Factory built with Rotax Engine TBO

[ave8rr]

On page 12 of the Oct issue of Sport Pilot, there is a letter to the Editor asking a question re Rotax engines in Certified (24 etc) aircraft and IF these engines can be run "on Condition" after exceeding the TBO or calendar time when operating in the private category i.e. not being used in a flying school etc. There was no comment at the end to the question. Is what the submitter saying correct???

 

I know that in GA once the engine exceeds TBO or calendar time then the aircraft must be used for "private" ops only.

 

 

[Downunder]

Not having a crack at you Ave8rr but just for those that that may read this and get the wrong impression, LSA (24 rego) RAA aircraft are not "certified" in the common aircraft sense. LSA manufacturers can build to any standards they want or no standards at all.

 

There are probably many "19" rego aircraft bulit to a far higher quality than some factory LSA's.

 

On a similar note to your question is whether maintenance can be done on a 24 aicraft by the owner (L1) if used for private purposes. The answer is yes, but must be inspected and signed off by a L2 if put online.

 

 

[ave8rr]

Spoke with RAAus today and this topic is currently being discussed. A statement will be made soon hence no comment in Sport Pilot Mag.

 

 

[Jabiru Phil]

On a similar note to your question is whether maintenance can be done on a 24 aicraft by the owner (L1) if used for private purposes. The answer is yes, but must be inspected and signed off by a L2 if put online.

 

I am a tad confused here. My log book statement says.....Aircraft time in service between inspection by an authorised person

 

100 hours or 12 months

 

Whichever is the earliest

 

I have assumed in the past that an authorised person is a lame 2 or better, not me.

 

I have always done the normal 25 hour service as per the jab maintenance schedule and the 100 hourly or 12 monthly by a Lame 2

 

I have felt very comfortable with this procedure.

 

Have I got the interpretation wrong? (Private use only)

 

Phil

 

 

[ave8rr]

Bert Flood advise that...

 

Rotax do NOT have an “on condition” operating schedule.

 

They also advise that crankshafts are NO longer available for the 618 engine so cannot be overhauled.

 

Attached is a file from Rotax giving TBO / Calendar time for the 912 series engines.

 

I assume from this that once an engine reaches the TBO or calendar time then the engine is to be overhauled???

 

SB Rotax 912-057-UL.pdf

 

SB Rotax 912-057-UL.pdf

 

SB Rotax 912-057-UL.pdf

[Guest nunans]

It will be interesting for sure, If they rule no private use for 24-, 25-, aircraft if the engine is not in calender or hours then it will mean alot of grounded low hour planes around.

 

I understand that only some prefix aircraft, (not 10 or 19 or 28) can be used for training and then only if L2 or lame maintained and engine in hours/calender etc.

 

if a 24,25, or 55 is not being used for training then what's the problem with an out of hours engine? a 19 can be flown while out of hours and maintained by the untrained owner within his or her capabilities whatever they may be, so I don't see the need to be strict on a 24 reg private use aircraft? how does being factory built make it more dangerous?

 

If the 24 rego aircraft which has been L1 maintained and has the out of hours/calender engine is to be used for training or hire then simple, put a new engine in it and get an L2 or Lame to inspect/maintain it and away you go..

 

You see so many old aircraft in the members market with <500hr engine and airframe but you know the engines would be out of calender so grounding them would be a big waste when they can still be flown for years privately with the exissting engine.

 

 

[DonRamsay]

While I have heard of Rotax 912 engines running to 3,000+ hours "on condition" I wonder how they routinely assess the condition of the crankshaft. As I understand it 912 crankshafts are the first thing in the bin during a TBO overhaul. It was the crankshaft that failed in the double fatality in the Sting near Goulburn in the last decade. Compression test is, of course, not going to show up a failing crankshaft.

 

 

[Yuri Gagarin]

While I have heard of Rotax 912 engines running to 3,000+ hours "on condition" I wonder how they routinely assess the condition of the crankshaft. As I understand it 912 crankshafts are the first thing in the bin during a TBO overhaul. It was the crankshaft that failed in the double fatality in the Sting near Goulburn in the last decade. Compression test is, of course, not going to show up a failing crankshaft.

They can do that if you don't put the oil cap back on and keep flying even though you know something is wrong.

 

The pilots caused the engine to fail.

 

 

[Guest nunans]

I imagine they don't assess the crank shaft, they just live in an open area and fly the forced landing when it evenually stops or buy another engine when the compression gets low and they start burning oil.

 

The bulk of the aircraft affected by this decision won't be 3000hr engines they will be calender expired engines with 425hr on them.

 

 

[Downunder]

Is there a history of time expired, well maintained engines failing?

 

Perhaps "in" time engines poorly maintained are a larger problem.

 

 

[68volksy]

They can do that if you don't put the oil cap back on and keep flying even though you know something is wrong.The pilots caused the engine to fail.

Read the coroners report Yuri - it was the treatment of the engine by the aircraft's previous owner that seems the most likely cause of the crankshaft failure.

 

 

[Yuri Gagarin]

Read the coroners report Yuri - it was the treatment of the engine by the aircraft's previous owner that seems the most likely cause of the crankshaft failure.

And we know that the coroner is always right don't we.

 

I have been to a coroners inquest and how he came to his findings amazed me,

 

(Australian is not my first language)

 

 

[Guest Andys@coffs]

Please, lets not revisit the sting accident. There have been pages and pages of comments on this forum over the years and at this point in time there isn't anything new to be added.

