MEL, MMEL, NEF: What Are You Required to Have? [+ Free MEL Guide]

Are you required to have an MEL? Could your aircraft be grounded if you don’t have an NEF Program? MMELs, MELs, and NEFs (nonessential equipment and furnishing lists) allow you to operate even if some aircraft equipment and furnishings are inoperative.  Knowing which you need though can be confusing.

Did you know that the use of an MMEL as an MEL requires more than simply having the MMEL? Find out what other documents you need to have on board the aircraft. Download our free MEL guide for clear guidance on what you need, how to use it, and how to maintain it.


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MMEL Explained

Master Minimum Equipment List (MMEL): A master list of items on an aircraft that are allowed to be inoperative under specific conditions without impacting the safety of flight.

The MMEL is established by the aircraft manufacturer and approved by the national aviation authority. The goal of the document is to detail what equipment and furnishings can be inoperative without compromising safe operations. When developing the MMEL a number of factors are taken into consideration including:

  • Engineering and flight testing of failures
  • Effects of inoperative items on flight safety and the crew
  • Impact of multiple failures

MEL Explained

Minimum Equipment List (MEL): Based on the MMEL, it is an adapted list of items specific to a given aircraft/fleet aircraft that may be inoperative taking into consideration specific regulatory and operations limitations unique to each operator.

With an MEL, the operator can far more easily determine the conditions under which an aircraft can operate even with inoperative equipment, since it is more concise and customized to the aircraft/fleet and operator.

An MEL must also be approved by the aviation authority, but unlike an MMEL, which is designed to cover an entire aircraft series/models’ potential configurations, spanning years or even decades, an MEL can be fully customized to remove non-applicable items as well as add procedures. 

MEL customization is based on:

  • Aircraft type, variant, and serial number
  • Applicable regulations related to the type of operation, aircraft size and capacity, airworthiness directives, MMEL supplements, STCs, etc.; and special approvals granted to the operator (CAT II, PBN, RVSM, ETOPS…).

It is important to ensure that when customizing an MEL, it is never less restrictive than the MMEL.

What about nonessential equipment that cater to passenger convenience and entertainment? These are part of an Operator’s NEF Program instead.

NEF Explained

Nonessential Equipment and Furnishings Program (NEF): It is part of the MEL, but may be kept as a separate document. It outlines the steps operators may use to determine if a damaged, inoperative or missing item can be deemed as nonessential and therefore deferred.

If you have the LOA that allows you to use your MEL, or MMEL as an MEL for U.S. Part 91 operators, you may use an NEF Program to defer items deemed nonessential.

However, if you don’t have an NEF program, all inoperative, nonessential items need to be fixed before takeoff.

U.S. registered aircraft operating under Part 91 can obtain authorization to use the MMEL as an MEL, although it’s highly suggested that operators use this for domestic operations only.

MMEL as MEL (U.S. Registered, Part 91 Only)

If you want to use an MMEL as an MEL, there are however other documents you must have onboard in addition to the MMEL – refer to the MEL Guide for more information.

When using an MMEL as an MEL crews only have generic information available to them. Not all items included in the MMEL will be applicable to their specific aircraft or type of operation. It is important that crews be able to determine which deferrals are applicable to them.

  • A number of items in the MMEL will not indicate a specific number installed or number required. Crews will need to know which equipment is installed, how many units are installed, and the minimum number required based on applicable regulations and operational limitations.
  • The MMEL and M&O procedures will contain generic procedure statements. Crews will need separate guidance on where specific procedures can be found.
  • The MMEL will contain generic regulatory statements. Crews will need to know which regulations apply to each item and have copies of those regulations available to them in the aircraft.

Due to the generic nature of the MMEL, crews must be careful when selecting the appropriate deferral item. Some of the things they will want to consider are:

  • Modifications, Service Bulletins, STCs, etc.
  • Part numbers
  • Serial number ranges
  • Variant restrictions
  • Operating types
  • Installations of other equipment
  • Quantity of equipment installed

Creating an MEL that meets regulations and then keeping it up to date is very time consuming. Contact our team for advice and support. And don’t forget to download your complimentary MEL Guide:

Get Your Free MEL Guide

The Most Common Risks Operators Face Day to Day

Quick, accurate risk identification is essential for a successful operation. While some risks may be specific to a location, flight path, or aircraft, there are many that occur regularly and can be planned for ahead of time.

