State acceptance tests began on 17 October, using the second prototype, and finished on 30 January 1948. The group of military test pilots concluded that the afterburner was unreliable and the aircraft was difficult to control in roll. Other complaints were focused on the cockpit; it was deemed was too small and lacked sufficient armor and heating or ventilation. They decided that the Yak-19 could not be recommended for service. Rather than modify the aircraft to address these problems, Yakovlev chose to cancel it entirely in favor of designs using the more-powerful () Rolls-Royce Derwent-derived Klimov RD-500, like his Yak-23 and Yak-25 fighters then under development.