Fly - offs against the Crusader III 's main competitor demonstrated that the Vought design had a definite advantage in maneuverability .
The Crusader III 's main competitor is the future McDonnell Douglas F - 4 Phantom II .
Fly - offs against the Crusader III 's main competitor , the future McDonnell Douglas F - 4 Phantom II , demonstrated that the Vought design had a definite advantage in maneuverability .