Jacques Vallee found the two page memo in 1967 while working with Dr. Allen Hynek’s papers and partially described it in his book Forbidden Science, giving the author of the memo the code name “Pentacle”.




cc: B. D. Thomas

H. C. Cross/A. D. Westerman

L. R. Jackson

W. T. Reid

P. J. Rieppal

V. W. Ellsey/R. J. Lund January 9, 1953


Extra [handwritten]

Mr. Miles E. Goll

Box 9575

Wright-Patterson Air Force Base, Ohio

Attention Capt. Edward J. Ruppelt

Dear Mr. Goll:

This letter concerns a preliminary recommendation to ATIC on future methods of handling the problem of unidentified aerial objects. This recommendation is based on our experience to date in analyzing several thousands of reports on this subject. We regard the recommendation as preliminary because our analysis is not yet complete, and we are not able to document it where we feel it should be supported by facts from the analysis.

We are making this recommendation prematurely because of a CIA-sponsored meeting of a scientific panel, meeting in Washington, D.C., January 14, 15, and 16, 1953, to consider the problem of “flying saucers”. The CIA-sponsored meeting is being held subsequent to a meeting of CIA, ATIC, and our representatives held at ATIC on December 12, 1952. At the December 12 meeting our representatives strongly recommended that a scientific panel not be set up until the results of our analysis of the sighting-reports collected by ATIC were available. Since a meeting of the panel is now definitely scheduled we feel that agreement between Project Stork and ATIC should be reached as to what can and what cannot be discussed at the meeting in Washington on January 14-16 concerning our preliminary recommendation to ATIC.

Experience to date on our study of unidentified flying objects shows that there is a distinct lack of reliable data with which to work. Even the best-documented reports are frequently lacking in critical information that makes it impossible to arrive at a possible identification, i.e. even in a well-documented report there is always an element of doubt about the data, either because the observer had no means of getting the required data, or was not prepared to utilize the means at his disposal. Therefore, we recommend that a controlled experiment be set up by which reliable physical data can be obtained. A tentative preliminary plan by which the experiment could be designed and carried out is discussed in the following paragraphs.

Based on our experience so far, it is expected that certain conclusions will be reached as a result of our analysis which will make obvious the need for an effort to obtain reliable data from competent observers using the [… unreadable…] necessary equipment. Until more reliable data are available, no positive answers to the problem will be possible.

[ Page 2 ]

Mr. Miles E. Goll-2-January 9, 1953

We expect that our analysis will show that certain areas in the United States have had an abnormally high number of reported incidents of unidentified flying objects. Assuming that, from our analysis, several definite areas productive of reports can be selected, we recommend that one or two of theses areas be set up as experimental areas. This area, or areas, should have observation posts with complete visual skywatch, with radar and photographic coverage, plus all other instruments necessary or helpful in obtaining positive and reliable data on everything in the air over the area. A very complete record of the weather should also be kept during the time of the experiment. Coverage should be so complete that any object in the air could be tracked, and information as to its altitude, velocity, size, shape, color, time of day, etc. could be recorded. All balloon releases or known balloon paths, aircraft flights, and flights of rockets in the test area should be known to those in charge of the experiment. Many different types of aerial activity should be secretly and purposefully scheduled within the area.

We recognize that this proposed experiment would amount to a large-scale military maneuver, or operation, and that it would require extensive preparation and fine coordination, plus maximum security. Although it would be a major operation, and expensive, there are many extra benefits to be derived besides the data on unidentified aerial objects.

The question of just what would be accomplished by the proposed experiment occurs. Just how could the problem of these unidentified objects be solved? From this test area, during the time of the experiment, it can be assumed that there would be a steady flow of reports from ordinary civilian observers, in addition to those by military or other official observers. It should be possible by such a controlled experiment to prove the identity of all objects reported, or to determine positively that there were objects present of unknown identity. Any hoaxes under a set-up such as this could almost certainly be exposed, perhaps not publicly, but at least to the military.

In addition, by having resulting data from the controlled experiment, reports for the last five years could be re-evaluated, in the light of similar but positive information. This should make possible reasonably certain conclusions concerning the importance of the problem of “flying saucers”.

Results of an experiment such as described could assist the Air Force to determine how much attention to pay to future situations when, as in the past summer, there were thousands of sightings reported. In the future, then, the Air Force should be able to make positive statements, reassuring to the public, and to the effect that everything is well under control.

Very truly yours,


H. C. Cross