 Powered by the Pratt & Whitney J75, another three Mk.1s were completed, RL-202, RL-203 and RL-204.The lighter and more powerful Orenda Iroquois engine was soon ready for testing, and the first Mk 2 with the Iroquois, RL-206, was ready for taxi testing in preparation for flight and acceptance tests by RCAF pilots by early 1959.