Never a driver likely to make an impression above national level, Prophet, a Midlands motor trader, raced enthusiastically in some serious machinery for more than a decade.
While competing in Formula Junior, he took his Brabham to South Africa late in the 1963 season and raced in the national Grand Prix, also taking sixth place on aggregate in the Rand GP and finishing second in the Libre Rhodesian GP.
David raced in European F2 from 1964 to 1967 with little success, but found more joy in sports cars, particularly with the Lotus 30. In 1968-69, he raced his Ford GT40 and then a Lola T70, before becoming a regular competitor in Formula 5000 in 1970 with a McLaren 10B which he then took to the non-championship 1971 Argentine GP to claim a lucrative fourth place on aggregate after more fancied runners had fallen by the wayside.
He was killed in 1981 when the helicopter in which he was leaving the Silverstone circuit crashed just after take-off.