# Batteries used in the emergency locator transmitters — Aircraft inspection and test intervals under 14 CFR Part 91

For Batteries used in the emergency locator transmitters, interval is When the transmitter has been in use for more than 1 cumulative hour; or (2) When 50 percent of their useful life (or, for rechargeable batteries, 50 percent of their useful life of charge) has expired; applies to is emergency locator transmitters required by paragraphs (a) and (b) of this section; consequence if lapsed is must be replaced (or recharged, if the batteries are rechargeable); regulation section is § 91.207, verified against its source on 2026-08-06.

- **Inspection or test item:** Batteries used in the emergency locator transmitters _(verified: appears in the quote below)_
- **Interval:** When the transmitter has been in use for more than 1 cumulative hour; or (2) When 50 percent of their useful life (or, for rechargeable batteries, 50 percent of their useful life of charge) has expired _(verified: appears in the quote below)_
- **Applies to:** emergency locator transmitters required by paragraphs (a) and (b) of this section _(verified: appears in the quote below)_
- **Consequence if lapsed:** must be replaced (or recharged, if the batteries are rechargeable) _(verified: appears in the quote below)_
- **Regulation section:** § 91.207 _(verified: appears in the quote below)_

## What the source says

> Batteries used in the emergency locator transmitters required by paragraphs (a) and (b) of this section must be replaced (or recharged, if the batteries are rechargeable)— (1) When the transmitter has been in use for more than 1 cumulative hour; or (2) When 50 percent of their useful life (or, for rechargeable batteries, 50 percent of their useful life of charge) has expired, as established by the transmitter manufacturer under its approval.

## Source

- https://www.ecfr.gov/api/versioner/v1/full/2026-08-01/title-14.xml?part=91&section=91.207

Last verified: 2026-08-06. Review by: 2028-08-05.
Part of [Aircraft inspection and test intervals under 14 CFR Part 91](https://referencesource.org/aircraft-inspection-and-test-intervals/).