Doctoral dissertation “Flight Envelopes of an Aircraft in Mars Atmosphere” presents detailed aerodynamics and performances analysis, based on a new conceptual design of the light aircraft for Mars atmosphere, ALPEMA. Such aircraft allows atmospheric dropping (aeroshell concept application), as well as direct take-off from Martian surface. Complex Martian atmosphere demands for simplified yet efficient wing geometry, capable of maximizing Lift-to-Drag ratio. Martian atmospheric pressure, density, temperature and speed of sound variations, demand a scrutinized power plant choice, which gives significant advantages to ALPEMA in the area of power exploitation. Efficient aspect ratio and drag polar lead to optimal flight envelopes as a proof of sustainability of ALPEMA project. Special performances and basic aerodynamics provide boundaries and constraints of the project, in line with similar and comparable approaches. Chosen propeller, topic which had significant attention in this dissertation, allows for ALPEMA to use maximum power capabilities of its engine, described through Vmin and Vmax, which are significant inputs for flight envelope. Flight envelope, as the goal of this entire analysis, provides effective width and profile for a variety of possible missions. ALPEMA’s specific propeller and engine are a certain decisive advantage when observed along comparable projects, together with its flight envelope.