This work presents the results of comprehensive loads and aeroelastic analyses for the design of the high altitude, long endurance, solar electric aircraft HAP. To ensure a sophisticated design, a large number of maneuver, gust, gyroscopic and landing loads cases are considered. The structural sizing results in a total primary structural mass of 38.4 kg, which is very low considering the wing span of ~28.0 m. The extreme light-weight construction (wing loading ~ 4.0 kg/m² leads to a highly flexible aircraft, making aeroelastic analyses mandatory. Results of static and dynamic aeroelastic analyses are presented, showing that the resulting design is plausible from an aeroelastic point of view.