What FM covers Air Assault and Airborne operations?

The publication that covers Air Assault and Airborne operations is FM 3-99. This Field Manual provides comprehensive guidance on the planning, execution, and evaluation of airborne and air assault operations, which are vital components of the U.S. Army's operational capability. FM 3-99 includes details on the techniques and procedures for conducting these operations, ensuring that soldiers are well-trained and prepared for their roles during such missions.

Other choices relate to different aspects of military operations. For instance, FM 3-21.38 addresses air assault operations specifically but is not the overarching manual for both air assault and airborne operations. FM 3-01 focuses on the principles of joint fires and is not specific to airborne tactics. FM 4-25.11 pertains to first aid and medical training rather than operations. Therefore, FM 3-99 stands out as the essential manual encompassing both airborne and air assault operations, making it the correct answer.