Right Seat Aviation
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Required equipment

What must be aboard by day: ATOMATOFLAMES

Definition

Before a day VFR flight, 14 CFR 91.205(b) lists the instruments and equipment that must be installed and working. Pilots remember it as ATOMATOFLAMES: Airspeed indicator, Tachometer, Oil-pressure gauge, Manifold-pressure gauge, Altimeter, Temperature gauge, Oil-temperature gauge, Fuel-quantity gauge, Landing-gear position indicator, Anticollision lights, Magnetic compass, ELT, and Safety belts. Several of these are only required in certain airplanes — the table's right column, and the explanation below, say exactly when.

Explanation

Most of the list is simple — every airplane always needs an airspeed indicator, an altimeter, and a magnetic compass. The rest are conditional, and this is where students get tripped up: the tachometer, oil-pressure, and temperature gauges are required per engine; the manifold-pressure gauge only on an airplane with a constant-speed propeller; the landing-gear position indicator only if the gear retracts; and the anticollision light system on aircraft certificated after August 11, 1971. The ELT is required on nearly every airplane — the exception a private pilot is most likely to meet is a single-seat airplane, which doesn't need one (a few others exist, such as certain turbojets and training flights within 50 NM of the airport). Safety belts are required for each occupant.

Required by day — ATOMATOFLAMESRequired when
A — Airspeed indicator Always
T — Tachometer Each engine
O — Oil pressure gauge Pressure system
M — Manifold pressure gauge Constant-speed prop
A — Altimeter Always
T — Temperature gauge Liquid-cooled engine
O — Oil temperature gauge Air-cooled engine
F — Fuel quantity gauge Each tank
L — Landing gear position If retractable
A — Anticollision lights Certd. after 8/11/1971
M — Magnetic compass Always
E — ELT Most aircraft
S — Safety belts Each occupant

Why it matters

This is the legal minimum equipment to fly day VFR. Launching without a required item — or with one inoperative and undealt-with — is illegal, and it's the PIC's job to catch it on preflight.
From the Right Seat

I have students point to each ATOMATOFLAMES item in the actual cockpit and on the airplane on an early lesson — turning the word into thirteen real things they can find makes it stick far better than reciting letters.

A DPE might ask

  • What equipment is required for day VFR flight?
  • Which ATOMATOFLAMES items are only required in certain airplanes?
Adding night: FLAPS

Definition

Flying at night requires everything on the day list plus a few more items, remembered as FLAPS: Fuses (one spare set, or circuit breakers), Landing light, Anticollision lights, Position lights, and a Source of electrical energy. These come from 14 CFR 91.205(c).

Explanation

Two of the FLAPS items have a catch worth knowing. The landing light is only required at night when the aircraft is operated for hire — so a rental flown for personal night currency doesn't legally need one, though flying at night without a landing light is a poor idea regardless. The 'source of electrical energy' means an adequate, working alternator or generator system to run the lights and equipment. Position lights — the red left, green right, and white tail navigation lights — plus a spare set of fuses (unless the airplane uses resettable circuit breakers) round out the list.

Add for night — FLAPSRequired when
F — Fuses (one spare set) Or circuit breakers
L — Landing light If operated for hire
A — Anticollision lights Already required by day
P — Position (nav) lights Always at night
S — Source of electrical energy Adequate (alt./generator)

Why it matters

Night VFR stacks extra equipment on top of the day requirements. Knowing the for-hire catch on the landing light — and that position lights and a working charging system are non-negotiable — keeps a night flight legal.
From the Right Seat

On a student's first night flight, walk the exterior lights with them — position, anticollision, landing — and connect each to its FLAPS letter; it makes the mnemonic concrete in the dark.

A DPE might ask

  • What equipment is required for night VFR that isn't required by day?
  • When is a landing light actually required?
Is it legal to launch?

Definition

Two ideas tie the equipment lists together. First, night requirements stack on day requirements — night VFR means the entire 91.205(b) day list plus the 91.205(c) FLAPS additions, not a separate list. Second, these are legal minimums only: the airplane's POH or type certificate can require more, and an airplane with an approved Minimum Equipment List (MEL) follows the MEL instead. And when a required item is inoperative, it's the 91.213 decision you met in the airworthiness lesson — a required 91.205 item can't simply be placarded and deferred the way a non-required item can.

Explanation

Think of it as layers: every flight needs the day list; add FLAPS after sunset. When something on those lists is inoperative, go back to 91.213 — is the item required (by 91.205, the MEL, the KOEL, the type certificate, or an AD)? A required item that's broken is a no-go until it's fixed; only a non-required, non-hazardous item can be deactivated, placarded 'INOPERATIVE,' and left for the flight. That's why a position light or an anticollision light out at night is a real go/no-go, not a maybe.

Day VFR — 91.205(b)

  • ATOMATOFLAMES
  • Airspeed, altimeter, magnetic compass
  • Engine gauges (per engine)
  • ELT & safety belts
  • Anticollision lights (post-1971)

Night adds — 91.205(c)

  • Everything by day, plus FLAPS
  • Fuses / circuit breakers
  • Landing light (if for hire)
  • Position (nav) lights
  • Adequate source of electrical energy

Why it matters

This is exactly the preflight judgment a real pilot makes — a burned-out light, a dead gauge. Knowing whether the item is required for your flight, day or night, is the difference between a legal launch and an illegal one.
Common error

A common trap is assuming position (navigation) lights are always required. They're a night item — 91.205(c) — not on the day-VFR list. By day they're good practice but not legally required; at night they are. (The for-hire catch, by contrast, applies to the landing light.)

Are position (navigation) lights required for a day VFR flight?

Safety

When an item is inoperative on preflight, resist 'it's just a light.' Run the 91.213 check — is it required for THIS flight, day or night? — and if you're unsure, call your mechanic before you fly.

A DPE might ask

  • How do the day and night equipment requirements relate?
  • You find a required item inoperative on preflight — walk me through what you do.
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