Minimum Equipment List Template

Redundancy in design generally means that failure or malfunction of one component doesn’t mean instant failure of the entire system. In various design applications, redundancy is accounted for using backup components. One example of this might be a backup generator that kicks in when power is lost to a machine. In aviation, one example of redundancy involves equipment, instruments, or onboard systems that can be inoperative for a specific aircraft for a specific flight. This is what is known as an aircraft minimum equipment list.

Airworthiness quantifies a plane or other aircraft’s suitability for completing a flight safely. Items on a minimum equipment list are those that are inoperative without compromising the aircraft’s airworthiness. Equipment and parts that aren’t on the MEL must be fully functional for flight. Even if a plane that is scheduled to fly has nonfunctional equipment, the flight can proceed if the equipment is listed on the FAA minimum equipment list.

The MEL should not be confused with a list of aircraft required equipment, which might include components that don’t affect airworthiness, such as passenger comfort items. It is also distinct from an aircraft safety equipment list, which includes personal flotation devices and emergency equipment unrelated to airworthiness. MEL aviation isn’t about cutting corners to complete a flight, but it does allow an operator to postpone or defer maintenance of equipment, avoiding loss of revenue or passenger discomfort.

When discussing minimum equipment lists, there are generally two types:

• Master Minimum Equipment List: This is a list of parts that may be inoperative for a flight, according to the manufacturer of the aircraft.
• Minimum Equipment List: This is a list of parts that an operator defers for future maintenance for a particular flight.

The MMEL is generally less restrictive and serves as a basis for the MEL. An operator may have additional criteria or stipulations that make the aircraft minimum equipment list more limited.  In order to use an MEL, aircraft manufacturers and operators must be authorized by the Federal Aviation Administration in the United States or similar agencies in other countries, such as the European Aviation Safety Agency.

When it comes to the MEL, one of the most important pieces of information is the deferment or the time period that a part needs to be brought back into service, usually quantified in days. This is the repair interval and it’s categorized according to length:

• Repair Interval A: Unspecified repair period, or listed on the specific MEL page for a part
• Repair Interval B: Part to be repaired within 3 consecutive days
• Repair Interval C: Part to be repaired within 10 consecutive days
• Repair Interval D: Part to be repaired within 120 consecutive days

The MEL should also indicate which equipment needs maintenance actions and which equipment needs operational actions. They are marked with an (m) and (o) respectively. Some equipment may require both types of actions and should be marked with both “(m)(o).”

A sample MEL will also indicate the particular part and an alphanumeric ID of some sort. For each component on the MEL, a basic MEL will include:

• Repair interval
• The number of total parts installed on the aircraft
• The number of total parts required (which should be less than the total parts installed, establishing redundancy)
• Placard status indicating whether the part has been labeled or tagged inoperative
• Type of action needed to bring the part back into use (maintenance, operational, or both)
• List of conditions to be met for the part to be inoperative during flight

Paper files can be subject to loss or destruction. A digital version of this list can be generated quickly and consistently and routed to all necessary parties instantly using the internet. Digital forms can be checked against an MMEL or other regulatory codes for compliance and other errors. Any processes or workflows involving MEL document control and management can also be automated with the right platform.

Fluix is your flight operations management solution for the digital management of an aircraft minimum equipment list. It is a powerful yet lightweight platform that can help you improve your processes related to MELs. This cloud-based platform works on mobile devices, making it ideal for airside and landside operations at airports and hangars. With powerful features such as electronic signing, form creation, and automation, your MEL processes can truly take flight.