R22 Airworthiness past 2200 hrs

[Rich1]

Looking for the collective wisdom and advice...  I have a 2004 R22 Beta II which is meticulously maintained but will reach 2200 hrs TT within the next year.  Engine was topped at 1700 hrs and compressions are very strong...all 78s.  Blackstone oil analysis every 50 hrs says motor is pristine. Main Rotors also replaced at 1700 hrs...they had 500 hrs at time of install so will have only a 1000 hrs remaining when we hit the 2200 HR mark.

 

Couple of questions for the veteran owners...1)  can the ship be flown (part 91) private use past the 2200 HR mark? I'm guessing this strong engine would go to 2700 or 3000 hrs which would time out the MR blades 2)  would it make more sense to sell the hull at 2200 hrs as well as part out the blades w 1000 hrs left.  3) or do a field overhaul keeping the current blades?

 

Looking at the logs closely, the only item I see critical is new spindles will be needed at 2200 as these are the originals...

 

Other questions/options I'm missing?

 

Hope some long time owners can share some seasoned thoughts or experiences?   Thanks in advance..

[superstallion6113]

I've never worked on anything but multi engine turbine powered military helicopters, but damn a Black Hawk is still under warranty at 2500 hrs. Surprised to see it's reaching the end of it's lifespan at 2200hrs.

[rick1128]

Rich,

 

According to Chapter 3 of the R22 maintenance manual, for your R22 to remain in a legal airworthy condition, you must overhaul the engine in accordance with the Lycoming recommendations and do a 12yr/2200 hour inspection/overhaul on the rest of your helicopter. I have heard some owner talk about changing the airworthiness over to experimental category. From what I can find out, this is not a legal option with the FAA. Also keep in mind that generally helicopter engines run at higher power settings and temperatures than the same engines in an airplane. So do you really want to run that engine that long?

[rotormatic1]

 

Couple of questions can the ship be flown past the 2200 HR mark?

 

As long as you replace the parts listed in the airworthiness limitations section of the maintenance manual, the ship is airworthy. See:

 

http://www.faa.gov/about/office_org/headquarters_offices/agc/pol_adjudication/agc200/interpretations/data/interps/2011/MacMillan.pdf

[Rich1]

Rich,

 

According to Chapter 3 of the R22 maintenance manual, for your R22 to remain in a legal airworthy condition, you must overhaul the engine in accordance with the Lycoming recommendations and do a 12yr/2200 hour inspection/overhaul on the rest of your helicopter. I have heard some owner talk about changing the airworthiness over to experimental category. From what I can find out, this is not a legal option with the FAA. Also keep in mind that generally helicopter engines run at higher power settings and temperatures than the same engines in an airplane. So do you really want to run that engine that long?

 

Hi Rick,

 

Appreciate the seasoned advice.... I'm just trying to explore options as the ship is not up against it's 12 year, and the ongoing oil analysis/monitoring seems to show little or no wear going on in the engine...guess it's going to come down to fatique, which is always a difficult variable indeed. It's also a conundrum as Frank Robinson de-rated the engine from 160 down to 120 for the very reason of reduced wear and fatigue as opposed to the 269s and others than run nearly 100% power almost all of the time...

 

 

Really appreciate the advice...

 

rich

[apiaguy]

I need a list of the FAA approved parts that are time limited on the r22 to give more info...but generally rotormatic is correct...you do not have to overhaul the engine. What does the actual section on the r22 say? I was under the impression the 12 year limit is also not required for part 91 in the. 22. Any body have access to the manual?

[Rich1]

I need a list of the FAA approved parts that are time limited on the r22 to give more info...but generally rotormatic is correct...you do not have to overhaul the engine. What does the actual section on the r22 say? I was under the impression the 12 year limit is also not required for part 91 in the. 22. Any body have access to the manual?

 

Thanks partner for the additional insights! I've accounted for all of the life limited parts in the engine and airframe logs. I think the fundamental question remaining is whether the engine must be overhauled at the 2200 HR mark as per Lycoming's recommended TBO and if not, does it deem the entire ship as unairworthy? Especially when it is operated Part 91.

 

The FAR is pretty clear that the PIC determines if the ship is airworthy under Part 91 but I'm not sure if the manufacturers recommendations override that?

[Rich1]

Sorry for the duplicate....

