlines and military aircraft. Atop the tail section of these aircraft highly reflective red and white flasher type lights have been installed and are many times misinterpreted by the ground observer.