Can someone explain the use of an MEL?

jasc15

jasc15

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Joe
I've read about it in several places a number of times, had my instructor explain it, and it still doesn't make sense to me. It seems that its part of a decision process dealing with inoperative equipment.
First you would determine if the equipment is required for the type of flight (i.e., VFR day). If not, then you see if it is part of an AD. If still no, then this is where I am confused. How does an MEL com into play, and is it the same as a maintenance deferral? Could someone explain in step-by-step plain English?
 
jasc15 said:
I've read about it in several places a number of times, had my instructor explain it, and it still doesn't make sense to me. It seems that its part of a decision process dealing with inoperative equipment.
First you would determine if the equipment is required for the type of flight (i.e., VFR day). If not, then you see if it is part of an AD. If still no, then this is where I am confused. How does an MEL com into play, and is it the same as a maintenance deferral? Could someone explain in step-by-step plain English?
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Start by using this document:

http://fsims.faa.gov/PICDetail.aspx?docId=5C4470D5145F35828525734F00766624

Also AC 91-67 http://rgl.faa.gov/Regulatory_and_G...4a06437c5fa862569d900744d86/$FILE/Chap1-2.pdf
 
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jasc15 said:
I've read about it in several places a number of times, had my instructor explain it, and it still doesn't make sense to me. It seems that its part of a decision process dealing with inoperative equipment.
First you would determine if the equipment is required for the type of flight (i.e., VFR day). If not, then you see if it is part of an AD. If still no, then this is where I am confused. How does an MEL com into play, and is it the same as a maintenance deferral? Could someone explain in step-by-step plain English?
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Actually, it's more of an "either/or" thing...you EITHER use 91.213(d), which allows you to defer certain inoperative equipment when you DON'T have an MEL; or you use the MEL, which is authorized by the other sections of 91.213.

Following the links R&W posted, you'll see discussion of the MMEL, which is the "Master" Minimum Equipment List for a particular type. If you're a part 91 operator, you'd basically get a Letter of Authorization from the FAA to use the MMEL as your MEL, which still requires a little judgement. A good example is some of the 4-bladed propeller mods for King Airs...the MMEL allows deferral of an inoperative autofeather system on a King Air. Some of the prop mods, however, predicate Vmc on the failed engine having a feathered propeller rather than a windmilling propeller, and the AFM supplement states that the autofeather system has to be operative. Therefore you can't defer it, even though you're authorized to use the MMEL, and the MMEL says you CAN defer it.

For 121 or 135 operations, on the other hand, the operator selects the applicable items from the generic MMEL to create an MEL specific to the serial number aircraft, the FAA approves it, and you can then use the MEL as your sole source of information for equipment deferral. In the King Air example above, the operator simply wouldn't copy the autofeather section from the MMEL to the airplane's MEL, and the pilot wouldn't have the contradicting information.

If you want to look at a specific MMEL, here's a link to the Baron MMEL: http://fsims.faa.gov/wdocs/mmel/be-55%2058%2095%20r6.pdf

David
 
For the average light plane owner/pilot, 91.213(d) is generally a much easier way to go rather than the MEL process. While you are required to know the MEL system for the Commercial and even Private practical tests, for the average Private Pilot not planning on flying big iron or for a living, it's something best memorized for the test and then forgotten, but 91.213(d) should be learned well and put to use.
 
Ron Levy said:
For the average light plane owner/pilot, 91.213(d) is generally a much easier way to go rather than the MEL process. While you are required to know the MEL system for the Commercial and even Private practical tests, for the average Private Pilot not planning on flying big iron or for a living, it's something best memorized for the test and then forgotten, but 91.213(d) should be learned well and put to use.
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For the aircraft owner obtaining an MEL is not a difficult task and will open up more usefulness of your aircraft.
 
Rotor&Wing said:
For the aircraft owner obtaining an MEL is not a difficult task and will open up more usefulness of your aircraft.
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Depends what you own, and for the planes most folks here are flying (light singles without MMEL's), it isn't all that simple a thing to do, and it's unlikely to add usefulness to such a plane. In those cases, 91.213(d) is easier and simpler, and carries no operational penalties of which I am aware compared to getting an MEL.
 
