|The rescue of Roger Mallinson and Roger Chapman occurred between 29 August and 1 September 1973 after their Vickers Oceanics small submersible Pisces III was trapped on the seabed at a depth of 1,575 ft (480 m), 150 mi (240 km) off Ireland in the Irish Sea. The 76-hour multinational rescue effort resulted in the deepest sub rescue in history.|
2. British Post Office commemorative cover. 21 JUN
Signed by Mallinson and Chapman.
|CANTAT 2. British Post Office
21 JUN 1974.