I have been tilting windmills the last week. I have a customer due for a Phase V inspection soon and it is beyond recommended overhaul and up against recommended HSI interval.

The Citation 500 series resale market has been in the tank for some time. They were a great way to get around when fuel was two dollars a gallon and engine overhauls were in the $200K range. We know what the price of fuel is and second run overhauls often exceed $400K each. Many Citations that come into my shop for Phase inspections come with a caveat that if we find anything big (like a flat spotted tire) we will stop the inspection and they will part the aircraft out. Currently nice Barons are worth more the nice Citations that are close to having timed out engines.

At this time it appears there may be a window to continued operation of some of these aircraft. In the past it was well accepted that the engine overhaul for Part 91 operators was a RECOMMENDED interval per Pratt & Whitney"s SB7003. The HSI too was noted as a RECOMMENDED interval in that same publication. The document that dictated these inspection was not P&W's SB, it was Cessna's approved inspection program. The FAR's in Section 91.409 (f) state an operator of a turbine powered must select and identify an inspection program. Most Citation operators use Cessna's continuous airworthiness inspection program. Up until fairly recently this inspection program called out a Phase 25 this Phase mandated a Hot Section Inspection per P&W's SB7003 recommendation. Again this is a RECOMMENDED inspection per P&W but, since it was an inspection called for by Cessna in the Approved Inspection Program the operator was obliged to comply with the HSI as it was an inspection listed in this document.

Over the last couple years Cessna has eliminated the Phase 25 inspection requirement as the did not want to be troubled with keeping that data up to date in their manual. Now the only reference to these requirements in their manuals are in the Chapter 5 limitation section and it simply refers you to P&W SB7003 where the OH and HSI intervals are noted as RECOMMENDED. There are companies, Sierra Industries for one who have or are putting together approved programs to extend the engine intervals on these engines. With the deletion of the Phase 25 from Cessna's inspection program it is not clear this would be needed for a Part 91 operator.

The FAA recently introduced a document, an ADVISORY Circular, AC 120-113 that was intended to clarify the rule regarding engine time in service intervals. Unfortunately it does little to make this any clearer. Section 5.1 of this document states the engine manufacturer establishes the RECOMMENDED time in service interval. Keep in mind this document is ADVISORY only and is not a rule. It reminds me very much of an FAA INFO document that was published prior to the legal interpretation of the the word current with regard to inspection programs. The legal interpretation reversed the thoughts presented in the INFO document. I have a call into FAA AFS-300, Washington DC and have not had a return call. My guess this issue too may need a legal interpretation. This may take months or a year.

There is some precedent with regard to these recommended inspections with regard to multi-engine turbine powered aircraft. It has been generally accepted by most operators and FAA region that engine overhaul an propeller overhauls would not be an airworthiness limitation for Part 91 operators on turbo prop aircraft like the King Air or Piper Cheyenne. How can a Pratt & Whitney JT15D, also a multi-engine propulsion system recommendation be any different with interpretation of the rule?

I have asked Phil Pankratz, head of Cessna technical support, propulsion group for some clarity on whether they would return an aircraft to service after completing Phase 1-4 or Phase 5 inspections, Phil needed to go ask the service center group and the Wichita Service center stated they would not complete the RTS (return to service) on the engine portion of the inspection. To be fair, I did not get a chance to clarify the fact the the Phase 25 has been deleted in Cessna's program when I spoke to Phil last week. I also have contacted Pratt & Whitney to ask if they would complete an RTS for a HSI inspection if the engine was beyond recommended TBO, they would not. I spoke to other P&W DOF's Designated Overhaul Facilities that stated they would. I have discussed this with Paul Jones at Turbine Specialties and this is new ground to him as well.

I am not advocating that operators continue operation of these engines with out the recommended Hot Section Inspection as that is where the greatest area of failure is likely to occur on one of these engines. A careful review of the aircraft's specific engine records would be in order as completing an HSI on an engine that had cycle limited components due in the short term like HT DISC, impeller or even HT blades may not make it worth the investment. Conversely there are many aircraft that may have enough cycle life remaining to suggest the investment as it could add another 1800 hours of utility to and otherwise low worth aircraft.