Ron Levy said:
Depends what you own, and for the planes most folks here are flying (light singles without MMEL's), it isn't all that simple a thing to do, and it's unlikely to add usefulness to such a plane. In those cases, 91.213(d) is easier and simpler, and carries no operational penalties of which I am aware compared to getting an MEL.
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And what "operational penalties" are you referring to?

So when was the last time you obtained a MEL for an airplane?
 
What is the use of an MEL? Well, if you rented the airplane and something quit, you don't have to worry about getting the airplane back to the owner or explaining why you will not be bringing it back.
 
So, how would having an MEL increase the usefulness of an aircraft vs. just labeling something inop and flying home? Peggy, why wouldn't you just label whatever item inop and fly home?
 
Ted DuPuis said:
So, how would having an MEL increase the usefulness of an aircraft vs. just labeling something inop and flying home? Peggy, why wouldn't you just label whatever item inop and fly home?
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Remember that labelling something "inop" doesn't solve the problem. If the equipment is required, you can throw "inop" labels all over the place and you still couldn't legally fly it home. And if it's not required, but maintenance is required for removal or deactivation (and it's not a "preventive maintenace" item), you'd need a mechanic to take care of it and return the aircraft to service before you could fly it home.

Kind of tough for a commercial operator in the middle of the night on a cargo run.
 
midlifeflyer said:
Kind of tough for a commercial operator in the middle of the night on a cargo run.
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The fact that one has an MEL doesn't necessarily mean one can just fly with malfunctioning equipment. There are things which must be done equivalent to the 91.213(d) procedures before you launch. The big difference is that you have preapproved rules to go by regarding what you can fly without rather than having to work it out yourself when it happens. Since the planes most of us here have are pretty simple, so are the issues, and having an MEL doesn't make much difference if you know what you're doing. When you get into more complicated planes (multiengine, multisystem, pressurized, multicrew, etc), MEL's make a lot of sense.
 
Ted DuPuis said:
So, how would having an MEL increase the usefulness of an aircraft vs. just labeling something inop and flying home? Peggy, why wouldn't you just label whatever item inop and fly home?
Click to expand...

Ted,

Whether or not one wants or needs an MEL is a matter of personal preference. I would suggest someone look at the MMEL for their aircraft and determine if it would benefit them. Remember that for a pilot to inop a piece of equipment (legally) it requires several steps and also a signoff by a A&P before the aircraft departs. On some items on the MEL (remember it varies depending upon aircraft) the pilot can simply label the item inop, make a writeup in the MEL log and proceed.

Here is the FAA's guidance on MEL's for Part 91 Operators: http://fsims.faa.gov/PICDetail.aspx?docId=5C4470D5145F35828525734F00766624

There is a good flowchart at 4-42 and 4-43 that may answer some questions.
 
Ron is correct in that it doesn't make sense to have a MMEL on a light single. How can you defer a inop alternator when you only have one in the first place. A light aircraft just doesn't have enough redundant equipment to justify using a MMEL

It does make sense though on more complex aircraft. We often use the MMEL to defer items on the jets. It just allows us relief to keep the airplane moving until we can meet up with parts and maintenance. On anything you defer under the MEL there may be (M) Maintenance, (O) Operations or both that must be complied with to be able to continue operations.
 
LearDriver said:
Ron is correct in that it doesn't make sense to have a MMEL on a light single. How can you defer a inop alternator when you only have one in the first place. A light aircraft just doesn't have enough redundant equipment to justify using a MMEL
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Like most people you don't really understand MEL's, which is understandable. MEL's doesn't necessarily involve only items that are redundant.

Take the example of a fuel gauge. If a pilot is preflighting their small airplane and discover the left fuel gauge inop they cannot "inop" it via 91.213 and fly. However under a MEL it may state "Gauge may be inop provided there is a reliable means of determining fuel quantity". The procedure could further state that means as a calibrated dip stick or simply topping the tank off with a know quantity.
 