 

It is standard overhaul practise to replace the crank and as such we have to assume there is a basis for its replacement other than "it seemed like a good idea at the time we were writing the overhaul instructions...." A couple of the reasons might well be that spare parts sales are very profitable to the company, and in mandating crank replacement there are a lot of associated spares that need to be replaced while at the same time they address a potential liability hole by forcing complete disassembly and complete reassembly...." It matters little what their drivers are, that they mandate its replacement is all that matters IMHO. We are allowed to maintain 24 registered aircraft either ourselves (as L1's) or via a L2 or better if its on line, I don't see that there is a great deal of scope to argue that we have to maintain the aircraft as per the manual without deviation but the engine is perfectly Ok to deviate from....

 

That said, its not black and white to some and as such the RAAus team are seeking clarity

 

Andy.

 

P.S these are my personal opinions, and are nothing to do with my board position and certainly don't, as far as I know, represent the RAAus view at the time I write this.

 

 

[facthunter]

ALL crankshafts have a definite life, as well as a lot of other parts that is not determined by wear. Cracks due fatigue are common. The 912 is a built up (pressed) crank which may have a bearing on it.(No pun intended but A good one). Nev

 

 

[Downunder]

Maybe a "middle of the road" solution is to make time or hour expired (engined) 24rego aircraft into E24 rego.

 

 

[facthunter]

I have been told that some engines that have run extra hours over TBO are not in very good shape and may have more than normal money spent on them to get them back to tolerance. It makes sense that might happen. Nev

 

 

[Guest nunans]

24. (25 or 55 too for that matter)rego that's not being used for training or hire should have NO additional maintenance requirements to 19 rego!

 

Is every 19 class L1 maintained aircraft grounded on the day the calender or hours runs out? No, there's no audit process or training it's "up to you to maintain it properly, your responsibility, and to exercise this right you must comply to the limits imposed (weight, pax, no unsuspecting students or hiring customers).

 

Raa has already got it right, the waters were just muddied by floods saying there is no "on condition" for rotax engines. Which is fine, the 19 regos and private use 24, 25etc don't need on condition schedules, if you need it maintained by a responsible person (ie an L2 or lame because you are training or hiring) then buy a new engine. If you don't need it maintained by a responsible person and you can do it yourself (L1 due to private use only) then you decide when you need a new engine.

 

As for the must maintain the airframe so why not the motor, this is just it I think the maintenance requirement for engine and airframe are the same depending on use. Either on line so L2 or higher for both airframe and engine or private use L1 for airframe and engine.

 

 

[Guest nunans]

I have been told that some engines that have run extra hours over TBO are not in very good shape and may have more than normal money spent on them to get them back to tolerance. It makes sense that might happen. Nev

Rotax 912 engines at least, aren't brought back to tolerance when they exceed tbo they are sold to 19 reg aircraft or scrapped. A full overhaul is dearer than a new engine

 

 

[facthunter]

That is a consideration too. If it is going in the bin it has no residual value of any ,magnitude.. That is pretty much the case with small diesel engines sourced from cars. As labour costs rise , the new engine almost always becomes the preferred option If you have a vintage aircraft you are a special case. Nev

 

 

[Guest Andys@coffs]

As for the must maintain the airframe so why not the motor, this is just it I think the maintenance requirement for engine and airframe are the same depending on use. Either on line so L2 or higher for both airframe and engine or private use L1 for airframe and engine.

Can you show me anything that says its Ok to deviate from manufacturers maintenance instructions with regard the airframe for 24 registered.....As I understood it you maintain as per the EOM guidance or at that point it becomes non conforming and E24.

 

As I own a 19 I'm not as up to speed on 24 as 24 owners would be, but I was pretty sure my understanding was correct, in which case maintenance by L1 or L2 becomes moot as long as they can both follow the OEM's instructions.

 

I also sort of understood that the change from 24 to E24 was to all intents and practical purposes one way, you cant return to 24.....or have I got that wrong

 

Andy

 

Andy

 

 

[Guest nunans]

Can you show me anything that says its Ok to deviate from manufacturers maintenance instructions with regard the airframe for 24 registered

The fact that 24 rego can be L1 maintained when not on line leaves it open to deviate through lack of regulation, responsibility and audit of the L1 maintenance. the same way it does for 19 and 10 rego. That's why the L1 maintained aircraft wear the big yellow sticker that says "made of matchsticks bla bla bla"

 

The line in the sand for maintenance is around use not rego prefix.

 

 

[Guest Andys@coffs]

Well......we'll just have the wait and see which way it goes....

 

 

[johnm]

so there is a unlikely possibility ! that owners (particularly private use) could be told to throw a 912 away if it reaches TBO ?

 

a much more expensive motor if you don't use the hours ? .............. is that's what being said here ?

 

 

[facthunter]

Surely a school aircraft would use the hours before it was time expired. They often sit well. An unworn engine would probably only need seals and gaskets or if you are fussy a set of rings and exhaust valves, and run out the engine hours left. Nev

 

 

[johnm]

yes school aircraft should get inside TBO parameters easy - you'd think

 

I am just thinking about mountains of private use 912 engines - piles & piles of them because they never got enough hours on them but they got to the 12 or 15 year time limit - what fate is in store here ?