Engine On Condition

[CitationJet]

I am getting within 200 hours of needing a major overhaul of the O-300 in my 172H used for private ops.

The engine is running very well, burning little oil, making rated power, good compressions etc, so I am loath to spend $20,000 pulling it apart simply because it has hit the magic 1,800 hour mark.

I know that the engine can run 'on-condition' beyond TBO however what are the practicalities of getting a LAME to sign off an annual inspection with an engine past TBO?

How long will a LAME continue to sign off a timex engine, 10% 20% beyond TBO, or indefinately while the engine is running well?

Where do I really stand on 'on-condition' operations?

I am aware of the Mike Busch experience in the US with running his C310 to 800 hours past TBO however he is an AI and can sign out his own engines. What can I expect here in Australia?

[VH-XXX]

LAME's here will definitely do it, however it can be luck of the draw as some of them won't be prepared to "help" you out.

In theory, provided that compressions are good and there's no metal in the oil filter and you have a good working relationship with your LAME, then things will definitely be in your favour.

[BrokenConrod]

Start saving your schekles!

My understanding is that "on condition" is history under the new CASA policies.

Some LAMEs have long refused to be a part of it anyway because of the unknown insurance liability.

BC :}

[bentleg]

The LAME we deal with has extended from 2000 out to 2200 "on condition" on a O320 in a 172P. The subject engine having had two new cylinders at around 1500 hours. It all came to an end when metal appeared in the oil filter at an oil change. "On condition" is at best borrowed time - not to be relied on. Go for it, but have your cheque book ready.

[jamsquat]

Talk to your LAME and find out what he's views are for "on condition" engines. When allowing for an engine to continue past TBO, many factors can contribute to the decision. How long since the engine was O/H? If its longer than 12 years then the engine is already "on condition" as far as the manufacturers concerned. Has the engine been topped recently? Bulkstripped since last O/H?
Generally if its running strong, making static RPM, Not burning oil or fouling plugs and theres no excess metal in the filter then it shouldn't be a problem for most LAMES to sign it out


JS:ok:

[MaxHelixAngle]

This may help;
Lycoming Flyer Key Reprints (http://http://www.lycoming.com/support/tips-advice/key-reprints/pdfs/Key%20General.pdf) (refer to page 3; Determining Engine Condition Of High Time - Piston Powerplants)

MHA

[CitationJet]

Thanks for the replies so far.

Can anybody outline their specific experiences in running beyond TBO - and advise which LAMEs in the Melbourne area have been agreeable to sign out a healthy but timex engine?

[Capt Wally]

'BC' good point. You see quite a few A/C these days 4 sale with engines either on condition or very close to becoming that. I wonder whether this is a refelction of what CASA are proposing to do by way of scraping the on condition allowance & the current owners are bailing out 'cause having on condition was the only way they could afford to keep their plane?
Just a thought as I have been seeking for some time now to but a plane & have found an ever increasin number being offered for sale as above.

I'd love a dollar for evey plane that is far far away from reg service centres say in the deep outback that has perhaps run a 'little' over the TBO anyway!:)

More to come am sure.


CW

[Bob Murphie]

This may sound simplistic and being one who would not normally suggest it, perhaps ring CASA? I did and was surprised by the candid and accurate answers to my questions regarding engines on condition and what CASA may or may not do in the future. I have forgotten his name, but he took over from Les Lyon who was the engine GURU. Airworthiness I think was the branch.

[jamsquat]

CJ, What Airport are you based at or near too? I may be able to reccomend someone close by.Also I wouldn't be too worried about CASA scrapping AD/ENG/4 just yet. Rumours about the CASA regs being rewritten have been flying around for years. I think they came to relise that on a world scale, our system is hard to beat.

JS:ok:

[CitationJet]

Thanks JS.

I am out of Moorabbin.

[Jabawocky]

Well Bob,

Why not share your new found knowlege.

And no I have nothing to gain from on condition, well not at least for another 2000 hrs or 8 years!

J:ok:

[jamsquat]

CJ, Give The Aviation Centre at YMMBa call or seeing that your based there just go in and have a chat. They also have a base at Tyabb with an engine O/H facility. I think they should be able to help you work out what your options are.

JS:ok:

[Bob Murphie]

Jabawocky;

jamsquat pretty well hit the nail on the head from my interpretation of the conversation. I didn't post the suggestion to enter into a debate on the why's and whichforsuchly's, but why dont you just do what I did and ring the bloke. He is a rather nice and informative member of a mob who I would not normally resort to for such information. AOPA want it scrapped I understand.

AD-ENG 4 is not part of any schedule of maintenance that I can gather, but is separate to. That is, given certain notation has been made on the MR and oil uptake etc have been monitored.

I would suggest that AD-ENG 4 will not be scrapped, but it may be modified in any rewrite of the regs so that it would be incorporated into the schedule of maintenance, whatever that may be.

In the meantime, it is a valid and useful piece of regulation.

[CitationJet]

Thanks Bob

My interest was not so much about what CASA means by AD/ENG4 as how LAMEs will actually apply it.