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Well, MEL in MY airplane is altimeter/oil pressure/whiskey compass/speedo...
Everything else is optional depending upon the flight conditions...
Says who?
Me, the PIC... The same guy who puts his certificate on the line every time he fires up and takes off...
Besides, who is running off and calling the FSDO to ask if they made a boo boo by continuing the flight home after this or that failed in flight? Let's get real...

denny-o
 
There seems to be a problem with R&W's link to the FAA Order 8900.1 section. For whatever reason, it's only showing the first few lines of that section. You may have to go into FSIMS from the top (http://fsims.faa.gov/PICResults.aspx?mode=EBookContents) and open the section from there. You're looking for Volume 4, Chapter 4, Section 2. As you'll see, there's a boatload of work involved, especially if there's no Master MEL already existing for your aircraft type. Further, the MEL for your plane will be quite specific to your plane -- any STC's, instrument/equipment changes from how it came from the factory, etc, must be accounted for.

If you want to know if there's a MMEL for your type (which saves a lot of work in developing a MEL for your plane), see http://fsims.faa.gov/PICResults.aspx?mode=Publication&doctype=MMEL. Note, for example, that there are no MMEL's for single-engine Cessnas below the C-208 Caravan or any single-engine Pipers below the Malibu.

All things considered, I don't think you'll find this process superior to 91.213(d) for a light single such as most of us here fly, but YMMV.
 
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I'm afraid this isn't much clearer to me after all this talk. Specifically where I am going with this is knowing how to answer the examiner on my checkride when he asks, "Your widget is not functioning. Can you still fly?". I can go through the list of required VFR day equipment , but as I understand, it doesn't end there. What is the complete and correct answer?
 
jasc15 said:
I'm afraid this isn't much clearer to me after all this talk. Specifically where I am going with this is knowing how to answer the examiner on my checkride when he asks, "Your widget is not functioning. Can you still fly?". I can go through the list of required VFR day equipment , but as I understand, it doesn't end there. What is the complete and correct answer?
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The process most of us would use is as described in 91.213(d), and your best bet in that situation is to pull out your FAR/AIM, open it to that page, and step through the process. Your instructor should go through this with you before the test. You'll also need the AFM/POH for your plane and its equipment list, but you should have those handy for the ground portion of the PTS anyway. Just work down the four steps of the 91.213(d) process one at a time, showing how each applies to your aircraft and its documentation, and describing what you'd do for that widget. Note that the "Kinds of Operations" list is normally in Section 2 (Limitations) of the AFM/POH if you have one.

You may also have need of a copy of the Type Certificate Data Sheet for aircraft that predate the AFM/POH requirement (or don't otherwise have one the way many pre-1977 Pipers do). You can find a copy of that for your plane on the FAA web site at http://www.airweb.faa.gov/Regulatory_and_Guidance_Library/rgMakeModel.nsf/MainFrame?OpenFrameSet. You'll also want a copy of any AD's applicable to your plane, or know where to find them, if they set additional requirements.

As for MEL's, unless the examiner provides one and asks you to answer questions about it (and that's not likely to happen on a Private ride), about all you need do say that if you have one, you'll check it and follow the steps in it to determine what to do. Of course, it would be nice if your instructor pulls one off the FAA MMEL web site mentioned above, and shows you this before the test just so you know what you'd be looking at, but not every instructor is that thorough unless prodded.
 
jasc15 said:
I'm afraid this isn't much clearer to me after all this talk. Specifically where I am going with this is knowing how to answer the examiner on my checkride when he asks, "Your widget is not functioning. Can you still fly?". I can go through the list of required VFR day equipment , but as I understand, it doesn't end there. What is the complete and correct answer?
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First question...Does your airplane have an FAA-authorized MEL? If so, there will be a Letter of Authorization in the front of the MEL specifically naming the operator and N-number of the aircraft.

I suspect that you DON'T have an MEL for your airplane, in which case you have to look at 91.213(d), which is the regulation authorizing flight with inoperative equipment. The rest of 91.213 is largely irrelevant if you don't have an authorized MEL.

