This letter's recommendations led to the creation of Project Sign, the US military's first serious UFO investigation project.
23 September 1947
SUBJECT: AMC Opinion Concerning "Flying Discs"
TO: Commanding General
Army Air Forces
Washington 25, D.C.
ATTENTION: Brig. General George Schulgen
1. As requested by AC/AS-2 there is presented below the considered
opinion of this command concerning the so-called "Flying Discs." This
opinion is based on interrogation report data furnished by AC/AS-2 and
preliminary studies by personnel of T-2 and Aircraft Laboratory,
Engineering Division T-3. This opinion was arrived at in a conference
between personnel from the Air Institute of Technology, Intelligence T-2,
Office, Chief of Engineering Division, and the Aircraft, Power Plant and
Propeller Laboratories of Engineering Division T-3.
2. It is the opinion that:
a. The phenomenon reported is something real and not visionary or
b. There are objects probably approximately the shape of a disc, of such
appreciable size as to appear to be as large as man-made aircraft.
c. There is the possibility that some of the incidents may be caused
by natural phenomena, such as meteors.
d. The reported operating characteristics such as extreme rates of
climb, manoeuvrability (particularly in roll), and action which must
be considered evasive when sighted or contacted by friendly aircraft
and radar, lend belief to the possibility that some of the objects
are controlled either manually, automatically or remotely.
e. The apparent common description of the objects is as follows:
(1) Metallic or light reflecting surface.
(2) Absence of trail, except in a few instances when the object
apparently was operating under high performance conditions.
(3) Circular or elliptical in shape, flat on bottom and domed on
(4) Several reports of well kept formation flights varying from
three to nine objects.
(5) Normally no associated sound, except in three instances a
substantial rumbling roar was noted.
(6) Level flight speeds normally about 300 knots are estimated.
f. It is possible within the present U.S. knowledge - provided
extensive detailed development is undertaken - to construct a
piloted aircraft which has the general description of the object in
subparagraph (e) above which would be capable of an approximate
range of 700 miles at subsonic speeds.
g. Any developments in this country along the lines indicated would be
extremely expensive, time consuming and at the considerable expense
of current projects and therefore, if directed, should be set up
independently of existing projects.
h. Due consideration must be given the following:
(1) The possibility that these objects are of domestic origin
-the product of some high security project not known to
AC/AS-2 or this command.
(2) The lack of physical evidence in the shape of crash
recovered exhibits which would undeniably prove the
existence of these objects.
(3) The possibility that some foreign nation has a form of
propulsion possibly nuclear, which is outside of our
3. It is recommended that:
a. Headquarters, Army Air Forces issue a directive assigning a
priority, security classification and code name for a detailed
study of this matter to include the preparation of complete sets of
all available and pertinent data which will then be made available
to the Army , Navy, Atomic Energy Commission, JRDB, the Air Force
Scientific Advisory Group, NACA, and the RAND and NEPA projects
for comments and recommendations, with a preliminary report to be
forwarded within 15 days of receipt of the data and a detailed
report thereafter every 30 days as the investigation develops. A
complete interchange of data should be effected.
4. Awaiting a specific directive AMC will continue the investigation
within its current resources in order to more closely define the
nature of the phenomenon. Detailed Essential Elements of Information
will be formulated immediately for transmittal thru channels.
Lieutenant General, U.S.A.