Edited October 18, 2011 by Rich1

[apiaguy]

Ok, to sum up what rotormatic's link said it is the interpretation by the FAA that says you don't have to do manufacturers service bulletins or service letters. Those are not required unless operating under part 135. (unless part of an airworthiness directive) So the answer is NO, you do not have to overhaul the engine. As long as compressions pass the mechanics comfort level and the engine is not making metal, you may operate it legally as LONG as you'd like. Many airplanes make 2500, 3000 +.

[Rich1]

Ok, to sum up what rotormatic's link said it is the interpretation by the FAA that says you don't have to do manufacturers service bulletins or service letters. Those are not required unless operating under part 135. (unless part of an airworthiness directive) So the answer is NO, you do not have to overhaul the engine. As long as compressions pass the mechanics comfort level and the engine is not making metal, you may operate it legally as LONG as you'd like. Many airplanes make 2500, 3000 +.

 

Greatly appreciated...thank you for the help and insights...fly safe...r

[rick1128]

Rich,

 

The way the Robinson maintenance manual is worded I don't believe that the engine overhaul is optional. The way insurance companies operate, they could use this against you if you have a claim. I have attached a copy of Page 3.3 from the R22 maintenance manual. While inspectors may say that engine overhauls are optional, if they look at the wording here, they may differ on that opinion.

Edited October 19, 2011 by rick1128

[rick1128]

For some reason I lost the attachment.

Robinson RH22 MM page 3.2.pdf

[apiaguy]

I completely understand where you are coming from Rick. An Insurance company may use any trick they like to not pay a claim but they would have to have it in writing that the aircraft must be maintained according to the maintenance manual which I'm sure Robinson's insurance company probabally does.

On the issue of airworthiness (which is only defined by the FAA, which is the only regulatory requirement to operate an aircraft) an aircraft needs only a few things to be considered "airworthy". (part 91 legal that is)

1. Registration

2. Airworthiness certificate

3. Current annual inspection

4. Operating handbook (poh)

5. Current weight and balance

 

So the airworthiness of the aircraft as pertaining to the operation in excess of 2200 hours or 12 years would fall under the "current annual inspection" description.

The portion of the R22 manual I was looking for was the one that was stamped or scripted as the FAA approved list of time limited components. The part you attached had no inscription or approval attached.

 

Overhaul of components such as transmissions and engines on helicopters are usually listed seperately from the list of time limited components and usually are not FAA approved times. That means you don't have to follow the Manufacturers recommendation on overhaul intervals to be legal unless 1)it's part of an airworthiness directive or 2) you operate for hire (part 135).

Now I am not a Robinson guy and have not read their manual so again I'd need more info, but as rotormatics atachment alluded to....the FAA does not allow manufacturers to dictate to aircraft owners every move as to what is required to maintain airworthiness as that would allow a company to control the market of its product unfairly. The FAA basically does allow this to happen if you operate as a commercial air carrier (part 135) as now you are exposing someone other than yourself and private individuals to risk.

Disagree if you like or think it is risky or stupid to operate any aircraft not in accordance with the maintenance manual... but illegal it is not.

 

Per the Type Certificate Data Sheet:

 

NOTE 3. Retirement time of critical components is contained in the FAA approved "AIRWORTHINESS

LIMITATIONS" section of the Robinson R22 Maintenance Manual. The values of retirement or service life

and inspection intervals cannot be changed without FAA Engineering approval.

 

So If someone with this section of the manual could please post it we could wrap it up.

Edited October 19, 2011 by apiaguy

[iChris]

Rich,

 

The way the Robinson maintenance manual is worded I don't believe that the engine overhaul is optional. The way insurance companies operate, they could use this against you if you have a claim. I have attached a copy of Page 3.3 from the R22 maintenance manual. While inspectors may say that engine overhauls are optional, if they look at the wording here, they may differ on that opinion.

 

 

For some reason I lost the attachment.

Robinson RH22 MM page 3.2.pdf

The Interpretation (rotormatic1 posted above) makes clear that unless the R22 maintenance information in the maintenance manual is in a separate airworthiness limitation section and is FAA approved, it is not mandatory. See interpretation page 2 paragraph 2, page 3 paragraph 3, and page 6 question #6

 

Such a section is even referenced in the R22 type certificate (H10WE) page 7, Note #3.

 

The attached page below is from the R22 maintenance manual and lists the mandatory requirements. The Administrator considers all other information in section 3 "acceptable" methods and practices. This all falls in line with FAR 43.13.

 

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.

