FAR ninety-one dot two oh five and the required equipment list that decides whether your airplane is legal to fly today

FAR 91.205 establishes the minimum instruments and equipment your aircraft must have before it’s legal to fly. Understanding this regulation goes beyond memorizing a mnemonic — it’s the framework for determining whether a broken instrument grounds you or whether you can placard it and go. The answer depends on a decision tree that connects 91.205 to your aircraft’s type certificate and FAR 91.213.

What Does FAR 91.205 Actually Require for VFR Day Flight?

The regulation breaks down into layers. VFR day is the base. VFR night adds to it. IFR stacks on top of both. No layer removes what the previous one required.

The common mnemonic is A TOMATO FLAMES (or ATOMATOFLAMES). Here’s what each letter represents:

• A — Airspeed indicator
• T — Tachometer (one for each engine)
• O — Oil pressure gauge (one per engine)
• M — Manifold pressure gauge (only for constant-speed propeller aircraft — fixed-pitch trainers don’t need one)
• A — Altimeter
• T — Temperature gauge for each liquid-cooled engine (most trainers are air-cooled, so this rarely applies to a Cessna 172 or Piper Cherokee)
• O — Oil temperature gauge (one per engine)
• F — Fuel gauge (one for each tank)
• L — Landing gear position indicator (retractable gear only)
• A — Anti-collision lights (required if certified after March 11, 1996)
• M — Magnetic compass (not the heading indicator — the whiskey compass)
• E — ELT (emergency locator transmitter)
• S — Safety belts (one for each occupant)

The logic behind this list: the FAA is defining the absolute minimum information a pilot needs to safely navigate and operate in visual conditions during daytime. Airspeed to avoid stalls or overspeeds. Altimeter for altitude awareness. Engine instruments for health monitoring. Fuel gauges to prevent fuel exhaustion. A compass for navigation. Safety equipment for emergencies.

What Does VFR Night Add?

The night additions use the mnemonic FLAPS:

• F — Fuses: one spare set or three of each kind
• L — Landing light (only if operated for hire)
• A — Anti-collision lights
• P — Position lights (red, green, and white nav lights)
• S — Source of electrical energy (generator or alternator adequate for installed equipment)

The landing light distinction is important: it’s only required for aircraft operated for hire. Flying yourself and friends to dinner at night in your own aircraft? The regulation doesn’t require a landing light. Flying without one is still a poor decision, but the legal requirement applies only to for-hire operations. Examiners specifically test whether candidates know this distinction.

How Do You Handle an Inoperative Instrument?

This is where 91.205 becomes genuinely practical. The decision tree for a broken instrument has three questions:

1. Is it required by 91.205 for your type of flight (day VFR, night VFR, or IFR)?
2. Is it required by the aircraft’s type certificate or Kinds of Operation Equipment List (KOEL)?
3. Is it required by an airworthiness directive?

If the answer to all three is no, you follow FAR 91.213 paragraph (d): placard the instrument as inoperative (or remove it), make a maintenance record entry, and you’re legal to fly.

Example: Your attitude indicator is completely caged during preflight. For VFR day flight, the attitude indicator is not on the 91.205 list. But you still must verify it isn’t required by your aircraft’s type certificate data sheet or equipment list before departing.

Example: You’re planning a night cross-country and discover dead position lights. Night flight requires position lights under FLAPS. You’re grounded — no exceptions.

Most training aircraft don’t have an FAA-approved Minimum Equipment List (MEL). If yours does, the MEL process replaces 91.213(d) entirely.

What’s the Difference Between “Required” and “Installed”?

Your panel likely has more instruments than 91.205 requires for VFR day. The distinction matters:

• Required instruments (per 91.205, type certificate, or AD): must be working or you don’t fly
• Installed but not required instruments: if broken, placard inoperative and go

On a checkride, the examiner wants to hear you walk through this logic step by step — not just give a yes or no answer.

Why Fuel Gauges Are a Special Case

The fuel gauge requirement states they must indicate the quantity of fuel in each tank. However, the only calibration point the FAA requires is that gauges read zero when the tank is empty. Fuel gauges in light aircraft are notoriously unreliable at other readings.

This is precisely why competent pilots verify fuel quantity visually during preflight and never rely solely on gauges. The regulation sets a legal minimum; good airmanship demands more.

How Regulations Cross-Reference Each Other

An expired ELT battery illustrates how regulations interconnect. While 91.205 lists the ELT as required, FAR 91.207 governs ELT requirements specifically and contains its own exceptions. Knowing a single regulation in isolation isn’t enough — understanding how they reference each other is what separates rote memorization from real knowledge.

Key Takeaways

• 91.205 works in layers: VFR day is the base, night adds FLAPS, IFR stacks further requirements on top
• A broken instrument doesn’t automatically ground you — walk through the three-question decision tree (91.205, type certificate, airworthiness directives)
• Know 91.213(d): for aircraft without an MEL, this paragraph governs how to handle inoperative equipment
• “Required” vs. “installed” is a critical distinction that determines whether a malfunction is a no-go or a placard-and-fly situation
• The regulation sets minimums — sound judgment and good airmanship always go beyond what’s legally required