Legal Interpretations
Klaus 2015
Summary
The Question
Under 14 CFR 91.609(e), is a cockpit voice recorder required when the pilot in command chooses to fly with two pilots though only one is required?
Background
A requester asked what "operating rule" means in the CVR requirement for multi-engine, turbine-powered aircraft with six or more passenger seats for which two pilots are required by type certification or operating rule.
The FAA’s Interpretation
No. The FAA considers an operating rule to be any 14 CFR regulation applicable to a particular flight; if another applicable regulation requires a second pilot under certain conditions, such as IFR, a CVR is required when flying with two pilots in those conditions. An operator's choice to use two pilots when only one is required does not require a CVR under 14 CFR 91.609(e).
- Requester
- Klaus
- Issued
- June 15, 2015
- Subject
- General Operating & Flight Rules
Regulations Cited
Page 1
U.S. Department
of Transportation
Federal Aviation
Administration
JUN. 1.5 2015
Mark Klaus
Dear Mr. Klaus:
On July 8, 2014, you requested an interpretation of the cockpit voice recorder (CVR) requirements of §91.609 of Title 14 of the Code of Federal Regulations (CFR). Your question concerns the language in §91.609 regarding the need for the equipment when two pilots are required.
Section 91.609(e) addresses cockpit voice recorders and states:
Unless otherwise authorized by the Administrator, after October 11. 1991, no person may operate a U.S. civil registered multi-engine, turbine powered airplane or rotorcraft having a passenger seating configuration of six passengers or more and for which two pilots are required by type certification or operating rule unless it is equipped with an approved cockpit voice recorder that: (the equipment requirements follow).
In this context, you are requesting "the definition of "operating mle.>'" You go on to ask whether the section means "when two pilots are requiied for the flight or used by the choice of the pilot-in-command."
Although it is not defined in pait 1> the Federal Aviation Administration considers an operating rule to be any regulation in Title 14 that is applicable to a particular flight. It would be impossible for us to state what regulations apply to a paiticular flight without knowing most of the circumstances of a particular operation, the aircraft being used, and the status of the operator. As but one example, if the type certificate data sheet (TCDS) for an aircraft indicates that only one pilot is necessary, but another applicable regulation requires a second pilot under certain conditions (such as instrument flight rules), a CVR would be required when flying with two pilots in those conditions. The phrase in the regulation "when two pilots are required by .. . operating rule" only refers to applicable operating rules. The choice of an operator to use two pilots when only one is required (after consideration of all applicable certification and operating rules) does not require that a CVR be installed and operated to meet§ 91.609(e).
Page 2
This interpretation was prepared by Karen Petronis, Senior Attorney for Regulations in my office. It was coordinated with the Avionics Maintenance Branch, AFS-360 and the Air Transportation Division, AFS-200 of the Flight Standards Service. If you have further questions about this interpretation please contact my staff at 202-267-3073.
Sincerely,
Lorelei Peter
Deputy Assistant Chief Counsel for Regulations
Regulations Referenced
Snapshot retrieved August 6, 2026.