Project RAM launched by a 3-stage rocket is to study the communications blackouts that affect spacecraft re-entering the Earth's atmosphere, which are also known as radio blackouts, ionization blackouts, or reentry blackouts, are caused by an envelope of ionized air around the craft, created by the heat from the compression of the atmosphere by the craft. The ionized air interferes with radio signals. For the Mercury, Gemini, and Apollo spacecraft, such communications blackouts lasted for several minutes.
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| RAM project launch cover with Velvatone cachet, postmarked at Wallops Island on April 10, 1964. Project RAM was launched by 3-stage rocket to study the radio communication blackout during re-entry. |
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| RAM project launch cover postmarked at Wallops Island on April 10, 1964. |