I believe the Citation 500 right now is in a situation like the Cessna 425 was when faced with their SID inspections. With the legal interpretation of the rule, if an operator were to identify that their aircraft was on a CURRENT inspection program that does not call for a PHASE 25, that aircraft's engine overhaul and HSI requirement would only be dictated by the engine manufacturers RECOMMENDED intervals.

This is my take on this rule and I am still awaiting input from FAA DC and others.




Edited for spelin 1/16/17

But even if it is so, how do you get around 91.409?

(e) Large airplanes (to which part 125 is not applicable), turbojet multiengine airplanes, turbopropeller-powered multiengine airplanes, and turbine-powered rotorcraft. No person may operate a large airplane, turbojet multiengine airplane, turbopropeller-powered multiengine airplane, or turbine-powered rotorcraft unless the replacement times for life-limited parts specified in the aircraft specifications, type data sheets, or other documents approved by the Administrator are complied with and the airplane or turbine-powered rotorcraft, including the airframe, engines, propellers, rotors, appliances, survival equipment, and emergency equipment, is inspected in accordance with an inspection program selected under the provisions of paragraph (f) of this section, except that, the owner or operator of a turbine-powered rotorcraft may elect to use the inspection provisions of § 91.409(a), (b), (c), or (d) in lieu of an inspection option of § 91.409(f).

Adam,

The overhaul and HSI are not listed in Cessna's inspection program. There is no life limit mentioned in the TCD's for the engine or airframe. The operator can select the Cessna inspection program it no longer has a HSI inspection requirement and the overhaul is recommended. Again we are speaking of a the same Administrator that has stated that overhaul of multi-engine turbine propulsion systems (PT6 overhaul and propeller overhaul) are recommended and not required for Part 91 operation. How can the rule be different for the Citation another multi-engine turbine propulsion system who is effected by the same rule.

The language in the SB's, Inspection Documents and the AC are vague and well removed from the rule. I believe the rule needs to be clarified. Recommended like Current will need to be defined with regard to the rule.

The FAA has determined manufacturers can not make rule. They can put the work MANDATORY on all the document they want, it does not make it rule. If they put a word like RECOMMENDED on a document how does that become more enforceable. Pratt and Whitney reiterated the fact these are recommended intervals in their SIL GEN 034R3. The only thing it states in this document is if you exceed the recommended overhaul or HSI interval you will not be covered under any of Pratt & Whitney's warranty programs. It will be up to the Local Airworthiness Authorities approval. Again if a King Air is not required to comply why a Citation?

Not right on point but worth mentioning is that Richard Bacon has gotten several FSDOs to agree in letters that phase inspections can be extended for low use birds that meet other conditions.

As far as folks not returning a plane to service if engine is past TBO, I don't understand on what grounds they can do that. I simply wouldn't use them. Several part 91 folks are flying turbines past TBO but don't exceed part life limitations and still do hot sections. This has been debated in detail on here and other places.

Of course, there are inspection programs such as M.O.R.E that specifically allow going beyond recommended TBO.

This is interesting, very much so.

So does a King Air owner part 91 NOT have to comply with the gear/prop overhaul intervals?

Those are mandatory inspections. TBO is recommended. However, Bacon was working on extending the time between inspectors for low use birds.

The gear assuming you are using the Beech inspection protocol is mandated by them as being required. The propellers have been less clear cut as the propeller manufacturer calls it a recommended overhaul. The FAA 25 years ago varied from region to region on the propeller issue. Most now agree recommended means recommended for part 91 operators. Certificate holders, 121 and 135 the requirement is often dictated by their specific operating specifications.

Please PM me next time one of those shows up!

Overhauls are NEVER mandatory (unless directed by AD).

Inspections are mandatory.

If a document contains both inspection and overhaul parts, only the inspection part needs to be complied with to be in compliance with the reg.

Manufacturers are getting wiser to this. That is why Williams engines don't have an overhaul, they get a "major periodic inspection". Williams in effect renamed the overhaul to an inspection on the premise that what you call it changes the legal imperative.

