FAR Ninety-One Point Two Thirteen, the Inoperative Equipment Question That Grounds More Pilots Than It Should, and the Four-Step Decision That Tells You Whether That Broken Gauge Changes Your Preflight

FAR 91.213 gives you a structured, four-question decision process for inoperative equipment. Work through each question in order - if you answer yes to any one of them, the aircraft does not fly until the item is repaired. Only if you work through all four and answer no to each do you have a legal path to continue.

What Is FAR 91.213 and Why Does It Matter?

Most pilots have either memorized a flowchart without really understanding it, or they know just enough to be confused when something actually breaks. This regulation is not a list of things you can get away with. It is a framework for making a sound airworthiness decision before you ever leave the ground - one that protects you and every pilot who flies that aircraft after you.

Step 1: Does the Aircraft Have an Approved Minimum Equipment List?

A Minimum Equipment List (MEL) is an FAA-approved document specifying which items can be inoperative and under what conditions an aircraft may still be legally operated. Airlines, charter operators, and some flight schools operate under approved MELs. If your aircraft has one, it becomes the governing document for every inoperative equipment decision - you look up the item, follow the deferral conditions exactly, and apply any required operational limitations.

The practical reality: most general aviation training aircraft operated under FAR Part 91 do not have an approved MEL. For most student pilots and private pilots flying a Cessna 172 or Piper Cherokee, the answer to Step 1 is no. Move to Step 2.

Step 2: Is the Inoperative Item Required for This Flight?

This is where you need to know your required equipment lists cold. The answer depends on the type of operation you are planning, and you must check four sources: the applicable regulation list, any airworthiness directives, the POH, and the type certificate data sheet.

FAR 91.205 specifies the required instruments and equipment by operation type.

VFR Day: TOMATO FLAMES

For daytime visual flight rules operations, the required equipment is taught with the mnemonic TOMATO FLAMES:

• T - Tachometer (each engine)
• O - Oil pressure gauge (each engine using pressure lubrication)
• M - Manifold pressure gauge (altitude engines only)
• A - Altimeter
• T - Temperature gauge (each liquid-cooled engine)
• O - Oil temperature gauge (air-cooled engines)
• F - Fuel gauge (each tank)
• L - Landing gear position indicator (retractable gear only)
• A - Airspeed indicator
• M - Magnetic compass
• E - Emergency locator transmitter (ELT), per FAR 91.207
• S - Safety belts (all occupants)

If the broken item is on this list and applies to your aircraft, the aircraft is not airworthy for that VFR day flight.

VFR Night: TOMATO FLAMES Plus FLAPS

Night operations require everything in TOMATO FLAMES plus the items in FLAPS:

• F - Fuses (one complete spare set, or three spares of each type required)
• L - Landing light (if operated for hire)
• A - Anti-collision lights
• P - Position lights
• S - Source of electrical energy adequate for all installed equipment

IFR: GRABCARD

Instrument flight rules operations require an additional set of equipment, taught as GRABCARD:

• G - Generator or alternator
• R - Radios appropriate for the route and operation
• A - Altimeter (sensitive)
• B - Ball (slip-skid indicator)
• C - Clock (sweep second hand or digital, showing hours, minutes, and seconds)
• A - Attitude indicator
• R - Rate-of-turn indicator
• D - Directional gyro (heading indicator)

Every item in GRABCARD must be functioning before you file IFR.

Also Check ADs and the POH

Beyond the regulation lists, check two additional sources. First, any applicable airworthiness directives (ADs) - mandatory FAA safety orders against specific aircraft, components, or systems. If an AD has made a piece of equipment mandatory, that item is required regardless of whether it appears in the standard lists. Second, check the aircraft’s Pilot’s Operating Handbook (POH). Some manufacturers have included specific items in the required equipment section as a condition of the type certificate. If it is listed there, it is required.

If the broken item does not appear in any of these sources for the operation you are planning, move to Step 3.

Step 3: Does the Inoperative Equipment Present a Hazard?

