Cost to overhaul a 912?

H. Paul Shuch is a Light Sport Repairman with Maintenance ratings for airplanes, gliders, weight shift control, and powered parachutes, as well as an independent Rotax Maintenance Technician at the Heavy Maintenance level. He holds a PhD in Air Transportation Engineering from the University of California, and serves as Director of Maintenance for AvSport of Lock Haven.

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drseti
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Re: Cost to overhaul a 912?

Postby drseti » Mon May 23, 2016 4:33 pm

designrs wrote:I was thinking to sell the TBO motor at 2,000 hours for $9k to an experimental builder or operator.
Does that seem easily doable?


You can sell them on eBay, but I think the going price is quite a bit less. I know many commercial operators who swap engines at mid-TBO, and then sell the old engine for $10k or so.
The opinions posted are those of one CFI, and do not necessarily represent the FAA or its lawyers.
Prof. H. Paul Shuch, Ph.D., CFII, LSRM-A/GL/WS/PPC, iRMT
AvSport of Lock Haven
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designrs
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Re: Cost to overhaul a 912?

Postby designrs » Mon May 23, 2016 5:06 pm

$3k at 2,000 hours?

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Re: Cost to overhaul a 912?

Postby drseti » Mon May 23, 2016 6:00 pm

That's probably more realistic
The opinions posted are those of one CFI, and do not necessarily represent the FAA or its lawyers.
Prof. H. Paul Shuch, Ph.D., CFII, LSRM-A/GL/WS/PPC, iRMT
AvSport of Lock Haven
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Re: Cost to overhaul a 912?

Postby designrs » Mon May 23, 2016 7:47 pm

So Lockwood sells the new motor for $17,700
Estimated cost to remove and box old motor & install new motor?

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Re: Cost to overhaul a 912?

Postby drseti » Mon May 23, 2016 7:58 pm

That should run a couple k, bringing you up to my estimated 20.
The opinions posted are those of one CFI, and do not necessarily represent the FAA or its lawyers.
Prof. H. Paul Shuch, Ph.D., CFII, LSRM-A/GL/WS/PPC, iRMT
AvSport of Lock Haven
fly@AvSport.org
http://AvSport.org
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Re: Cost to overhaul a 912?

Postby designrs » Mon May 23, 2016 8:06 pm

Thanks much!

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Re: Cost to overhaul a 912?

Postby drseti » Tue May 24, 2016 9:47 am

I imagine if you ring up Lockwood, they can quote you a turnkey job.
The opinions posted are those of one CFI, and do not necessarily represent the FAA or its lawyers.
Prof. H. Paul Shuch, Ph.D., CFII, LSRM-A/GL/WS/PPC, iRMT
AvSport of Lock Haven
fly@AvSport.org
http://AvSport.org
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Re: Cost to overhaul a 912?

Postby dstclair » Tue May 24, 2016 9:54 am

Out of curiosity, why replace your engine at 2000 hrs?
dave

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Re: Cost to overhaul a 912?

Postby drseti » Tue May 24, 2016 10:40 am

dstclair wrote:Out of curiosity, why replace your engine at 2000 hrs?


Dave, that's probably an excellent topic for its own thread, but I'll start with a response here.

Traditionally, TBO has always been advisory, not regulatory. An engine was replaced or rebuilt on condition. One keeps tabs of oil consumption, cylinder compression history, oil spectrographic analysis results, and perhaps frequent borescope inspections as the engine approaches TBO, and then makes an informed decision as to whether the engine is likely to fail between now and the next condition inspection. It's a gamble, but most people win at this game.

Initally, the SLSA universe followed the same replace-on-condition attitude. Then, engine and airframe manufacturers started writing life limits into their maintenance manuals and operating instructions. It was controversial whether these limits could be enforced, so somebody asked FAA Legal Dep't for a letter of interpretation.

<rant>BIG MISTAKE! Never ask FAA for an opinion if there's a chance you won't like their answer!</rant>

So, here's what FAA published. In a letter dated July 10, 2015 to Terrence K. Keller, Jr., Lorelei A. Peter, FAA Assistant Chief Counsel, Regulations Division, stated:

The aircraft would not be airworthy if operated beyond TBO or outside the manufacturerʹs specified life limits.


