Allison Division of General Motors delivered first Allison Convair re-engined with Model 501 turboprops in 1960. Subsequently designated Convair 580, deliveries continued until in 1969 programme was passed to Pacific Airmotive. Resumed 1984 as stretched Turbo Flagship ATF580S, plus conversions of Beech Bonanza and T-34 Mentor with Allison 250 turboprop.