 

Here's the deal stated on page 2 of the interpretation:

 

"The key here is that if other methods, techniques, and practices are used, they must be acceptable to the FAA. The maintenance provider is not free to ignore the manufacturer's manual and either do nothing or perform the maintenance in such a manner that would not be acceptable"

 

"If a maintenance provider performed maintenance on a product and deviated from the methods, techniques, and practices in the applicable maintenance manual, in order for the FAA to sustain a violation of 43.13a, the agency would have to show how the methods, techniques, and practices used was unacceptable."

 

Therefore, if you decide to deviate you just can't say the engine need not be overhauled because there's no mandatory interval. You need to develop an alternative interval that ensures the continued airworthiness of the engine and airframe. In other words you need some method in place. Whether it's acceptable to the administrator is now on you.

 

Given, if there's no accidents, incidents, or injuries the light of investigation may never reach you.

 

Edited October 21, 2011 by iChris

[rotormatic1]

Here is something about notes on type certificate data sheets addressing mfg's recommendations.....

 

http://fsims.faa.gov/wdocs/orders/8620_2a.pdf

Edited October 19, 2011 by rotormatic1

[apiaguy]

iChris said: "Therefore, if you decide to deviate you just can't say the engine need not be overhauled because there's no mandatory interval. You need to develop an alternative interval that ensures the continued airworthiness of the engine and airframe. In other words you need some method in place. Whether it's acceptable to the administrator is now on you. Given, if there's no accidents, incidents, or injuries the light of investigation may never reach you."

 

 

Industry standard for a piston engine is at each annual inspection or 100 hour inspection; to see that all AD's are up to date, the cylinder compressions are sufficient, there is no metal in the filter, engine operates properly and at normal temperatures and pressures.

 

oh.. and thanks for posting the airworthiness limitation section. Good discussion

Edited October 19, 2011 by apiaguy

[iChris]

iChris said: "Therefore, if you decide to deviate you just can't say the engine need not be overhauled because there's no mandatory interval. You need to develop an alternative interval that ensures the continued airworthiness of the engine and airframe. In other words you need some method in place. Whether it's acceptable to the administrator is now on you. Given, if there's no accidents, incidents, or injuries the light of investigation may never reach you."

 

 

Industry standard for a piston engine is at each annual inspection or 100 hour inspection; to see that all AD's are up to date, the cylinder compressions are sufficient, there is no metal in the filter, engine operates properly and at normal temperatures and pressures.

 

oh.. and thanks for posting the airworthiness limitation section. Good discussion

 

That's correct, since it's a documented practice in line with FAR 43.15c and Appendix D to Part 43. If the aircraft was not used for compensation or hire it could be operated part 91 under the annual inspection only requirements of 91.409a. In that case (with respect to the engine) there would be no required engine overhaul. You could continue on each year as long as the engine passes the annual inspection requirements in Appendix D to Part 43.

 

Appendix D to Part 43—Scope and Detail of Items (as Applicable to the Particular Aircraft) To Be Included in Annual and 100-Hour Inspections

 

(d) Each person performing an annual or 100-hour inspection shall inspect (where applicable) components of the engine and nacelle group as follows:

 

(1) Engine section—for visual evidence of excessive oil, fuel, or hydraulic leaks, and sources of such leaks.

 

(2) Studs and nuts—for improper torquing and obvious defects.

 

(3) Internal engine—for cylinder compression and for metal particles or foreign matter on screens and sump drain plugs. If there is weak cylinder compression, for improper internal condition and improper internal tolerances.

 

(4) Engine mount—for cracks, looseness of mounting, and looseness of engine to mount.

 

(5) Flexible vibration dampeners—for poor condition and deterioration.

 

(6) Engine controls—for defects, improper travel, and improper safetying.

 

(7) Lines, hoses, and clamps—for leaks, improper condition and looseness.

 

(8) Exhaust stacks—for cracks, defects, and improper attachment.

 

(9) Accessories—for apparent defects in security of mounting.

 

(10) All systems—for improper installation, poor general condition, defects, and insecure attachment.

 

(11) Cowling—for cracks, and defects.

Edited October 24, 2011 by iChris

[superstallion6113]

For some reason I lost the attachment.

 

Reading that it looks like it says the airframe, control system, drive system, and rotor systems must be overhauled at 2200hrs, but the engine overhaul requirements it says to refer to Lycoming Service Instruction 1009.