Through ARCrisk, ARC’s digital Risk Assessment Tool, flight departments log thousands of risk assessments every year. We’ve taken a look at the top 10 selected risk factors flight departments are facing and how to mitigate them. How do these compare to your top 10 factors and subsequent mitigations?

Read the full article and download the guide on ARC.

Flight Planning Codes Demystified [+ Free Guide]

A flight plan is a critical part of a flight and it is essential to ensure that it’s properly prepared. Unfortunately,mistakes are often made when completing them, due to lack of knowledge or confusion about regulations. It’s important to ensure your flight plans are going to ATC with the right codes to help you avoid clearance changes and delays. Errors on sample flight plans are also a frequent reason why Letters of Authorization are either delayed or not approved.

Our experts have compiled a free Flight Planning Guide with equipment checklists for operators and their planning providers to make sure their flight plan meets ATC’s and the FAA’s expectations.


Download Your Free Guide with Checklists


Flight planning codes for LOA approval

When applying for a Letter of Authorization (LOA), there is a lot of paperwork to prepare and the FAA wants to make sure everything is in order. For applications for LOAs A056, Data Link Communications (CPDLC/ADS-C), and B036, Oceanic and Remote Operations (RNP-10/RNP-4/RNP-2), a sample flight plan is required.

Since you’re requesting Data Link and PBN authorization for the aircraft, the FAA will specifically be checking whether the flight planning codes listed in ICAO Items 10 and 18 are correct for the aircraft capabilities. 

Unfortunately, there are often errors in this section, which end up causing delays in the approval of LOAs. While flight planning codes may seem like just a bunch of letters and numbers on paper, errors can have real consequences when received by ATC, such as inadvertent flight penalties or the inability to receive an in-flight clearance. Operators and planning providers must share the responsibility in correctly filing flight planning codes. 

Your flight planning code checklist

We’ve put together a list of important form items operators can run through to check the most common Flight Plan Form errors.

For the full list of codes you need to consider, download the Flight Planning Guide

Item 10

List the navigation and communication equipment and capabilities of your aircraft.

Item 10a

  • Review your data link codes (J codes).
    These codes will include “J1” through “J7”
    Most DLC-capable aircraft are capable of VDL M2. If your aircraft is VDL M2 capable then you need to have the “J4” code listed.
    There has been some confusion regarding this code and TSO C-160/160a compliance. TSO compliance relates to determining domestic enroute capability which affects Item 18, but does not affect this item.
  • Determine if you should include the “P2” code.
    If the aircraft is PBCS capable, “P2” should be included. If the aircraft is not PBCS capable, do not include this code. (Note that if your aircraft has Honeywell FMSs that have not yet been updated with a proper latency timer fix, then you should NOT include “P2.”)
  • Check if you will list a COM/, NAV/, or DAT/ entry in item 18.
    If you will be listing an entry in item 18, then add a “Z” code here.
    You will always list an entry in item 18 and need a “Z” code if your aircraft is data link capable.

Item 10b

  • Ensure the transponder code is correct.
    For example, if the aircraft has 1090 MHz ADS-B installed, which is very common, one of the “extended squitter” codes should be used. The most common code is L, but your aircraft may differ.

Item 18

List additional technical equipment codes to clearly communicate your aircraft capabilities. There are a lot of codes and a specific order, so errors in this section are frequent. Depending on your flight planning provider and their system, you may only have to do this once, when you set up your aircraft profile.

