FAR 91.531 — Second in Command Requirements
FAR 91.531 explains when a second in command pilot is required, including type-certificated, large, and commuter airplanes, plus SIC qualification rules.
In Plain English
FAR 91.531 tells you when an airplane must be flown with a second in command (SIC) — a copilot — and the qualifications that SIC must hold.
Unless an exception applies, you may not operate the following airplanes without an SIC:
- Any airplane type certificated for more than one required pilot
- Any large airplane (over 12,500 lbs max takeoff weight)
- Any commuter category airplane
You don't need an SIC if:
- The airplane is certificated for single-pilot operation, or
- It's a large or turbojet multiengine airplane with a special airworthiness certificate that was either originally designed with only one pilot station, or originally had more than one station but single-pilot ops are allowed by the AFM or a branch of the U.S. or foreign military.
When an SIC is required, that pilot must meet the qualifications in FAR 61.55 (familiarity with the aircraft and recent SIC training/checks). This rule matters operationally because flying a two-pilot airplane single-pilot — or with an unqualified copilot — is a regulatory violation, even if you're rated in the airplane.
Regulation Text
14 CFR § 91.531§ 91.531 Second in command requirements.
(a) Except as provided in paragraph (b) of this section, no person may operate the following airplanes without a pilot designated as second in command:
(1) Any airplane that is type certificated for more than one required pilot.
(2) Any large airplane.
(3) Any commuter category airplane.
(b) A person may operate the following airplanes without a pilot designated as second in command:
(1) Any airplane certificated for operation with one pilot.
(2) A large airplane or turbojet-powered multiengine airplane that holds a special airworthiness certificate, if:
(i) The airplane was originally designed with only one pilot station; or
(ii) The airplane was originally designed with more than one pilot station, but single pilot operations were permitted by the airplane flight manual or were otherwise permitted by a branch of the United States Armed Forces or the armed forces of a foreign contracting State to the Convention on International Civil Aviation.
(c) No person may designate a pilot to serve as second in command, nor may any pilot serve as second in command, of an airplane required under this section to have two pilots unless that pilot meets the qualifications for second in command prescribed in § 61.55 of this chapter.
[Docket FAA-2016-6142, Amdt. 91-351, 83 FR 30282, June 27, 2018]
Oral Exam Questions a DPE Might Ask
Q1When does FAR 91.531 require a second in command on board?
Per FAR 91.531(a), an SIC is required for any airplane type certificated for more than one required pilot, any large airplane, or any commuter category airplane.
Q2Are there any exceptions that let you fly a large or turbojet multiengine airplane single-pilot?
Yes. FAR 91.531(b) allows single-pilot operation of a large or turbojet multiengine airplane with a special airworthiness certificate if it was originally designed with only one pilot station, or if single-pilot ops are permitted by the AFM or a U.S. or foreign military branch.
Q3What qualifications must a pilot meet to serve as second in command under this rule?
FAR 91.531(c) requires that any pilot serving as SIC in an airplane that requires two pilots must meet the SIC qualification requirements of FAR 61.55.
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Related Sections in Part 91