Which of the following is NOT a requirement for flying through an ADIZ?

Flying through an Air Defense Identification Zone (ADIZ) involves specific regulations designed to ensure safety and security in controlled airspace. Among these regulations, filing a flight plan, maintaining two-way communications with air traffic control, and using an altitude-reporting transponder are all essential requirements.

Filing a flight plan helps authorities know the intended route, enhances tracking, and contributes to overall airspace management. Maintaining two-way communications is crucial for the effective coordination of air traffic, allowing for real-time updates and instructions. The use of an altitude-reporting transponder allows air traffic control to accurately track the altitude of the aircraft, providing vital information for maintaining safe separation from other aircraft.

In contrast, the use of a flight helmet is not a requirement for flying through an ADIZ. While wearing a flight helmet is common in some aviation operations, especially in military or certain specialized civilian flights, it is not mandated for compliance with ADIZ regulations. Therefore, the correct answer indicates an action that is not required under the specific context of flying through an ADIZ.