  • Check the code sequence.
    Keep the codes in the preferred sequence as indicated in the FAA’s flight planning brochure to prevent truncation of your flight plan resulting in an incomplete flight plan.
  • Ensure applicable RNP-4 codes are listed.
    If the aircraft is RNP-4 capable, the PBN/ entry must include L1, in addition to “A1” for RNP-10.
  • All data link equipped aircraft must include a DAT/ entry.
    Aircraft capable of US domestic en route CPDLC, without any known “push-to-load” message errors, will typically use the code DAT/1FANSE2PDC.
    Aircraft capable of US domestic en route CPDLC, with known “push-to-load” message errors, will typically use the code DAT/1FANSER2PDC.
    Aircraft not capable of US domestic en route CPDLC, but FANS equipped, will typically use DAT/1FANS2PDC.
  • Make sure the SUR/ entry is correct.
    If ADS-B is installed, it should be SUR/260A or SUR/260B, depending on the equipment.
    If the aircraft is PBCS capable/authorized, make sure to add “RSP180” to this entry.
    If the aircraft is not PBCS capable/authorized, do not enter an RSP code.
  • Make sure there are REG/, SEL/, CODE/, and OPR/ entries.
    These are all operator/aircraft specific and reflect the aircraft registration, aircraft SELCAL code, aircraft hexadecimal Mode S code, and the operator’s name, respectively.

Item 19

Include items specific to survival equipment and information for search and rescue teams. This section of the form usually isn’t transmitted to air traffic control, but the FAA considers it mandatory for LOA approval.

Finally, although not related to flight planning codes, we have seen the FAA taking notice of the fuel information as well. Here are a few key items to check:


Equal Time Point (ETP)

  • Ensure these calculations are included in the flight plan
    The equal time point is a point along the route from which it takes the same amount of time to return to the departure point as it would to continue to the destination.

Fuel Block: This is a detailed breakdown of fuel usage.

  • Ensure fuel listed meets requirements.
    ICAO specifies seven different fuel blocks that are to be present on the flight plan.
  • Check that your naming conventions are correct.
    Keep in mind that there are different naming conventions. For best results, it is recommended that you keep your fuel block as closely matched to ICAO’s terminology as possible.
    If you name your reserve fuel “reserve” or “RESV”, rename it to “contingency”, or “CONT”.
  • Check your back up fuel.
    Authorities want to see how you plan on using your fuel and if there is enough fuel planned in the event you would need to fly to an alternate airport.
    • Be sure to add 30 minutes of holding/final reserve fuel.
    • Be sure to add 5% contingency fuel (5% of the trip fuel).

Don’t forget to download our free Flight Planning Guide

Looking for more detail on each of these items? Our International Operations and Procedures Manual has expanded information with charts explaining each code in the appendices.

Contact us for any LOA support, and check out our free LOA Guide for more information.  

AviationManuals updates international operations service to conform with new flight planning codes

At AviationManuals a primary element of our services is ensuring our clients have the most up-to-date information about regulations, compliance, and requirements.

This month we’re announcing updates we made to our international operations procedures service in response to the new planning code requirements that were released by the Federal Aviation Administration (FAA) in November 2022.

The FAA had identified potential gaps in the codes currently available in the international flight plan format that can result in ambiguity on specific advanced navigation capabilities. To improve understanding between operators and ATS, the FAA has introduced new codes for any aircraft that intends to use these capabilities.

For example, the new codes allow operators to indicate if an aircraft is fitted with advanced RNP and related capabilities such as Radius to Fix (RF) or Time of Arrival Control (TOAC), as well as RNP-2 in either continental or oceanic airspace.

These new codes will be required for any aircraft that intends to use these capabilities within FAA- controlled airspace and are effective immediately.

In response, we have updated our international operation procedures (IOP) services to reflect the new requirements and codes. Subscribed operators have received a Sky Brief update about the change and will see the new procedures updated in their manuals at their next annual revision. This is just one of the hundreds of requirements we monitor and review across multiple regulatory environments to ensure our clients always have the most relevant and timely information at their fingertips.

For those wanting more information, we have subscription services for international operators that keep your team up to date.

AviationManuals Receives MEL Preamble Pre-Approval from Isle of Man: What it means for you

You probably think our business is safety.

And it is. But we are also so much more than that.

