Required maintenance (FAR interpretation)

[RotaryWingBob]

My understanding is that anything listed in the limitations section of an aircraft maintenance manual is mandatory. The question is whether an inspection procedure listed elsewhere in the manual is also mandatory. A&P,IA "A" says yes, A&P,IA "B" says no.

In this case, the procedure is a 100 hour inspection (having nothing whatever to do with part 135 or rentals). If an abbreviated inspection is conducted (ie. one which does not include all of the items listed in the maintenance manual), is the aircraft airworthy from a legal standpoint?

I'm not asking whether this is necessary smart (I know the answer to that, I think ), simply whether it is legal.

 

[TMetzinger]

I think that if the 100 hour inspection were required, then all the items on it are required.

If there's no requirement for a 100 hour inspection, then the work done could just be written up and the airplane returned to service. I don't think you can count it as a 100 hour inspection though.

Of course, if a 100 hour inspection isn't required by regs, why would you do one?

Disclaimer - this answer is based on logic, not on a careful read of the regs and any published interpretations on them. Therefore it is worth exactly diddly+squat.

 

[flyingcheesehead]

If there's no requirement for a 100 hour inspection, then the work done could just be written up and the airplane returned to service.

Uhhh, Tim, you might want to change that to "aircraft." Look who you're replying to.

 

[RotaryWingBob]

I think that if the 100 hour inspection were required, then all the items on it are required.

Yeah, but. If it's not in the limitations section, and is therefore not signed off by the FAA, is it required to be legally airworthy?

 

[TMetzinger]

OK, you're asking if the inspection procedure laid out in the manual that isn't part of the limitations section is mandatory?

Is there a service manual for the aircraft? If you have a procedure laid out for the 100 hour inspection laid out in the service manual, my opinion is that it is mandatory, as you would note that you completed a 100 hour inspection in accordance with FAR XXX and service manual section YYYY.

I'm pretty sure that mechanics MUST do the service in accordance with the service manual, so any procedures for the inspections laid out in the service manual would be mandatory.

 

[Tim]

sigh.... what kind of Plane make, model, and S/N? What year? Is it used for hire? What color is it?

 

[RotaryWingBob]

OK, you're asking if the inspection procedure laid out in the manual that isn't part of the limitations section is mandatory?

Is there a service manual for the aircraft?

Please read my original post.

 

[RotaryWingBob]

sigh.... what kind of Plane make, model, and S/N? What year? Is it used for hire? What color is it?

Your point is? I already said that it's not part 135, not rental. Oh yeah. It's not a plane either.

 

[Tim]

Then no its not.

 

[gismo]

I know that Beech has a many page inspection form for Bonanzas and Barons and that a copy is in the service manual, but many shops use their own annual inspection form with a different set of items to check. I believe that outside the limitations section of a service manual, nothing is mandatory. Otherwise manufacturers could force operators to comply with anything they felt like without the FAAs blessing. For instance Lycoming could put a "requirement" that all engine overhauls must be done at the factory.

 

[Stache]

To answer your question correctly I will have to assume you are conducting a 100-hour inspection on your aircraft and its being operated as a Part 91 aircraft.

Sorry but I have to quote several FAR rules to answer your question so bare with me.

The FAR 43 rules require a mechanic in accordance with FAR 43.15 “Each person performing an annual or 100-hour inspection shall use a checklist while performing the inspection. The checklist may be of the person's own design, one provided by the manufacturer of the equipment being inspected or one obtained from another source. This checklist must include the scope and detail of the items contained in appendix D to this part and paragraph (b) of this section.”

The key here is 43.15(c)(1) is the mechanic going to use their own checklist in accordance with 43 Appendix D or the manufactures recommended checklist in the manual?