Manufacturers will continue to manipulate their "rule making" poe3wr under 91.409(e)/(f) until the FAA gets off their fat ass and fixes things so that owners have rights.

Mike C.

Mike,

Can you help me with the rule that dictates inspections are mandatory?

The FAA was quite clear in their legal interpretation of Cessna's attempt to mandate inspections via maintenance manual revision with their clarification of the word current with regard to these inspections.

I certainly may have missed something in the rule that suggest this. Again I have not advocated forgoing the HSI on the JT15D, though I am not aware of the rule making inspections mandatory that are not called out in the specific aircraft inspection program selected by the Part 91 operator of a multi engine turbine aircraft.

FAR 91.409(e).

No person may operate a large airplane, turbojet multiengine airplane, turbopropeller-powered multiengine airplane, or turbine-powered rotorcraft unless ... the airplane or turbine-powered rotorcraft, including the airframe, engines, propellers, rotors, appliances, survival equipment, and emergency equipment, is inspected in accordance with an inspection program selected under the provisions of paragraph (f) of this section

You must inspect according to an inspection program. It the program you select says something must be inspected, then it must be inspected.

Note, however, that if the program says "overhaul", which means rebuilding an item, that part of the program is not binding. You have to inspect, check for airworthiness, not overhaul, restore life to a part.


No, they weren't clear at all, IMO.

First you have the chief counsel opining that Cessna cannot force existing owners to adopt new inspection requirements.

Then you got the AFS-300 folks saying, hang on, but each new owner has to select the "current" program.

But then there is no precise definition of what is an "owner". If you buy an LLC holding an airplane, does the airplane become unairworthy?

And they didn't specify what happens when a new owner buys an airplane. Presumably it becomes unairworthy on the spot. So how does one make it airworthy again?

The FAA has muddled this up tremendously. The root problem is that 91.409(e/f) is just a bad reg because it fundamentally violates the APA which prohibits manufacturers from making rule. There's nothing in the APA that clarifies manufacturers can make rules if they only affect FUTURE persons, and further, changes in the programs affect CURRENT owners in that they can damage the aircraft market value substantially. So the whole thing is just wrong. No airplane should become unairworthy just because the OWNER changes.


Well, there is an interpretation aspect here for 91.409(f):

The registered owner or operator of each airplane or turbine-powered rotorcraft described in paragraph (e) of this section must select, identify in the aircraft maintenance records, and use one of the following programs for the inspection of the aircraft:
...
(3) A current inspection program recommended by the manufacturer.
Is "manufacturer" only the airframe maker, or does each piece get its own program, say engine gets its own engine program from Pratt?

I think it is the airframe maker. So the argument is if the aircraft maker leaves out engine HSI in their program, then you are not obligated to do it.

Mike C.

IMO, once the aircraft gets to this point it is worthless to all except the current owner who may be able to wring more hours out of it.

Mike,

I think we just came to the same conclusion. We now get back to what is the meaning of Recommended. Recommended inspection, what does recommended mean with regard to the rule?

Erwin,

If a part 91 operator sells to another 91 operator that can operate the aircraft for as much as another 1800 hours or more I would assume this would add value to an airframe that is currently deemed financially unusable. The aircraft I am questioning has one engine due HSI, that engine has 5000 cycles remaining on the highest time part. For many operators they could be on soft food before hitting the life limit on any engine component. The current market value may not justify the cost of overhaul, it may support HSI cost. If it can just be run as is with the HSI completed on condition there is no doubt this adds value to the aircraft.

Finally received a call from Marcus Cunningham, FAA AFS-300 Washington, DC. He agreed that per the Rule a Part 91 operator on the current Cessna continuous inspection program, engine overhaul and HSI would only be recommendations.
The engines would only be limited by component life limit. His office will be working on some new guidance on this as he admits it has not been clear.

Again, I would still recommend HSI at listed interval or something close to that and also review engine records to make sure the specific engine is not approaching life limit on any component. If not this could add a lot of utility to airplanes that currently have a very low market value as all assumed the recommended engine limitations were gospel.