Disclosed is an aircraft, configured to have a wide range of flight speeds, consuming low levels of power for an extended period of time, while supporting a communications platform with an unobstructed downward-looking view. The aircraft includes an extendable slat at the leading edge of the wing, and a reflexed trailing edge. The aircraft comprises a flying wing extending laterally between two ends and a center point. The wing is swept and has a relatively constant chord. The aircraft also includes a power module configured to provide power via a fuel cell. The fuel cell stores liquid hydrogen as fuel, but uses gaseous hydrogen in the fuel cell. A fuel tank heater is used to control the boil-rate of the fuel in the fuel tank. The fuel cell compresses ambient air for an oxidizer, and operates with the fuel and oxidizer at pressures below one atmosphere.