If the mechanic uses the manufactures checklist now they are required in accordance with FAR 43.13 that states: § 43.13 Performance rules (general).
(a) Each person performing maintenance, alteration, or preventive maintenance on an aircraft, engine, propeller, or appliance shall use the methods, techniques, and practices prescribed in the current manufacturer's maintenance manual or Instructions for Continued Airworthiness prepared by its manufacturer, or other methods, techniques, and practices acceptable to the Administrator, except as noted in §43.16. He shall use the tools, equipment, and test apparatus necessary to assure completion of the work in accordance with accepted industry practices. If special equipment or test apparatus is recommended by the manufacturer involved, he must use that equipment or apparatus or its equivalent acceptable to the Administrator.

Using the manufacture checklist will require your mechanic to follow all the limitations in the maintenance manual if the checklist calls them out. This is a hard rule.

However if the A&P mechanic uses Part 43 Appendix D (abbreviated inspection) they have to follow: FAR 43.15 Additional performance rules for inspections.
This checklist must include the scope and detail of the items contained in appendix D to this part and paragraph (b) of this section.
(2) Each person approving a reciprocating-engine-powered aircraft for return to service after an annual or 100-hour inspection shall, before that approval, run the aircraft engine or engines to determine satisfactory performance in accordance with the manufacturer's recommendations of—
(i) Power output (static and idle r.p.m.);
(ii) Magnetos;
(iii) Fuel and oil pressure; and
(iv) Cylinder and oil temperature.

We have to keep in mind the FAA does NOT approve maintenance manuals they only accept them. Many maintenance manuals say “FAA Approved”, but its wrong. Having said that if the mechanic is following his 100-hour checklist and finds an item where would they go to find the limitations for the part? The rule is FAR 43.16

FAR 43.16 Airworthiness limitations.
Each person performing an inspection or other maintenance specified in an Airworthiness Limitations section of a manufacturer's maintenance manual or Instructions for Continued Airworthiness shall perform the inspection or other maintenance in accordance with that section, or in accordance with operations specifications approved by the Administrator under part 121 or 135, or an inspection program approved under §91.409(e).

The mechanic has to follow the maintenance manual limitations it the law under Title 49 U.S. Code. This is where FAR 43.13 Performance rules (general) come in ans states SHALL.

Stache
A&P/IA

 

[RotaryWingBob]

Thanks, Stache, and your assumptions about part 91 are correct.

The subject came up in the context of maintenance on Robinson helicopters. A local factory-trained A&P/IA has proposed that instead of doing the 100 hours inspection as specified in both the R22 and R44 maintenance manuals, to do a more limited inspection every 50 hours (this is what he does on his own R22, which he teaches in).

Now I'm good with doing an inspection every 50 hours -- it might turn up a problem before it got more serious. My question was that if we also substitute that limited inspection for the 100 hour, would we be legal? And I think you answered that.

Now, putting legality aside for a minute, we have to decide from a safety perspective if we want the full 100 hour (which is essentially the same as an annual), or the more limited inspection.

Thanks for your help on the legal side!

 

[cwyckham]

Now, putting legality aside for a minute, we have to decide from a safety perspective if we want the full 100 hour (which is essentially the same as an annual), or the more limited inspection.

I write Instructions for Continued Airworthiness for various modifications, and sometimes there's really good reasons for those inspection intervals (and sometimes I make them up out of thin air to cover my a**). Since you don't know which is which, I'd suggest that your reduced 50 hour inspection should be designed so that every 100 hour item gets done at least once every second inspection.

Chris

 

[RotaryWingBob]

I write Instructions for Continued Airworthiness for various modifications, and sometimes there's really good reasons for those inspection intervals (and sometimes I make them up out of thin air to cover my a**). Since you don't know which is which, I'd suggest that your reduced 50 hour inspection should be designed so that every 100 hour item gets done at least once every second inspection.

Chris

That's pretty much the conclusion I've reached. I'm a chicken, I guess, but I intend to stay a live chicken

I think we'll do the non-required 50 hr plus the 100 hr described in the Robinson maintence manual.

 

[Tim]

To answer your question correctly I will have to assume you are conducting a 100-hour inspection on your aircraft and its being operated as a Part 91 aircraft.

Sorry but I have to quote several FAR rules to answer your question so bare with me.

