A method and apparatus are provided for nulling a radio frequency (RF) beam for a high-altitude platform (HAP). A transmitter generates an RF signal. A primary antenna system generates an RF beam based on the RF signal. One or more processors determine a result indicating whether to modify the RF beam. When the result indicates to modify the RF beam, a detachable nulling subassembly generates nulling signals based on the RF signal to modify the RF beam generated by the primary antenna system.