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

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

## Source of Reports

The majority of reports of aerial phonomena have come from civilians. About 8 percent come from civil airlines pilots, while approximately 25 percent are reported by military personnel. Reports have been received also from highly qualified scientists. Although primary significance is attached to reports from qualified observers, there is no intention to discredit untrained observers.

The Air Force has received many reports of unusual images on radar scopes. It is fairly well established that some of these images are ground objects reflected from a layer of warm air above the earth (a temperature inversion).

Temperature inversion reflections can give a return on a radar scope that is as sharp as that received from an aircraft. Speed ranges of these returns are reportedly from zero to fantastic spoods. The "objects" also appear to move in all directions.

## Radar Sightings

Such radar sightings have resulted in hundreds of fruitless intercept efforts.

One scientific theory holds that light can be similarly reflected from a layer of warm air above the earth and, if proven to be correct, this could account for some visual sightings.

Bearing out the theory of temporature inversion reflection is an incident which occurred in January 1951 near Oakridgo, Tennossoo. Two Air Force aircraft attempted to intercept an unidentified "object" and actually established a radar "lock" on the object. Their altitude at the time was 7,000 feet. The unidentified object, according to their radar, appeared to be at an elevation of ten to 25 degrees. Three passes were made in an attempt to close on the object. In each instance the pilots reported that their radar led them first upward and then down toward a specific point on the ground.

Ionized clouds are believed to be the cause of some unidentified radar returns. Thundorstorm activity is identifiable by radar, and radar is used for the purpose of avoiding thunderstorms. In addition, radar has picked up many objects first reported as "unidontified phenomena" which were later identified as aircraft, birds, balloons, ice formations in the air, or other known aerial objects or manifestations.

## Policy Regarding Attemptod Interception

No orders have been issued by the Air Defense Command to its fighter units to fire on unidentified aerial phenomena. The Air Defense Command is charged with air defense of the United States, and its mission is to attack anything airborne which is known or appears to be hostile. This should not be intolerated to soon that our pilots will fire haphasardly on anything that flies.

Attempts at interception are not made every time that unidentified images appear briefly on an Air Force radar scope. Current Air Force interceptors are short-range, short-duration, high-speed aircraft and can be employed most effectively when it is possible to track a target by visual or radar means so that its position in the air at some future time may be predicted with a reasonablo degree of accuracy.

## Methods of Evaluating

The first step in evaluating sightings of unusual aerial phenomena is to collect all available data and check it against known airborne objects such as balloons, aircraft, missiles, meteors, and weather phenomena. If still unexplained, reports from reliable sources, with sufficient details, are turned over to specialists in various scientific fields for further analysis.

## Future Plans for Evaluating

As stated earlier, there is a need for better reports from trained observers using adoquate equipment. The Air Force intends to implement its present study with instruments wherever possiblo.

The recent development of special photographic equipment may make it possible to gathor data hitherto unobtainable through ordinary photographic methods. This equipment consists of a diffraction grating camera which separates light into its component parts (spectrum) and registers them on film. The principle involved is that used by astronomers in determining the composition of the stars. In this manner Air Force scientists may be able to detormino the characteristics of the phenomena and subsequently identify the source.

Another proposal involves the use of a continuously operating Schmidt telescope equipped with a camera. This telescope has a wide aperture lons and is capable of covering a cone of 150 degrees or nearly the whole sky from horizon to horizon. This equipment will make it possible to get on a series of photographic plates a complete record of what happens in the sky at night.

## What "Saucers" Are Not

The Air Force has stated in the past, and roaffirms at the present time, that those unidontified aerial phenomena are not a secret weapon, missile or aircraft, developed by the United States. None of the three military departments nor any other agency in the government is conducting experiments, classified or otherwise, with flying objects which could be a basis for the reported phenomena. As far as is known there is nothing in them that is associated with material or vehicles that are directed against the United States, from another country or from other planets.

Your intorost in this matter is greatly appreciated. Ploaso call upon us if we may be of further service.

Sinceroly yours,