We spend much of our time working with agencies, partners, and industry leaders to provide the best possible outcomes for operators, particularly when navigating complex compliance and safety landscapes.

We recently announced that the Isle of Man granted “pre-approval of our Minimum Equipment List preamble,” and you can read about it here:

We are proud of the Isle of Man announcement since it reflects the high standards the entire team at AviationManuals always strives for. We want to continue to be the trusted partner that helps make running an operation easier for our clients.

Developing strong relationships and partnerships with regulators worldwide as well as strategic associations in business aviation, has been instrumental in helping to streamline approvals and applications.

So, even if your aircraft is not registered with the Isle of Man, this achievement demonstrates how we continually strive to make all our services more accessible and valuable to our customers.

While we continue to talk to companies across the industry about integrations, you can always stay up to date on our latest partnerships and integrations here. Alternatively, feel free always to reach out and tell us directly what partnerships or integrations you might like to see us pursue.

One partner, association, authority, and application at a time, we’re building the future of safety and compliance support.

Did you miss BACE? Here is what we found interesting

During NBAA-BACE last month, the AviationManuals team had the opportunity to meet clients and industry colleagues, attend educational sessions, and present to attendees with the FAA and Honeywell. Here are some takeaways from the event that our team thought was important. 

LOA Streamline Process  

There was a lot of interest at the event about the new FAA LOA Streamline Process that launched earlier this year. The simplified application process for Part 91 operators with new aircraft uses FAA-issued statements of compliance (SOC), which indicate the FAA has previously reviewed and approved the applicable documentation from the holding vendor. As a result, inspectors can approve LOA applications without a full review of all documentation, thereby shortening approval time from months to weeks.  

Workforce Challenges 

Workforce challenges were another main discussion point during BACE this year. From ground personnel to pilots, the whole industry is facing a shortage and is trying to navigate the best way to recover. As flight departments experience personnel changes, utilizing procedures manuals to ensure smooth transitions and SMS to monitor risks associated with change is more important than ever. 

Our CEO, Mark Baier, talked about the subject with Fast Company in the summer. Learn more here: Why is there an airline pilot shortage?

In addition, mental health was a newer topic that we were glad to see being discussed. We hope that sessions covering mental health and strategies to support employees’ overall wellness continue.  

SMS Challenges  

A subject in the show’s past editions, the SMS challenge continued to be a hot topic this year. With the expectation that the FAA will soon make it mandatory for Part 135 and SMS being on the NTSB’s Most Wanted List, operators had many questions about it. After working with hundreds of operators, we’ve created a practical SMS Guide to help you implement or improve SMS within your own department.


Another relevant talking point was sustainability. During the Newsmakers breakfast, Boeing Chief Strategy Officer Marc Allen answered questions about how to move forward in a more sustainable way and discussed the idea of “zero-impact over zero-emissions.” There were also sessions about Sustainable Aviation Fuel (SAF), climate risk, and the importance of environmental sustainability for the business aviation industry 

What we were up to 

Our team had packed schedules for the event showing the industry the upcoming features and integrations for ARCrisk and working with the FAA and Honeywell to speak about the latest updates operators need to know for international travel and how to navigate ramp inspections. 

Did we miss you at the show? We would love to meet, answer any questions you have, and understand how we can assist you further.  

Telephone: +1 (240) 546-4030

Partnerships and Integrations Bring Improved Safety and Compliance Services

AviationManuals has partnered with industry leaders and aviation authorities to streamline your safety and compliance experience with access to additional services, features, and reduced processing times for approvals.

As part of our mission to provide operators with the only integrated approach for SMS, compliance, and procedures all in one platform we have developed strong working relationships, partnerships, and integrations with numerous support service vendors including flight planning services, avionics manufacturers, and maintenance facilities. All of these will allow us to better serve clients by offering reduced operator workload, easier reviews, and minimal aircraft downtime.

