Inoperable instruments and equipment

In plain English

You may fly with inoperative instruments or equipment only under an approved Minimum Equipment List (MEL) issued for that operator and aircraft. The item must be deactivated/placarded and the conditions of the MEL met. There is no informal "deferral" like the Part 91 process.

Key points

• An approved MEL is required to operate with inop equipment.
• Follow the MEL’s procedures and time limits exactly.
• Placard and record the inoperative item.

Common pitfalls

• Using the Part 91 inop-equipment process (91.213(d)) for a 135 flight.

*This is a plain-English summary for study only. The official 14 CFR text on this page is controlling — always read the current regulation and your operator’s ops specs.*