[rick1128]

Reading that it looks like it says the airframe, control system, drive system, and rotor systems must be overhauled at 2200hrs, but the engine overhaul requirements it says to refer to Lycoming Service Instruction 1009.

 

Where the problem comes in is that the Robinson Maintenance Manual states that 'the engine MUST be overhauled in accordance with Lycoming overhaul recommendations.' Unfortunately the word MUST does not give you a lot of wiggle room. Most other helicopter maintenance manuals will just refer you to the engine manufacturer's maintenance manual or service letter. Robinson does not. It has been my experience with the Feds that the word 'must' pretty much saids it all.

[iChris]

 

 

On 10/23/2011 at 1:08 PM, superstallion6113 said:

Reading that it looks like it says the airframe, control system, drive system, and rotor systems must be overhauled at 2200hrs, but the engine overhaul requirements it says to refer to Lycoming Service Instruction 1009.

It depends on who said “must”. Did Lycoming say you must? Did Robinson Helicopters say you must? Or did the FAA say you must. The FAA’s “Must” is the one that counts.

The R22 maintenance manual Airworthiness Limitations are in Section 3 on page 3.3 (not page 3.2). Page 3.3 is FAA approved and sets forth each mandatory (must do) replacement times, structural inspection intervals, and related structural inspections. An engine overhaul was not included in those airworthiness limitations.

As long as the owner complies with section 3 page 3.3 in the R22 maintenance manual, the aircraft and engine can be maintained under FAR 91.409a, 43.15c, and Appendix D to Part 43 in an airworthy condition. To fully understand you may need to reread the above posts and the supporting documentation.

“As a general proposition, manufacturer's maintenance manuals, service bulletins, and inspection programs (with limited exceptions not pertinent here) are not FAA-approved and are not mandatory; nor are subsequently issued changes to maintenance manuals or inspection programs. If they were, and compliance were required, this would be tantamount to private entities issuing "rules" of general applicability without meeting the notice and comment requirements of the APA,”

“As with the requirements for FAA-approved operating limitations in an AFM, Appendix G requires that the Airworthiness Limitations section be segregated and clearly distinguishable from the rest of the document. The section must set forth each mandatory replacement time, structural inspection interval, and related structural inspection procedure. It must contain a separate statement in a prominent location that reads: "The Airworthiness Limitation section is FAA approved and specifies.”

REF LINK:

https://www.faa.gov/sites/faa.gov/files/faa_migrate/interps/2011/MacMillan_2011_Legal_Interpretation.pdf

“Some OEM’s have placed mandatory language such as “shall,” “must,” and “will” on their TCDS that imply that compliance with TCDS notes is mandatory. However, in the absence of regulatory language, or an AD that makes such TCDS notes mandatory, compliance with such notes is not mandatory.”

REF LINK:https://www.faa.gov/documentLibrary/media/Order/Order_8620.2B.pdf

 

Edited June 9, 2023 by iChris
Update Links

[superstallion6113]

I agree that the FAA limitations for the aircraft would obviously trump what the Robinson MIMs say.

[r44guy]

Ichris, thanks for the very informative post. If makes things much easier to understand.

[roundwing]

IChris has it right.

 

The Dec 2011 edition of Sport Aviation Magazine has an article by Mike Busch on this very subject.

Good read, you may be able to see it on line at eaa.org.

 

The TBO recommended by the Engine Manufacturer is not required for Part 91 operations.

 

The Airworthiness Limitations section of the POH, the one listed by IChris for the R-22 is what you must follow.

 

Check each of the components listed to make sure they are not time out any you are good to go.

[avbug]

I think the fundamental question remaining is whether the engine must be overhauled at the 2200 HR mark as per Lycoming's recommended TBO and if not, does it deem the entire ship as unairworthy? Especially when it is operated Part 91.

 

TBO is a recommended interval, as other posters have noted, which doesn't become mandatory until incorporated in the maintenance requirements of other operating sections (eg, Part 121, Part 135, etc). Under Part 91, you may operate the engine "on condition."

 

Other posters are also correct that you may place yourself in legal jeopardy with respect to insurance and liability if you operate over TBO. Engines may be operated well beyond TBO safely, but if you do have a failure and damage the aircraft, or hurt yourself or passengers or persons or property on the ground, you're going to have to defend your decision to operate beyond TBO. When an opposing attorney or prosecutor holds you against the standard of a manufacturer overhaul recommendation and paints you as one who elected to operate beyond that threshold, you may find yourself in an unwinnable situation. You may find yourself held criminally negligent, civilly liable, and without insurance coverage. It's a very real concern.