Partnerships and Integrations include:

  • Bermuda Civil Aviation Authority (BCAA)
  • ARINCDirect / Collins Aerospace
  • Universal UVGo
  • Scott IPC
  • Starr Insurance Companies
  • Isle of Man Aircraft Registry (IOMAR)

Check out our Partnerships and Integrations page for a full list of details.

These established partnerships are just one more way we extend industry knowledge and convenience to our customers. Our team is continuing to work on the development of key partnerships and integrations so that we can introduce even more improvements to work flows and special services and events.

Join the VIP of Safety

If you are a business aviation flight department, FBO, or commercial drone operation that needs a better way to do business, let’s talk!

Contact us

AviationManuals Earns IS-BAH PSA Recognition

AviationManuals broadens its long-standing relationship with IBAC by expanding support for FBOs seeking IS-BAH certification.  

ROCKVILLE, MD, August 23, 2022 – AviationManuals, the leading provider of procedure development services and Safety Management System (SMS) software, has received IS-BAH (International Standard for Business Aircraft Handling) PSA (Programme Support Affiliate) recognition. By becoming a PSA, AviationManuals has expanded its support solutions for FBOs to include those who wish to meet the IS-BAH standard or seek IS-BAH certification.

“FBOs are busy managing their own businesses and may have limited resources for figuring out SMS on their own,” said Mark Baier, CEO of AviationManuals. “ Many operators can benefit from our assistance to get them prepared for IS-BAH certification,” Baier said.

“While we have always helped FBOs with compliance and safety, we can now also support operators as a recognized PSA with IBAC,” said Kevin Honan, Senior Operations Advisor at AviationManuals. “We can assist FBOs in understanding, complying with, and maintaining the standards of the IS-BAH Program.”

Developed by the International Business Aviation Council (IBAC) in 2014, the IS-BAH standard uses SMS to help FBOs manage workplace safety and prevent aircraft handling incidents and workplace injuries.

“IS-BAH certification is quickly becoming a popular way for FBOs to demonstrate their quality and professionalism,” continued Baier. “We want to support our clients looking to achieve this endorsement by providing them with our years of extensive operational support and SMS experience.”

About AviationManuals: Founded in 1996 AviationManuals’ philosophy is to make operations manuals and Safety Management Systems (SMS) accessible to every business aviation flight department, FBO and commercial drone operation. Headquartered in the Washington DC metro area, they support over 4,500 operators worldwide and are the leading provider of manual development services and Safety Management System (SMS) software for business aviation flight departments, aircraft management companies, and independent owner / operators around the globe. For more information visit 

Updated EU Ramp Inspection Program (SAFA) Service Offerings

Our popular SAFA Inspection Manual Service has been updated to conform with the latest guidance released by the European Union Aviation Safety Agency (EASA). As the Ramp Inspection Program expands, more operators are concerned about being prepared for an inspection, leading to an increase in customers getting SAFA Inspection Manuals. In the first half of 2022 we prepared almost the same number of SAFA Inspection Manuals as we did in all of 2021.


The updated Ramp Inspection Manual (RIM) Issue 3.0 from EASA does not require you to make changes to your flight department operations. Rather, it expands the guidance for inspectors performing checks clarifying differences for general aviation operators vs commercial. Additionally, the revisions give more information about items to be reviewed and pre-described findings.

Staying up to date is a vital part of safety. We have incorporated these changes, which in this case, will benefit both operators and inspectors in ensuring ramp checks continue to go smoothly.

EU Ramp Inspection Program

The program is utilized inside and outside of the EU and regulates the SAFA and SACA Inspections performed on aircraft to help facilitate safety and compliance. This includes checks on items such as pilot licenses, procedures, safety equipment, and aircraft condition.

These inspections may be performed in any EU Member State. They may also be initiated in non-EU Member States that are participating in the program, including Canada, Singapore, and most recently Brazil.

Ramp inspectors may check a list of over 50 items. Having an easy-to-navigate digital “binder” that address each item with evidence makes it quick to identify and locate compliance items. Additionally, it can help you to identify any areas of non-compliance prior to traveling to a participating State.

Interested in our SAFA Inspection Manual service? Request a quote.