Inoperative Equipment

Part 91.213 describes how to deal with inoperative equipment in aircraft used in Part 91 operations.

Generally, if a piece of inoperative equipment is found before a flight your options are:

• Cancel the flight
• Perform maintenance before the flight
• Defer maintenance of the item

Some instruments and equipment must be repaired before flight, including:

• Those required for airworthiness of the aircraft
• Those required by an AD to be operative
• Those required for specific operations by Part 91, including:
  • Day VFR equipment 91.205(b)
  • Night VFR equipment 91.205(c)
  • IFR equipment 91.205(d)

Aircraft with a Minimum Equipment List

Some aircraft (usually large or complex aircraft) will be certified with a Minimum Equipment List (MEL). An MEL will specify which equipment can be inoperable, and how it should be handled.

An MEL is issued to an aircraft's operator via a letter of authorization for a specific type and registration number. It then becomes mandatory for that aircraft. With an MEL, equipment cannot be deferred via

91.213(d).

If a piece of inoperative is found, it should be noted in the aircraft maintenance records, or a record specific to this purpose.

91.213(a)

Aircraft without a Minimum Equipment List

In an airplane without an MEL, maintenance of an inoperative item can be deferred as long as the equipment is not required per:

• The aircraft's VFR-day type certification
• The aircraft's equipment list, or the Kind of Operations Equipment List (KOEL)
• An applicable AD
• 91.205 or any applicable section of Part 91 for the operation being conducted

In this case, the equipment shall either be:

• Removed from the cockpit, the cockpit control placarded, and a record made in the maintenance log
• Deactivate and placarded "Inoperative"
  • If the deactivation requires maintenance, it must be done by an authorized mechanic

91.213(d)