FAR Ninety-One Point Two Thirteen, the Inoperative Equipment Question Every Pilot Faces Eventually, and the Four-Step Decision That Keeps You Legal

FAR 91.213 exists to give pilots a structured decision process when something stops working. Work through four questions in order - the moment you answer yes to any one of them, you have your answer. Clear all four, and you likely have a path to fly.

This regulation is one of the most practically useful in Part 91. Understanding it turns what feels like a stressful judgment call into a checklist.

What Is FAR 91.213 and Why Does It Matter?

FAR 91.213 is the inoperative equipment regulation. It provides a framework for determining whether a malfunctioning item makes your aircraft unairworthy, or whether you can legally deactivate it, placard it, and fly.

Without this framework, pilots tend toward one of two failure modes: canceling flights unnecessarily because they’re unsure of the rule, or convincing themselves it’s probably fine and flying anyway. Both happen constantly. Both are avoidable.

The Four-Step Decision Framework

Work through these questions in order. Stop at the first yes.

Step 1: Is there an Airworthiness Directive (AD) that requires this item to be operative?

An Airworthiness Directive is a mandatory federal order issued by the FAA when an unsafe condition exists in an aircraft product. ADs can require inspections, modifications, replacements - and they can mandate that specific systems be functional before flight.

If an AD covers the broken item and requires it to be operative, there is no workaround. No placard. No “close enough.” The aircraft is grounded until the item is repaired. Your maintenance logs should reflect compliance with every applicable AD. If you’re uncertain what ADs apply to your aircraft, that’s a conversation for your next annual inspection.

Step 2: Is this equipment required by the FARs for the specific kind of flight you are conducting?

The key word is specific. Not whether the equipment is generally useful - whether it is legally required for day VFR, night VFR, or instrument flight.

FAR 91.205 lists required equipment for each category of flight.

For day VFR, the required items are:

• Airspeed indicator
• Tachometer for each engine
• Oil pressure gauge for each engine using a pressure system
• Manifold pressure gauge for altitude engines
• Altimeter
• Temperature gauge appropriate for engine type
• Fuel gauge showing usable fuel quantity in each tank
• Landing gear position indicator (retractable gear aircraft)
• Approved anti-collision light system (aircraft certificated after March 1996)
• Magnetic direction indicator (compass)
• Emergency Locator Transmitter (ELT)
• Safety belts for each occupant

Every item on that list is a no-fly item if it’s broken and you’re conducting day VFR. Know it cold - your checkride examiner will ask.

For night VFR, add to the day VFR list:

• Position lights (red on the left, green on the right, white showing aft)
• Approved anti-collision light (if not already required for your aircraft)
• Landing light (if operating for hire)
• Adequate source of electrical energy for all installed equipment
• Spare fuses in an accessible location, if the aircraft uses fuses

For instrument flight, add:

• Gyroscopic rate-of-turn indicator (turn coordinator)
• Slip-skid indicator (the ball in the inclinometer)
• Sensitive altimeter adjustable for barometric pressure
• Clock with a sweep seconds hand or digital display
• Adequate generator or alternator of sufficient capacity
• Gyroscopic pitch and bank indicator (attitude indicator)
• Gyroscopic direction indicator (heading indicator)
• Communication and navigation equipment appropriate for the route and clearance

Step 3: Is the item required by the aircraft’s Pilot’s Operating Handbook, its Equipment List, or by an approved Minimum Equipment List?

This step surprises many student pilots. The POH and aircraft equipment documentation carry regulatory weight - they are not just reference material. Some aircraft have sections in their POH, or in a separate Equipment List, that specify what must be operative for flight. If the documentation lists an item as required, it is required, even if it’s not on the 91.205 day VFR list.

This varies by aircraft make, model, and year of manufacture. You have to check your specific airplane’s documentation. It is not optional.

A note on Minimum Equipment Lists: an approved MEL is a formal, FAA-authorized document - aircraft-specific, requiring FAA approval and authorization from a Flight Standards District Office - that exhaustively lists every piece of equipment and spells out exactly what happens when each item fails. Airlines and some corporate operators use approved MELs. Most training aircraft and personally owned general aviation airplanes operating under Part 91 do not have one.

