During his time as Dan-Air's associate director in charge of the airline's operations, Errol Cossey oversaw the successful introduction of new jet aircraft types into Dan-Air's fleet, beginning with the de Havilland Comet series 4 in 1966 and continuing with the BAC One-Eleven 400 series in 1969, the Boeing 707-320 "Intercontinental" in 1971, the Boeing 727-100 in 1973 as well as the BAC One-Eleven 500 in 1975. He assumed control over the charter fleet, numbering 28 aircraft during the mid-1970s. At that time, Intasun contracted a growing share of its business to Dan-Air. Intasun, like Dan-Air at that time, was shunned by doubtful writers as 'no frills'. It was mainly competing on price with the other tour operators, notably market leader Thomson Holidays.