 

In order to be airworthy, two standards must be met: the aircraft (and associated appliances and components) must be fully in compliance with the type certification (and any amendments thereto, such as AD's and STC's), and it must be in a safe condition for flight. Both standards are always required, and always parallel; unless are both fully satisfied, the aircraft, engine, or component isn't airworthy.

 

If you can show that the engine is within tolerances specified by the manufacturer, then you can show that it still meets it's certification criteria, and is safe for flight; you can also put yourself in jeopardy by operating beyond manufacturer recommended overhaul times because 14 CFR 91.13 always applies (careless and reckless operation) and is commonly used in enforcement action. Outside of administrative law (FAA), you are faced with other standards and duties; if a court holds against you because you are determined to have failed your duty to maintain the airplane safely (say, compressions were good but a rod developed a crack and caused an engine failure), you could become civilly liable, or even criminally liable. Imagine losing the engine while flying over a populated area and ending up killing someone during the subsequent autorotation. You can see where that might end up.

 

It sounds like the maintenance on the subject helicopter is being taken very seriously, with a close eye on components, limits, intervals, times, etc. That's excellent and proactive, and it's good that you're asking the questions now. You've received some good counsel on the subject.

 

The bottom line is that TBO is a recommendation, not a limit, outside of certificate operations (121, 135, etc). TBO is also a misunderstood concept, because it really applies in a very practical sense only to fully remanufactured engines, or to "first-run" engines that have never been overhauled. In a legal sense, it's an ongoing value which is subject to change; TBO can be increased by operators who show that their maintenance allows the engine to operate for longer periods, and it can be decreased as well when evidence is produced which shows it doesn't last as long as intended. I've worked in shops where the TBO of certain powerplants was increased by several hundred hours, in 50 hour increments. You don't have the benefit of such a program or such maintenance, however, over repetitive inspections, teardowns, and overhauls.

 

To be considered "overhauled," an engine must only meet minimum tolerances and specifications. An engine may actually be inspected and found to be in tolerance, and signed off as "overhauled." Many pilots and owners don't realize that an engine which has been "overhauled" may actually have many or most of the same components in the engine; components that are high time, which have been removed, inspected, found to be in tolerance, and put back in the engine. There is no standard of "overhaul" saying that X number of components must be replaced. It doesn't work that way. Some tend to think that once the engine has been signed off as "overhauled," it should go another 1800, 2000, or 2200 hours, whatever the applicable TBO for that powerplant may be. That's entirely untrue, however; because "overhauled" could mean almost anything was done or not done to the engine, at the time of "overhaul."

 

In your case, you appear to be describing an engine which is "first run," or which has never been overhauled. If this is the case, then you're working off the original date of manufacture, with what started life as a zero time engine from the time of measuring the current TBO interval. Bear in mind that TBO is a recommendation because it's very common for the engine to arrive at TBO in varying states of repair; an engine that's had several jugs replaced, for example, arrives at TBO as a different engine; some of it is new, some of it is old, and some of it is high time while some of it is not. Not all engines arrive at TBO the same way, either. Some are fried by the time TBO rolls around, while others can go much longer.

 

From a maintenance perspective, we always recommend that the dollar value to overhaul is set aside with every flight based on TBO as well as operating conditions; if you have a 2200 hour TBO, include in your hourly cost to operate the overhaul or replacement cost for that engine, based on TBO. If you're hard on your equipment or don't operate it frequently or operate it in a rough environment (sandy, for example, or freezing), you may be looking at overhaul or replacement sooner, meaning your hourly costs preparing for that time to come, will be higher.

 

Compression tests are good and sell aircraft, but mean very little. They're sort of the laymans way of making himself feel good about the engine. Compression tests tell you more about what needs attention than they do about the actual health of the engine; listening to air leaking through a case breather, or through the induction or exhaust tells you about servicing rings, or intake or exhaust valves or seats, but doesn't really tell you much about the engine itself. Owners and operators often look at the compression test as something like a blood pressure exam, like it means something, and it really doesn't. Don't be swayed by good compression values.

 

Compression values change significantly between a hot engine and a cold one, between test sets, and between different people doing the test, even if done in the same relative period of time. They can be artificially inflated during the test, or inadvertently lowered. It's not uncommon to find compressions higher at a 100 hour or annual inspection than they were the last time; compressions shouldn't go up, in theory, but the reality is that they vary with who is doing the test, the equipment, the engine temperature, recent operating practices, etc. Don't get too wrapped up in what the compression test tells you, because it usually isn't telling you as much as you think.

