KEY POINTS:
US space pioneer Wally Schirra, 84, was one of the original Mercury 7 astronauts who flew Nasa's first flights. He was the only astronaut to fly on Mercury, Gemini and Apollo missions.
His Apollo 7 mission in October 1968 was a 10-day test flight for procedures and equipment used on later flights to the Moon. Schirra was a Navy test pilot when he joined Nasa in 1959.
