Rules of Construction

How the FAA Tells You to Read Its Own Regs

This is the most under-read regulation in the FARs. Three short paragraphs sitting at the very front of 14 CFR Part 1, and almost nobody cites them on a checkride. But here's the catch — § 1.3 is the legal grammar rulebook for every other reg you'll ever touch. If you don't know what "shall" and "may" mean in FAA language, you don't actually know what § 91.103, § 91.205, or § 61.57 require of you. You're guessing.

The FAA wrote § 1.3 so they wouldn't have to define these terms inside every reg. Read it once, and the entire FAR/AIM becomes easier to parse.

Here are the words that matter:

Practical example. § 91.103 opens with "Each pilot in command shall, before beginning a flight, become familiar with all available information concerning that flight." That's imperative. You don't get to skip it on a short hop. Compare that to § 91.3(b): the PIC "may deviate from any rule of this part" in an in-flight emergency. That's permissive — the authority is granted, but you decide whether to use it.

The paragraph (a) rules — singular includes plural, masculine includes feminine — sound trivial, but they're why the FAA can write "aircraft" once and have it cover one airplane or a whole fleet. It's drafting economy, not a legal trap.

Lawyers know § 1.3 cold. Examiners know it. Most pilots have never read it. That's a gap worth closing.

What an Examiner Asks About § 1.3

DPEs occasionally test this on Commercial and CFI rides — especially CFI initial, where regulatory literacy is the whole game. Expect questions like:

• "What's the legal difference between shall and may in the FARs?"
• "When a reg says no person may, what does that mean?"
• "Does includes mean the list that follows is the complete list?"
• "What happens if a reg uses the word should?" (Trick question. Should is not defined in § 1.3. The FAA uses it for recommended or best-practice language — not mandatory. If you see should, it's guidance, not a rule.)

If you can answer these four cleanly, you've shown the examiner you don't just memorize regs — you understand how to read them.

Reading § 91.103 Through the § 1.3 Lens

Let's run § 91.103(b)(1) through the decoder. It says: "For civil aircraft for which an approved Airplane or Rotorcraft Flight Manual containing takeoff and landing distance data is required, the takeoff and landing distance data contained therein."

Why "is required" and not "is present" or "is on board"? Because the operative legal trigger is the FAA requirement, not whether the book is physically sitting in the seat pocket. If your aircraft doesn't require an approved AFM — some experimental categories, certain older type certificates — then (b)(1) doesn't apply to you and you fall through to (b)(2)'s general takeoff/landing data requirement. Without § 1.3's reading framework, you might assume "approved AFM" means "AFM in the cockpit," and you'd be wrong about who the rule applies to.

The same logic runs through every reg you'll touch. § 91.205 lists required equipment with "no person may operate" — that's a flat prohibition unless the equipment is on board and working. § 91.213 uses "may" repeatedly when describing MEL relief — that's permission granted, but only if the conditions are met. Every one of those words means something specific because § 1.3 said so.

Read § 1.3 first. Every other reg gets clearer.