Pretty clear, no? But this is in direct contradiction with an earlier letter from the same Ms. Peter dated August 21, 2013 to Charles Willette of Dodge Center Aviation, LLC, in which she stated:

The intervals specified in maintenance manuals for S‐LSA, therefore, are not per se mandatory. Consequently, a maintenance provider may develop an alternative that is acceptable to the FAA and maintain an S‐LSA in accordance with those provisions.


Waters now muddied!

The most conservative course of action would be to assume that the more recent interpretation takes precedence over the earlier one. But our friend, master mechanic Mike Busch of Savvy Aircraft Maintenance, has recently asked for clarification. In a letter to that same FAA attorney, he wrote:

Clearly Willette and Keller cannot both be correct. I am requesting a definitive interpretation of
which of these two interpretations the owner or operator of an S‐LSA may rely upon.
These contradictory interpretations have created considerable confusion in the S‐LSA
community. In the past, this confusion has been largely academic because up until now few SLSAs
have been in service long enough for TBO to be an issue. However, a definitive resolution
of this question has now become time‐critical, because it is now 12 years since the S‐LSA rule
was adopted in 2004, and roughly 80% of the S‐LSA fleet is powered by Rotax 900‐series
engines for which the published TBO is 12 calendar years or 2,000 hours, whichever comes first.


Don't hold your breath for an answer from FAA, but if your engine is approaching 2000 (or whatever its published TBO is), you might consider an engine replacement. Especially if your plane is in commercial service, where lawsuits and liability issues are pervasive.
The opinions posted are those of one CFI, and do not necessarily represent the FAA or its lawyers.
Prof. H. Paul Shuch, Ph.D., CFII, LSRM-A/GL/WS/PPC, iRMT
AvSport of Lock Haven
fly@AvSport.org
http://AvSport.org
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Re: Cost to overhaul a 912?

Postby dstclair » Tue May 24, 2016 11:00 am

Paul,

I think you missed a key point in the Keller letter:
An aircraft that is
operated after components have exceeded life limits specified in the manufacturer's maintenance
manual or other procedures developed by a person acceptable to the FAA would not comply with
§ 21.181.
Bold added by me. This statement also puts this letter in line with the Willette opinion.

Other procedures acceptable by the FAA do include on condition, I believe.
dave

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Re: Cost to overhaul a 912?

Postby drseti » Tue May 24, 2016 11:34 am

dstclair wrote:Other procedures acceptable by the FAA do include on condition, I believe.


Yes, but only if FAA specifically says so, in writing. I can't find anywhere that they have, except as it pertains to approved progressive inspection programs. That's probably why Mike requested clarification.
The opinions posted are those of one CFI, and do not necessarily represent the FAA or its lawyers.
Prof. H. Paul Shuch, Ph.D., CFII, LSRM-A/GL/WS/PPC, iRMT
AvSport of Lock Haven
fly@AvSport.org
http://AvSport.org
http://facebook.com/SportFlying

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Re: Cost to overhaul a 912?

Postby drseti » Tue May 24, 2016 11:38 am

And BTW, exactly who is a "person acceptable to the FAA"?
The opinions posted are those of one CFI, and do not necessarily represent the FAA or its lawyers.
Prof. H. Paul Shuch, Ph.D., CFII, LSRM-A/GL/WS/PPC, iRMT
AvSport of Lock Haven
fly@AvSport.org
http://AvSport.org
http://facebook.com/SportFlying

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Re: Cost to overhaul a 912?

Postby MrMorden » Tue May 24, 2016 11:46 am

drseti wrote:And BTW, exactly who is a "person acceptable to the FAA"?


I'm barely acceptable to my wife and friends, no way the FAA would find me acceptable. :lol:
Andy Walker
Athens, GA
Sport Pilot ASEL, LSRI
2007 Flight Design CTSW E-LSA


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