Frontier Airlines MCO Terminal although certain routes may still leave from Terminal A, the majority of Frontier flights are currently operated from Terminal C. Passengers are therefore advised to confirm their flight information beforehand. It is advised that passengers arrive at least two hours prior to domestic flights and three hours prior to international flights in order to allow enough time for security checks and check-in. All things considered, Frontier Airlines passengers at MCO have a far more pleasurable journey thanks to Terminal C's contemporary amenities and layout.