This is where the regulation asks you to exercise real pilot-in-command judgment. Some items are not legally required but their absence makes a specific flight genuinely dangerous depending on the circumstances.

A broken cabin heater does not appear on any required equipment list. But a two-hour flight over mountains in November through passes with no emergency landing options is a different situation than a local summer pattern. A broken door seal may not be on any list, but at altitude in winter it can become a serious problem quickly. The question is not only whether you are required to have this item - the question is whether this flight is genuinely safe without it.

This question draws directly on FAR 91.3, which places final authority for the safety of a flight on the pilot in command. If your honest answer is yes, it presents a hazard for this specific flight, the aircraft stays on the ground. If your honest answer is no, proceed to Step 4.

Step 4: Deactivate the Item and Placard It as Inoperative

FAR 91.213 requires that the inoperative instrument or equipment be either deactivated by an appropriately certificated maintenance person, or placarded as inoperative in a conspicuous location near the item.

Both parts matter. The placard is not bureaucratic paperwork - it is a communication to the next pilot, the next student, the next renter. It says: this item is known inoperative and the aircraft has been released in that condition. Without the placard, the next person who climbs in has no way to know whether the item failed during the previous flight or was broken going in. That distinction matters for safety, for aircraft records, and for accident investigation.

Whether an item requires physical deactivation by a mechanic or whether a placard alone is sufficient depends on the item and the risks it poses. An instrument that provides wrong data rather than no data may need to be physically disabled, not just labeled - misleading information from a failed instrument can be more dangerous than a blank one. When in doubt, your maintenance shop makes that call, not you.

How Does This Apply in Real Scenarios?

Scenario 1: VSI pegged at the wrong reading on a VFR day flight. The vertical speed indicator (VSI) is not in TOMATO FLAMES, not referenced in any applicable airworthiness directive, and not in the required equipment section of the POH for most training aircraft. For a local VFR day flight, it does not present a hazard. Result: placard it and go. The VSI is a useful instrument, but it is not required for visual flight operations.

Scenario 2: Altimeter reading 300 feet high after setting the current altimeter setting. For IFR operations, the altimeter is in GRABCARD - required, full stop. But even for a VFR flight, an altimeter reading 300 feet off is a safety hazard regardless of what the regulation lists say. That aircraft does not fly. It needs a maintenance inspection first.

Scenario 3: Left position light inoperative discovered during a night flight walkaround. Position lights are required for VFR night operations. If the flight takes place at night, the aircraft is not airworthy without it. If the flight is entirely in daylight, the light is not required for that specific operation - but placard it, and think carefully about whether the flight could realistically extend past sunset. If there is any chance it does, fix the light first.

What Does the ACS Expect at Your Checkride?

The Airman Certification Standards (ACS) require you to demonstrate the ability to determine aircraft airworthiness, which includes working through an inoperative equipment decision from an actual maintenance log. Your designated pilot examiner (DPE) is looking for three things:

1. That you can apply the process, not just recite it
2. That you know your required equipment lists well enough to look at a squawk and immediately know which list to check
3. That you understand the hazard question is a real pilot-in-command decision, not a checkbox you rush through to get airborne

Reviewing the maintenance logbook and any existing squawks is part of your preflight - not an optional part. If there are open write-ups in the aircraft records that you have not read and evaluated, you have not completed your airworthiness check.

Key Takeaways

• FAR 91.213 is a four-step process: MEL check → required equipment check → hazard assessment → deactivate and placard. Answer yes to any step and the aircraft stays grounded.
• Most Part 91 general aviation aircraft do not have an approved MEL, so most pilots will start at Step 2.
• Required equipment lists - TOMATO FLAMES (VFR day), TOMATO FLAMES + FLAPS (VFR night), and GRABCARD (IFR) - must be memorized and understood, not just recited.
• Always check airworthiness directives and the POH in addition to the regulation lists - either source can make an item mandatory.
• The placard requirement exists to protect future pilots. Skipping it is not a minor administrative shortcut - it is a safety failure.