(d) Except for operations conducted in accordance with paragraph (a) or (c) of this section, a person may takeoff an aircraft in operations conducted under this part with inoperative instruments and equipment without an approved Minimum Equipment List provided—
(1) The flight operation is conducted in a—
(i) Rotorcraft, non-turbine-powered airplane, glider, lighter-than-air aircraft, powered parachute, or weight-shift-control aircraft, for which a master minimum equipment list has not been developed; or
(ii) Small rotorcraft, nonturbine-powered small airplane, glider, or lighter-than-air aircraft for which a Master Minimum Equipment List has been developed; and
(2) The inoperative instruments and equipment are not—
(i) Part of the VFR-day type certification instruments and equipment prescribed in the applicable airworthiness regulations under which the aircraft was type certificated;This is generally Part 23 or CAR 3 for light airplanes. It MAY go back to Aeronautical Bulletin 7A if your airplane is old enough.

(ii) Indicated as required on the aircraft's equipment list This document is generally in your AFM/POH, and lists components that are required for flight...for example, on my Maule, it says the generator is required, or on the Kinds of Operations Equipment List for the kind of flight operation being conducted The KOEL is another list that MAY be included in the AFM/POH...not all airplanes have it. This one generally has columns for Day, Night, VFR, and IFR next to each item that will be checked if the item is required for that particular type of operation;
(iii) Required by §91.205 or any other rule of this part for the specific kind of flight operation being conducted 91.205 is the "basic instruments and equipment" regulation...other regulations in Part 91 require certain pieces of equipment...landing lights if the flight is "for hire", anticollision lights, ELT, oxygen, etc. Technically, this is probably where you'd also determine whether your flight manual supplements require specific equipment; or
(iv) Required to be operational by an airworthiness directive This can be a toughie...you have to know what ADs apply to your airplane.; and
(3) The inoperative instruments and equipment are—
(i) Removed from the aircraft, the cockpit control placarded, and the maintenance recorded in accordance with §43.9 of this chapter; or a lot of people miss this "or".

(ii) Deactivated and placarded “Inoperative.” If deactivation of the inoperative instrument or equipment involves maintenance, it must be accomplished and recorded in accordance with part 43 of this chapter; and
(4) A determination is made by a pilot, who is certificated and appropriately rated under part 61 of this chapter, or by a person, who is certificated and appropriately rated to perform maintenance on the aircraft, that the inoperative instrument or equipment does not constitute a hazard to the aircraft. This is a "catchall"...kind of like the "careless or reckless" reg.

An aircraft with inoperative instruments or equipment as provided in paragraph (d) of this section is considered to be in a properly altered condition acceptable to the Administrator.
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Clear as mud? Might be best to pick some specific examples to go through with your instructor (or with the committee here ;))

David
 
OK, a little clearer, I guess.

Let's say its the position lights, and VFR-day.

1) Not needed for VFR-day flight

2) Not part of an AD (maybe it is, maybe it isn't. I'd have to find out)

3) See if it's on an MEL?

4) ...?
 
jasc15 said:
OK, a little clearer, I guess.

Let's say its the position lights, and VFR-day.

1) Not needed for VFR-day flight

2) Not part of an AD (maybe it is, maybe it isn't. I'd have to find out)

3) See if it's on an MEL?

4) ...?
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First off, you'll want to cite the specific references that say it's not needed for VFR-day flight. As Ron and I suggested, your best option is to go through 91.213(d) step by step.

Second, you seem to have an incorrect notion in your head of what an MEL is. An MEL is a document that the operator requests and receives specific authorization from the FAA to use. An MEL is not part of the aircraft's equipment list, a Kinds of Operations Equipment List, or anything else that would apply to 91.213(d). If you're using 91.213(d), an MEL doesn't factor into the equation at all.
 
One problem here is that the aircraft documents which must be referenced vary with aircraft make, model, and year. It sure would be a lot easier if I were sitting down and going through the steps and documents with you, and that's what your instructor should be doing. It really would make much more sense that way rather than trying to blindly talk you through documents I can't see.
 
I'll sit down with my instructor this weekend and go over this in more detail. Thanks for all the help; now I know better which questions to ask.
 
