65 HS1-834228961 62-HQ-83894 Serial 164

This FBI file serial from case 62-HQ-83894 holds several copies of Air Intelligence Requirements Memorandum Number 4, "Unconventional Aircraft." Major General C. P. Cabell, Director of Intelligence at Headquarters United States Air Force, issued the memorandum on 15 February 1949. It sets continuing Air Force requirements for information on unidentified flying objects, including "Flying Discs," and tells commands to send reports to Air Materiel Command at Wright-Patterson AFB. It also includes a detailed checklist covering sighting details, observers, radar data and physical evidence, and the FBI Director appears on its distribution list.

From the source:Release of 2026-05-08 Incident: N/A, N/A. The FBI's 62-HQ-83894 case file includes investigative records, eyewitness testimonies, and public reports concerning Unidentified Flying Objects and flying discs documented between June 1947 and July 1968. The records include high-profile incident accounts, photographic evidence from sites like Oak Ridge, TN, and technical proposals regarding potential propulsion systems. Additional topics include convention programs, researcher accounts, and extensive media coverage from the period. This file is partially posted on FBI vault with more redactions and some pages missing. Included here is the complete case file with several newly declassified pages and only minor redactions.

RESTRICTED
17. Alr ducts.
a. Slots.
b. Duct openlngs.
18. Speed - M.P.H.
19. Sound.
a. Continuous whlne or buzz.
b. Roar, whlstle, wl;loosh.
c. Intermittent.
20. Manner of disappearance.
a. Explode.
(1) PosslbHlty of fragments.
(2) Other physical evidence.
b. Faded from view.
c . Disappeared behind obstacle.
Relative to the Observer
1. Name of observer.
2. Address.
3. Occupation.
4. Place of business.
a . Employer or employee.
5. Pertinent hobbies.
a. Is observer amateur astronomer, pilot, engineer, etc.
b. Length of time engaged ln hobby (experience).
6. Ablllty to determine:
a . Color.
b. Speed of moving objects.
c. Size at distance.
7. Rell.abllity of observer.
a. Sources.
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