Emergency Locator Transmitters

FAR 91.207 Emergency Locator Transmitters

FAR 91.207 explains ELT requirements: when one is required, battery replacement, 12-month inspections, exceptions, and ferry permissions for student pilots.

In Plain English

FAR 91.207 sets the rules for Emergency Locator Transmitters (ELTs) on U.S.-registered civil airplanes. An ELT broadcasts a distress signal after a crash so search and rescue can find you — that's why this rule matters operationally.

Key requirements:

  • ELT required: Most airplanes must have an approved, operable ELT attached. Part 121/125/135 operations require an automatic type; other operations may use an automatic or personal type.
  • Mounting: The ELT must be installed to minimize crash damage, and fixed/deployable automatic types must be mounted as far aft as practicable.
  • Battery replacement: Replace (or recharge) the battery after 1 cumulative hour of use or when 50% of useful life has expired.
  • Inspection: Required every 12 calendar months for proper installation, battery corrosion, controls/crash sensor operation, and antenna signal.
  • Ferry flights: Allowed for newly acquired aircraft or to a repair facility.
  • Exceptions: Includes training within a 50 NM radius of the departure airport, single-occupant aircraft, and aircraft with the ELT temporarily removed (up to 90 days) with proper logbook entry and a cockpit placard reading "ELT not installed."
Regulation Text
14 CFR § 91.207
§ 91.207 Emergency locator transmitters. (a) Except as provided in paragraphs (e) and (f) of this section, no person may operate a U.S.-registered civil airplane unless— (1) There is attached to the airplane an approved automatic type emergency locator transmitter that is in operable condition for the following operations, except that after June 21, 1995, an emergency locator transmitter that meets the requirements of TSO-C91 may not be used for new installations: (i) Those operations governed by the supplemental air carrier and commercial operator rules of parts 121 and 125; (ii) Charter flights governed by the domestic and flag air carrier rules of part 121 of this chapter; and (iii) Operations governed by part 135 of this chapter; or (2) For operations other than those specified in paragraph (a)(1) of this section, there must be attached to the airplane an approved personal type or an approved automatic type emergency locator transmitter that is in operable condition, except that after June 21, 1995, an emergency locator transmitter that meets the requirements of TSO-C91 may not be used for new installations. (b) Each emergency locator transmitter required by paragraph (a) of this section must be attached to the airplane in such a manner that the probability of damage to the transmitter in the event of crash impact is minimized. Fixed and deployable automatic type transmitters must be attached to the airplane as far aft as practicable. (c) 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. (d) Each emergency locator transmitter required by paragraph (a) of this section must be inspected within 12 calendar months after the last inspection for— (1) Proper installation; (2) Battery corrosion; (3) Operation of the controls and crash sensor; and (4) The presence of a sufficient signal radiated from its antenna. (e) Notwithstanding paragraph (a) of this section, a person may— (1) Ferry a newly acquired airplane from the place where possession of it was taken to a place where the emergency locator transmitter is to be installed; and (2) Ferry an airplane with an inoperative emergency locator transmitter from a place where repairs or replacements cannot be made to a place where they can be made. (f) Paragraph (a) of this section does not apply to— (1) Before January 1, 2004, turbojet-powered aircraft; (2) Aircraft while engaged in scheduled flights by scheduled air carriers; (3) Aircraft while engaged in training operations conducted entirely within a 50-nautical mile radius of the airport from which such local flight operations began; (4) Aircraft while engaged in flight operations incident to design and testing; (5) New aircraft while engaged in flight operations incident to their manufacture, preparation, and delivery; (6) Aircraft while engaged in flight operations incident to the aerial application of chemicals and other substances for agricultural purposes; (7) Aircraft certificated by the Administrator for research and development purposes; (8) Aircraft while used for showing compliance with regulations, crew training, exhibition, air racing, or market surveys; (9) Aircraft equipped to carry not more than one person. (10) An aircraft during any period for which the transmitter has been temporarily removed for inspection, repair, modification, or replacement, subject to the following: (i) No person may operate the aircraft unless the aircraft records contain an entry which includes the date of initial removal, the make, model, serial number, and reason for removing the transmitter, and a placard located in view of the pilot to show “ELT not installed.” (ii) No person may operate the aircraft more than 90 days after the ELT is initially removed from the aircraft; and (11) On and after January 1, 2004, aircraft with a maximum payload capacity of more than 18,000 pounds when used in air transportation. [Docket 18334, 54 FR 34304, Aug. 18, 1989, as amended by Amdt. 91-242, 59 FR 32057, June 21, 1994; 59 FR 34578, July 6, 1994; Amdt. 91-265, 65 FR 81319, Dec. 22, 2000; 66 FR 16316, Mar. 23, 2001]
Oral Exam Questions a DPE Might Ask
Q1When does the ELT battery need to be replaced or recharged?
Per FAR 91.207, the battery must be replaced or recharged after the transmitter has been in use for more than 1 cumulative hour, or when 50% of its useful life (or charge) has expired.
Q2Can you legally fly an aircraft with the ELT removed for repair?
Yes. FAR 91.207(f)(10) allows operation for up to 90 days after initial removal, provided the aircraft records document the removal details and a placard reading "ELT not installed" is visible to the pilot.
Q3What inspections does an ELT require, and how often?
FAR 91.207(d) requires an inspection within 12 calendar months of the last one, checking proper installation, battery corrosion, operation of controls and the crash sensor, and that a sufficient signal is radiated from the antenna.
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FAR 91.207 — Emergency Locator Transmitters (ELT)