 

I mention this regarding compression tests because it's easy to get lead down the primrose path by thinking the engine is healthier than it is, based on compression tests. You indicated that you're doing regular spectrometric oil analysis, however, which is a much better view of the health trends of the engine. Taking various inspection aspects together, including oil analysis and compression, gives a more comprehensive picture of what's going on. You're clearly proactive by doing the oil analysis, and that should be an important tool in your assessment of how long you want to keep operating the engine, as should each aspect of the ongoing inspection process.

 

One thing you may want to consider, if you're going to continue operating beyond TBO, is decreasing maintenance intervals; if you were formerly inspecting every 50 hours, perhaps every 25 hours should be your new target. This shows increased vigilance, and attention, and may allow you to compensate for changes in trends sooner, as they happen. As the engine gets higher in time, trend changes may be expected to occur over shorter intervals; the wear may increase or you may see a sudden trend in oil consumption, compression change, elevated metals, etc. Decreasing inspection intervals is a very proactive way to more closely monitor what's going on with your equipment. It also increases costs substantially, so it's not a decision to be taken lightly, obviously.

 

Your base question here is whether you can legally operate beyond TBO and the answer is yes. You can. Manufacturers try to limit their liability by adding wording such as "must" and "mandatory," but this doesn't change the fact, and one manufacturer (eg, Robinson) can't set limitations for another manufacturer (eg, Lycoming). The question was raised regarding wording in the Type Certificate Data Sheet for the Robinson R22, regarding manufacturer recommendations being mandatory; Robinson doesn't have the authority to make them mandatory, nor to set policy for the engine manufacturer. The FAA doesn't have the authority to grand this authority to Robinson.

 

Manufacturers will try to tell you that a service bulletin, service letter, or other maintenance item is mandatory using language such as "must," but the manufacturer can't make it mandatory. If a service letter is introduced describing an inspection as mandatory, the owner doesn't need to comply unless it's specified in the limitations section of the approved maintenance publication in an FAA approved edition (original issuance, or mandated by airworthienss directive later). If the manufacturer wants it mandatory, the manufacturer needs to go through the rule making change process to get an AD issued.

 

 

The FAR is pretty clear that the PIC determines if the ship is airworthy under Part 91 but I'm not sure if the manufacturers recommendations override that?

 

Neither.

 

The PIC is responsible for determining airworthiness for the purpose of operating the aircraft. The owner/operator is responsible for maintaining the aircraft in an airworthy condition. The mechanic who performs the work is responsibile for determining that the work that's been done has been performed to an acceptable standard, and is airworthy, and it's the PIC who returns that work to service by operating the equipment, that actually fully returns it to an airworthy condition.

 

Being able to inspect the aircraft prior to flight and determine that the aircraft is airworthy (in compliance with type certification data and ammendments, and safe for flight) is not the same as deciding policy with regard to continuing airworthiness issues such as TBO. However, when deciding whether or not to fly an aircraft which is beyond TBO, one must decide if the aircraft is safe for flight. Therefore, while one can't set policy or determine policy as PIC, one must determine for the purposes of the duration of the flight, if the aircraft is safe to fly. One needs to ask how one does that when operating beyond TBO.

 

In practice, you don't take compression tests or spectrometric oil analysis before every flight. You probably don't check every component time or log signature before every flight. If you're in a "young" aircraft, you may have the comfort of knowing that many of the limits are far off, and haven't arrived yet. Once past limits or recommendations, that comfort space may slowly (or quickly erode), and you're left saddled with the presumption of what's safe and what's not. It may boil down to how much liability you want to accept based on your comfort level, and only you can decide that. It's incorrect to say, however, that the PIC is the one who determines aircraft airworthiness. The PIC determines if he or she believes the aircraft is airworthy and in an acceptable condition for flight, but airworthiness is a function of a much larger standard that encompasses mechanic and owner responsibilities, and ultimately the issue does rest with the owner/operator.

[cburg]

As long as you replace the parts listed in the airworthiness limitations section of the maintenance manual, the ship is airworthy. See:

 

http://www.faa.gov/about/office_org/headquarters_offices/agc/pol_adjudication/agc200/interpretations/data/interps/2011/MacMillan.pdf

Anybody with a current link?