The FAR 43 rules require a mechanic in accordance with FAR 43.15 “Each person performing an annual or 100-hour inspection shall use a checklist while performing the inspection. The checklist may be of the person's own design, one provided by the manufacturer of the equipment being inspected or one obtained from another source. This checklist must include the scope and detail of the items contained in appendix D to this part and paragraph (b) of this section.”

The key here is 43.15(c)(1) is the mechanic going to use their own checklist in accordance with 43 Appendix D or the manufactures recommended checklist in the manual?

If the mechanic uses the manufactures checklist now they are required in accordance with FAR 43.13 that states: § 43.13 Performance rules (general).
(a) Each person performing maintenance, alteration, or preventive maintenance on an aircraft, engine, propeller, or appliance shall use the methods, techniques, and practices prescribed in the current manufacturer's maintenance manual or Instructions for Continued Airworthiness prepared by its manufacturer, or other methods, techniques, and practices acceptable to the Administrator, except as noted in §43.16. He shall use the tools, equipment, and test apparatus necessary to assure completion of the work in accordance with accepted industry practices. If special equipment or test apparatus is recommended by the manufacturer involved, he must use that equipment or apparatus or its equivalent acceptable to the Administrator.

Using the manufacture checklist will require your mechanic to follow all the limitations in the maintenance manual if the checklist calls them out. This is a hard rule.

However if the A&P mechanic uses Part 43 Appendix D (abbreviated inspection) they have to follow: FAR 43.15 Additional performance rules for inspections.
This checklist must include the scope and detail of the items contained in appendix D to this part and paragraph (b) of this section.
(2) Each person approving a reciprocating-engine-powered aircraft for return to service after an annual or 100-hour inspection shall, before that approval, run the aircraft engine or engines to determine satisfactory performance in accordance with the manufacturer's recommendations of—
(i) Power output (static and idle r.p.m.);
(ii) Magnetos;
(iii) Fuel and oil pressure; and
(iv) Cylinder and oil temperature.

We have to keep in mind the FAA does NOT approve maintenance manuals they only accept them. Many maintenance manuals say “FAA Approved”, but its wrong. Having said that if the mechanic is following his 100-hour checklist and finds an item where would they go to find the limitations for the part? The rule is FAR 43.16

FAR 43.16 Airworthiness limitations.
Each person performing an inspection or other maintenance specified in an Airworthiness Limitations section of a manufacturer's maintenance manual or Instructions for Continued Airworthiness shall perform the inspection or other maintenance in accordance with that section, or in accordance with operations specifications approved by the Administrator under part 121 or 135, or an inspection program approved under §91.409(e).

The mechanic has to follow the maintenance manual limitations it the law under Title 49 U.S. Code. This is where FAR 43.13 Performance rules (general) come in ans states SHALL.

Stache
A&P/IA

And the answer is............

 

[Stache]

The short answer is; You have to follow the limitations in the current manufacturer maintenance manual to be legal reference FAR 43.13(a).

A owner is responsible for the airworthiness of the aircraft FAR 91.7 and the mechanic is required by law Title 49 U.S. Code to follow the limitations in the manual. And FAR 91 Subpart E requires owner or operate to make sure the mechanic follows FAR 43.13(a).

Stache

 

[John Reed]

The short answer is; You have to follow the limitations in the current manufacturer maintenance manual to be legal reference FAR 43.13(a).

A owner is responsible for the airworthiness of the aircraft FAR 91.7 and the mechanic is required by law Title 49 U.S. Code to follow the limitations in the manual. And FAR 91 Subpart E requires owner or operate to make sure the mechanic follows FAR 43.13(a).

Stache

Stache,

Could you explain what you mean when you are talking about the limitations in the maintenance manual? When I look at the C172 R/S manual I don't see much. I see the life limited components section. When you refer to limitations; do you also mean the limits set by the manufacturer as to what is a hazard to flight. For example; a fuel seep, or leak is not considered a hazard to flight (if it's not in an enclosed area) but a running leak is.

