FAR 1.3 — Rules of Construction
FAR 1.3 explains how to read FAA regulations: singular/plural usage, gender-neutral terms, and the meaning of 'shall,' 'may,' and 'includes' in the FARs.
In Plain English
FAR 1.3 is the FAA's instruction manual for reading the rest of the regulations. It tells you how to interpret the words you'll see throughout Title 14 of the CFR. While it isn't an operational rule you'll fly by, understanding it keeps you from misreading a regulation that actually does affect your flying.
Key points:
- Singular and plural are interchangeable. A rule that says 'aircraft' applies whether you have one airplane or several, and vice versa.
- Masculine includes feminine. Gendered language in older regulations applies equally to all pilots.
- 'Shall' is mandatory — it means you must do the thing.
- 'May' is permissive — it grants authority or permission. Phrases like 'no person may' or 'a person may not' mean the action is prohibited: no one is authorized or permitted to do it.
- 'Includes' means 'includes but is not limited to.' A list following 'includes' is illustrative, not exhaustive — other items can still fall under the rule.
Operationally, this matters when you're parsing a regulation on a checkride or in the cockpit and need to know whether something is required, optional, or merely an example.
Regulation Text
14 CFR § 1.3§ 1.3 Rules of construction.
(a) In this chapter, unless the context requires otherwise:
(1) Words importing the singular include the plural;
(2) Words importing the plural include the singular; and
(3) Words importing the masculine gender include the feminine.
(b) In this chapter, the word:
(1)is used in an imperative sense;
(2)is used in a permissive sense to state authority or permission to do the act prescribed, and the words “no person may * * *” or “a person may not * * *” mean that no person is required, authorized, or permitted to do the act prescribed; and
(3)means “includes but is not limited to”.
[Doc. No. 1150, 27 FR 4590, May 15, 1962, as amended by Amdt. 1-10, 31 FR 5055, Mar. 29, 1966; FAA-2023-1275, Amdt. No. 1-78, 89 FR 92483, Nov. 21, 2024]
Oral Exam Questions a DPE Might Ask
Q1When a regulation says 'no person may,' what does that mean?
Per FAR 1.3, 'no person may' means no one is required, authorized, or permitted to do the act described — it's an outright prohibition.
Q2If a regulation uses the word 'shall,' is the action optional or required?
FAR 1.3 states that 'shall' is used in an imperative sense, meaning the action is mandatory and must be performed.
Q3If a FAR says a checklist 'includes' certain items, can other items also be required?
Yes. Under FAR 1.3, the word 'includes' means 'includes but is not limited to,' so the listed items are examples and additional items may apply.
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Related Sections in Part 1