In combat, many aircraft will operate at altitudes as low as 100 feet and at high airspeeds to defeat ground missile radars and avoid sophisticated surface-to-air missiles, anti-aircraft artillery, and enemy fighters.

According to FAA Regulation Part 91.119, you generally cannot fly at 100 feet unless you are in the process of taking off or landing. For fixed-wing aircraft, the minimum safe altitude is 1,000 feet above the highest obstacle in congested areas and 500 feet over non-congested areas. The only exception is over "open water or sparsely populated areas," where you can fly lower as long as you remain at least 500 feet away from any person, vessel, vehicle, or structure. Helicopters have more flexibility and can operate at lower altitudes if they don't pose a danger to people or property on the ground. In 2026, with the rise of commercial drones, there are even stricter rules: drones must generally stay below 400 feet and are often prohibited from flying directly over people. Flying at 100 feet in a standard plane is considered "reckless operation" and can lead to immediate pilot license revocation, as it provides zero margin for error in the event of an engine failure or a sudden obstacle.