Step 4: If the answers to all three prior questions are no, what can you do?

FAR 91.213 opens a legal path forward. The inoperative item may be:

• Removed from the aircraft, with the cockpit control placarded and the removal recorded in the maintenance logbook, or
• Deactivated and placarded “INOPERATIVE” near the instrument or switch

If deactivating the item requires a maintenance action, that work must be performed and signed off by an appropriately certificated mechanic. After that, you as pilot in command must determine that the inoperative item does not constitute a hazard to the aircraft.

Why the Placard Is Not Optional

The placard is a legal requirement, not a courtesy. It is what transforms the situation from an overlooked discrepancy into a deliberate, documented decision. It informs the next pilot. It tells maintenance what needs attention. It is the proof that the inoperative item was identified and evaluated - not ignored.

No placard, no legal flight. That is the standard.

How to Apply This to Real Scenarios

Left nav light - day VFR, home before noon: Nav lights (position lights) are on the night VFR required list, not the day VFR list. If no applicable AD exists and the POH doesn’t list it as required for VFR operations, the answer to all four questions is no. Placard it inoperative, make a maintenance logbook entry, and fly. Call your mechanic from the ramp.

Attitude indicator not reading correctly - day VFR: The attitude indicator is on the instrument flight required list, not the day VFR list. It is not in the 91.205 day VFR column. Check your POH for aircraft-specific requirements. If you clear all four questions, it can legally be placarded for day VFR flight.

The safety determination, however, is real. A student pilot with 30 hours flying without an attitude indicator on a hazy afternoon is a different risk profile than a 500-hour pilot on a severe clear day. The regulation establishes a floor. Your judgment determines whether you should be above it.

Magnetic compass unreadable: The magnetic direction indicator is on the day VFR required list. The answer to question two is yes. The aircraft is grounded until the compass is functional. This is not a placard situation.

Pitot heat inoperative - clear summer morning, no visible moisture: Pitot heat is not on the day VFR required list. Check your POH. If you clear all four questions, you can placard and fly for a day VFR flight where icing is not a factor. But pitot icing can form at temperatures warmer than most pilots expect when humidity is high. If there is any possibility of encountering those conditions, that safety determination needs to be honest.

ELT battery expired: This has its own regulation - FAR 91.207 - separate from the inoperative equipment rule. ELTs have specific maintenance and inspection requirements governing when the battery must be replaced. Know them separately from 91.213.

What Your Examiner Is Looking For

The Private Pilot Airman Certification Standards specifically require knowledge of required equipment for day and night VFR and the ability to determine whether a discrepancy makes an aircraft unairworthy. FAR 91.213 is exactly what that standard is testing.

When a scenario comes up during your oral - something stopped working during preflight, what do you do - walk through the four questions out loud. AD? Required for this specific flight? POH requirement? Can it be placarded? Make the call and explain your reasoning. The examiner is not looking for a guess. They’re looking for the systematic thinking that framework produces.

A Note on Airworthiness

An aircraft is considered airworthy when it meets two conditions simultaneously: it conforms to its type design (matches the FAA-approved design) and it is in condition for safe operation. A broken item that passes the four-step analysis might still leave open the question of whether the aircraft is safe to fly. That determination rests with the pilot in command. The regulations establish the minimum. Judgment closes the gap.

When you determine an item is inoperative and fly with it placarded, make an entry in the aircraft maintenance records - not your personal pilot logbook. If the deactivation involved a maintenance action, it must be signed off by a certificated mechanic under FAR Part 43.

The placard is a temporary solution, not a plan. Get the item repaired on a reasonable timeline.

Key Takeaways

• FAR 91.213 provides a four-question framework for inoperative equipment: AD? Required for this flight? POH requirement? If all three are no, placard and document.
• The required equipment list in FAR 91.205 differs for day VFR, night VFR, and IFR - the analysis is always specific to the flight being conducted.
• The placard is legally required, not optional - it’s the documented proof that the discrepancy was evaluated, not ignored.
• Passing the legal analysis does not end the analysis. The pilot in command’s safety determination is a separate, mandatory step.
• Inoperative items must be documented in the aircraft maintenance records. Any deactivation requiring maintenance must be signed off by a certificated mechanic.