ELT Inspection Requirements: 91.207 Guide

The short answer is that an emergency locator transmitter covered by 14 CFR 91.207 must be inspected within the preceding 12 calendar months. That date is only one part of the rule. The battery has separate replacement or recharge triggers, and the regulation contains aircraft and operation exceptions that matter before an owner treats any checklist as universal.

This guide explains the recurring items an owner can track. It is not a substitute for the current regulation, the ELT manufacturer's instructions or an appropriately authorised maintenance provider.

The recurring requirements at a glance

Item	Regulatory trigger	What the owner should retain
ELT inspection	Within the preceding 12 calendar months	Maintenance entry identifying the inspection and return-to-service status
Battery replacement or recharge	After more than one cumulative hour of transmitter use	Replacement or recharge entry and updated replacement date
Battery replacement or recharge	When 50% of useful life, or 50% of rechargeable-battery charge life, has expired	Manufacturer life data, replacement date and maintenance entry

“Calendar months” is not the same as 365 days. If the inspection was completed on 8 July, for example, the recurring window runs by calendar month rather than expiring exactly 365 days later. The signed maintenance record remains the controlling evidence for the aircraft.

What the 12-month inspection covers

Section 91.207 calls for the ELT to be inspected for:

• proper installation;
• battery corrosion;
• operation of the controls and crash sensor; and
• the presence of a sufficient signal radiated from the antenna.

The FAA's active Advisory Circular 91-44A, Change 1 adds practical inspection guidance and tells maintainers to use it alongside the documentation supplied with the installed ELT. An owner should not turn that list into a do-it-yourself field test: the device instructions, permitted test window, approved test equipment and maintenance privileges still apply.

The battery can become due before the inspection

The annual inspection and the battery status are separate controls. Under 91.207, batteries must be replaced or recharged when either of these conditions is reached:

1. The transmitter has been in use for more than one cumulative hour.
2. Fifty percent of the battery's useful life—or 50% of the useful life of the charge for a rechargeable battery—has expired.

The new expiration date must be legibly marked on the outside of the transmitter. A recent ELT inspection therefore does not by itself establish that the battery will remain current until the next annual inspection.

For a used aircraft, an unexplained battery date or incomplete activation history is a records question worth resolving before flight. For an accidental activation, record the duration as accurately as practicable and have the maintenance status assessed against the installed unit's instructions.

Applicability and exceptions come first

Section 91.207 generally applies to US-registered civil airplanes, but it includes several exceptions. Among them are certain training operations within 50 nautical miles of the airport of departure, some agricultural operations, aircraft equipped to carry no more than one person, and limited periods after a newly acquired airplane is placed in service. The precise language and conditions matter.

The rule also contains controlled pathways for an airplane with an inoperative ELT to be ferried to a place where it can be repaired or replaced, and for some operations after an ELT has been temporarily removed. Those pathways include conditions such as records entries, placarding and time limits. They are not a general permission to continue normal operations with an unserviceable unit.

Before relying on an exception, check the current text of 91.207 and the facts of the planned operation. An aircraft that did not need an ELT for one flight may need it for the next.

A practical owner tracking record

Keep four pieces of information visible in the aircraft's maintenance tracker:

• last ELT inspection month and the signed record location;
• battery replacement or recharge date;
• marked battery expiration date and the manufacturer's life basis; and
• known activation time since the battery was installed or recharged.

That small record prevents the inspection date and battery status from being blurred into one due item. It also gives a maintenance provider a cleaner starting point when the aircraft changes hands or an activation occurs.

Bottom line

The memorable number is 12 calendar months, but ELT compliance is not a single annual date. Owners need to track the inspection, both battery triggers, the external battery marking and any operation-specific exception separately.

If a date, activation history or maintenance entry is uncertain, treat it as an open airworthiness question and resolve it against the current rule, the installed ELT instructions and an appropriately authorised maintenance provider.

Sources

• eCFR: 14 CFR 91.207 — Emergency locator transmitters
• FAA Pilot's Handbook of Aeronautical Knowledge, Chapter 9
• FAA AC 91-44A, Change 1 — ELT operational and maintenance practices