H. Marshall Chadwell

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H. Marshall Chadwell

Illustration of official papers and files — Illustration: official papers and files. An artist's impression drawn for this site, not a photograph of the event.

Type	Person
Also known as	Chadwell
On the Timeline	1 event, 1952

H. Marshall Chadwell was assistant director of the CIA's Office of Scientific Intelligence (OSI) in the early 1950s.

The CIA and UFOs

Howard P. Robertson: Luis W. Alvarez — Howard P. Robertson: Luis W. Alvarez Photo: Donald Cooksey / Lawrence Berkeley National Laboratory (per [3] · Public domain · via Wikimedia Commons

After the summer 1952 wave of sightings, including the Washington, D.C., radar cases, Chadwell warned CIA Director Walter Bedell Smith that UFOs might pose national security problems, such as clogging warning systems during an attack or causing panic. In December 1952 he and colleague P.G. Strong met MIT leaders, including provost Julius Stratton, about a scientific review. Chadwell then organised the panel of scientists led by Howard P. Robertson that met in January 1953. Its recommendations to reduce public interest in UFOs shaped government policy for years.

On the UAP Timeline

Illustration of an observer watching the sky — Illustration: an observer watching the sky. An artist's impression drawn for this site, not a photograph of the event.

CIA–MIT talks on UFO study (1952) (2 December 1952) — A CIA science chief meets MIT leaders about studying UAP through Project Lincoln.

Connected articles

References

'Flying Saucers' memo, 3 Dec 1952 — CIA reading room · cia.gov · archived copy
CIA Intelligence Advisory Committee minutes, 4 Dec 1952 (PDF) · archive.org · archived copy
Strong memo text (PDF) — Internet Archive CIA UFO collection · archive.org · archived copy
Chadwell memo to the DCI, 2 Dec 1952 — Patrick Gross · ufology.patrickgross.org · archived copy
Chadwell letter to Julius Stratton, Jan 1953 — UFO Scans · ufoscans.com · archived copy

Categories: Central intelligence agency | Julius stratton | P g strong | Person | Unidentified anomalous phenomena

This page was last edited on 29 October 2026. Articles are written in our own words from the sources listed under References; disputed claims are attributed to the people who made them.

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