Dr. O said:
Well, MEL in MY airplane is altimeter/oil pressure/whiskey compass/speedo...
Everything else is optional depending upon the flight conditions...
Says who?
Me, the PIC... The same guy who puts his certificate on the line every time he fires up and takes off...
Besides, who is running off and calling the FSDO to ask if they made a boo boo by continuing the flight home after this or that failed in flight? Let's get real...

denny-o
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You're right of course. Any of us has the choice whether to intentionally violate the rules and to accept the consequences if caught. But this thread is about understanding the rules, not about the risk of getting caught.

After all, since ignorance is not a defense anyway (even though it may be bliss), it usually makes sense to understand the rule before deciding that it's okay to violate it.
 
Dr. O said:
Well, MEL in MY airplane is altimeter/oil pressure/whiskey compass/speedo...
Everything else is optional depending upon the flight conditions...
Says who?
Me, the PIC... The same guy who puts his certificate on the line every time he fires up and takes off...
Besides, who is running off and calling the FSDO to ask if they made a boo boo by continuing the flight home after this or that failed in flight? Let's get real...

denny-o
Click to expand...

midlifeflyer said:
You're right of course. Any of us has the choice whether to intentionally violate the rules and to accept the consequences if caught. But this thread is about understanding the rules, not about the risk of getting caught.

After all, since ignorance is not a defense anyway (even though it may be bliss), it usually makes sense to understand the rule before deciding that it's okay to violate it.
Click to expand...

Also note that there's a difference between "continuing the flight" and "take[ing] off an aircraft with inoperative instruments or equipment", as specified in 91.213.
 
jasc15 said:
OK, a little clearer, I guess.

Let's say its the position lights, and VFR-day.

1) Not needed for VFR-day flight

2) Not part of an AD (maybe it is, maybe it isn't. I'd have to find out)

3) See if it's on an MEL?

4) ...?
Click to expand...

Joe, pull out 91.213 and read it. One of the problems in training in this area is that so many CFIs start with 91.205 and compound the problem by elevating its importance with silly mnemonics.

The real starting point is 91.213. If you read it, you'll see that the part about the MEL is separate from 91.213(d) which goes into how to determine equipment airworthiness without a MEL.

In your flow, the first question is whether your airplane has MEL. That's =not= the equipment list in the POH (I know a lot of people think it is). It's a separate document, especially approved by the FAA for your specific airplane. Unless your airplane has one (probably doesn't – I have heard of training airplanes that do, but it's very rare), the only thing you need to know about MELs is to understand what they are.

For those position lights in your question, if your airplane doesn't have a MEL, you go to 91.213(d); it tells you where to look and what to do, although, as Ron points out, exactly what you look at in certain parts of the flow, depends on your airplane and its age.
 
I have read 91.213 many times, but i seem to have a mental block with it.

Let's see if i have this right:

91.213(a) Is there an MEL for the plane that includes the inop equipment along with a LOA?

91.213(b) describes the conditions under which an MEL can be obtained/issued

91.213(c) sounds like the department of redundancy department

91.213(d) In the absence of an MEL:
1 The plane must be a non-turbine aircraft, etc. or have a Master MEL
2 Inop equip is not part of VFR-day (as applicable), not part of 91.205, not part of an AD
3 Inop equip must be removed or placarded
 
Close... ;)

91.213(c) says that if a commercial operator has an MEL & LOA, they can't use 91.213(d). IIRC, somewhere in 135 (and probably the other referenced sections), it says you can't use 91.213(d), but I'm too lazy to look it up for sure.

There's a LOT of legalese in that reg...and the scope of what you need to look at is a lot broader than it first appears.
 
Rotor&Wing said:
Like most people you don't really understand MEL's, which is understandable. MEL's doesn't necessarily involve only items that are redundant.

Take the example of a fuel gauge. If a pilot is preflighting their small airplane and discover the left fuel gauge inop they cannot "inop" it via 91.213 and fly. However under a MEL it may state "Gauge may be inop provided there is a reliable means of determining fuel quantity". The procedure could further state that means as a calibrated dip stick or simply topping the tank off with a know quantity.
Click to expand...

I guess after 20 years of using them, I must have been using them wrong the entire time. Thanks for educating me.
 
There was this flight school (no longer in business) that used a complex aircraft for commercial training with fuel gauges marked INOP. It was okay because the MEL allowed it so long as the fuel was filled-up to the tabs prior to each flight.
 
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