FAA Ground School Practice Test

How often should an emergency locator transmitter (ELT) battery be replaced?

1. Every year

2. Every 24 months

3. Every 48 months

4. Every 60 months

The correct answer is: Every 48 months

The recommended replacement interval for an emergency locator transmitter (ELT) battery is every 48 months. This guideline is based on the operational requirement to ensure reliability when the transmitter is activated in an emergency situation. The purpose of the ELT is to facilitate search and rescue operations by emitting a distress signal, and having a battery that is fresh and fully functional is critical to its effectiveness. Routine inspections, maintenance, and battery replacements are important to ensure the ELT will operate when needed. The 48-month timeframe allows for the natural degradation that can occur in batteries over time, especially when subject to temperature variations and cycles of use. This ensures that the device will maintain its reliability and readiness, aligning with the standards set forth by regulatory bodies. In contrast, intervals shorter or longer than 48 months—such as annually, every 24 months, or every 60 months—might increase the risk of a dead battery during an actual emergency, which could hinder rescue efforts. Therefore, adhering to the 48-month replacement schedule is necessary for the maintenance of safety standards for aircraft operations.