To quote from another source:
"The manufacturer sets the service limits. If the manufacturer says the leak is within service limits, it is, and you may return the aircraft to service with this notation, “The leak is within the manufacturer’s service limits.” However, at the next scheduled servicing, fix the leak."


Thanks.

 

[Stache]

This is a little long, but bare with me again.

When I refer to “limitations” I should explain it more in detail. There are several types of limitations placed on aircraft by the manufacture type certificate (T/C), flight manual, and maintenance manual. The limitation sections of these document is spelled out on Title 49 Part 21, which covers certification of all aircraft. Part 21 calls out how and when limitations are required in several sections; FAR 21.5, 21.15, 21.31, 21.41, 21.50, 21.93, 21.253, 21.275, 21.463 and FAR 43.16 maintenance.

FAR 43 is a maintenance rule, which states when mechanics or pilots perform maintenance and inspection we have to follow the limitations set by the manufacturer's maintenance manuals. Sorry for quoting the rule but I don’t want t make a mistake.

§ 43.16 Airworthiness limitations.
Each person performing an inspection or other maintenance specified in an Airworthiness Limitations section of a manufacturer's maintenance manual or Instructions for Continued Airworthiness shall perform the inspection or other maintenance in accordance with that section, or in accordance with operations specifications approved by the Administrator under part 121 or 135, or an inspection program approved under §91.409(e).
[71 FR 44188, Aug. 4, 2006]

The manufacturer's does set limitations, but remember alterations such as field approvals and STC’s also have limitations that may change the or add to the aircraft or rotorcraft operating manuals and are required by reference.

If you look at your airworthiness certificate it states for your aircraft to be airworthy it has to 1) meet the type design (T/C) and 2) be in a condition for safe operation (limits). The limits can be life limited components listed on the T/C, which are hard times, limitations by airworthiness directives (ADs) required by part 39 mandatory, and limitations in the maintenance manuals such as fuel leaks. If it says you can leak a 6-inch stain in 24-hour and you lead a 3-inch stain the aircraft is within the limitations and considered airworthy. As long as it stays within the limitation it does not have to be repair or replaced it meets the limitation. This is not to say you shouldn’t fix a fuel leak I would just common sense, but it is still within the limitation. Same goes for INOP instrument they don’t have to be fixed if properly deferred in accordance with part 91.213. They can go in for an annual inspection and be signed off for return to service in accordance with FAR 91.213 and the aircraft still be airworthy.

The flight manual limitations are approved in most cases. You will have to check your flight manual and see if it says (FAA APPROVED) in the limitation sections most are some are not. However if you check the T/C you will notice many of the limitations are on the T/C and are required such as airspeed limitations, powerplant instrument marking, powerplant limitations, maneuver limits and so on. They are approved because they are on the T/C, field approval or STC.

To throw a wrench into this discussion I have read and seen many engine manuals reference Service Letter and Service Bulletins in their maintenance manuals and say they are mandatory.

[“There exists a difference of opinion among field inspectors concerning the manner in which manufacturer maintenance manual material, including service letters and service bulletins, could be enforced by the FAA. FAR 43.13 requires all persons to use methods, techniques, and practices acceptable to the Administrator while performing aircraft maintenance. The manufacturer's maintenance manuals, service bulletins, and service letters have always been regarded as a source of acceptable data for complying with FAR 43.13(a) and (b); however, such acceptability does not, in itself, impose an enforcement or mandatory compliance requirement.

The office of the Chief Counsel has advised that the provisions of the manufacturer's manuals, letters, and bulletins, with relation to specific inspection procedures, may be enforceable by means of an airworthiness directive (AD) or other specific rule. In addition, manufacturer data contained in a type certificate data sheet or specification may be enforceable under FAR 43.13. Reference FAA Order 8620.2 (dated 11/02/1078)”]

FAR 43.13 requires for maintenance to follow the current maintenance manual.

I hope this shed some light on the subject.

Stache

 

[John Reed]

It sure has shed some light on the subject. Thanks for responding in such detail.