Replace the engine?

[tb10er]

Our engine is approx 2000 hours old so we now have to make the decision how to proceed. We are a privately run group (a ltd company) who "hire" the aircraft back to ourselves, the members. Occassionally, ad-hoc training for IMC, re-validation will take place for members only. The aircraft is maintained by a reputable company, but of course, they are out to make as much money as possible out of us.

My question is this:

If the aircraft is owned privately and only flown by the owners, does the 2000 hours (or whatever) apply providing that it passes compression checks, etc? Therefore we can carry on flying for as long as we feel comfortable, or it fails the checks.

Or, as we are "hiring" it to ourselves, do we have to replace it now, or after the 20% extension has expired.

Many thanks

[gyrotyro]

I believe that you can continue to fly the aircraft "on condition" as long as the compressions at each 100 hour or annual inspection continue to be ok. even then you still have the choice to change the offending cylinder and then keep going. The choice is yours.

[robin]

My understanding is that if the aircraft is being operated as a company, then public transport rules apply, but I might be thinking of non-equity ownership.

But I guess others with more knowledge will correct me.

[peterh337]

Operating as a ltd company is IMHO not relevant, but renting is.

I was on G-reg 2002-2005. The plane was ltd company owned and the company (which I owned 100%) rented the plane (a) to myself, and (b) to a few others.

Back then the regs clearly required Public Transport CofA maintenance for renting out.

My view is that (a) alone is the same thing. But it's a grey area in practice; many private owners own the plane via a company and get the company to invoice them for flying (which is a standard component in the defence against Benefit in Kind, which always arises on a ltd company owned plane) yet they run the engine "on condition" etc. But what is "renting"? If the owner didn't generate that "rental invoice" but just flew the plane whenever he wanted to and got an equivalent adjustment done via the Director's loan account at the end of the financial year, that clearly isn't "renting" then.

IMHO, in the scenario described i.e. multiple pilots, if the plane is "rented" then you have to overhaul.

I would overhaul anyway at 2k. I know of the standard arguments against taking apart a "working" engine but you never know what is brewing inside... if (like most) you don't do oil analysis then you have very little idea of the internal condition.

If you were N-reg then you could rent a plane out while maintaining under FAR Part 91, with no special requirements. There is a potential 100hr check but this is required only for paying passengers, and if you train others in your plane.

[A and C]

As said above the hire status of this aircraft puts it into a grey area legally however it can be operated until you reach 2000 hours + 20% or 12 years +20%.

Pushing aircraft past the 20% mark is not usually economic in the long run (standby for the person who as done 10,000 hours without touching their O-320!) so have the money at the ready to do the overhaul before the 20% mark is reached if a lot of work is required to keep the engine running.

When overhaul time comes there are only three companies in the UK who are worth using in terms of quality of work, price & after sales service, a quick search on these pages will find you the best ( not the cheapest) deal.

[peterh337]

This may be obvious but the money saved by running past 2k hrs is very small.

Say the overhaul is £20k - a gold plated money-no-object job done in the USA by the best engine shop and with DHL shipping both ways - that is £10/hr on the engine fund.

If you run the engine to 3k hrs, the fund reduces to £6.66/hr i.e. a saving of just £3.33/hr.

Put this against the cost of avgas of (very) roughly £80/hr...

If you have a CS prop then your prop fund will be a few quid per hr also...

Also, an engine run to 3k is obviously more likely to need more bits changed than one that was run to 2k hrs.

The only company in the UK which I would recommend on the basis of reports from people I know personally is Nicholson McLaren.

[jxk]

Two points to consider:

The compression test, especially on Lycoming engines, doesn't give any indication of cam wear etc. Make sure your maintenance organisation do a proper analysis of the oil filters.

If you do run the engine too long it may affect the exchange (core) value because things like crankcases tend to chaff and wear.

[A and C]

JXK makes a very good point about crankcase fretting, if you have oil leaks from the crankcase joint and the cylinder bases the chances are the crankcase has fretted.

To continue to run an engine if this is happening will write off the crankcases and so cost far more money than you save from continuing to run the engine.

The engine shop that Peter recommends above is one of the three in the UK I would recomend.......... And my personal choice of engine shop.

[Mickey Kaye]

A and C

Are you happy to PM me the other two?

[A and C]

Eisenburg at Southend and AEP.

Divco are very good but if you let the fretting get to bad even they can't repair the cases.

[englishal]

I'd also recommend Nicholson M, and we had our engine zero timed a few years ago by them. Not the cheapest, but cheapest is NOT always best when it comes to engine rebuilds, but they were fantastic.

We had to have our crank case sent to the USA for machining due to fretting (in which case it might have been better to use Peter's US shop but we didn't know this before the work started), so if we'd continued to run no doubt it would have got worse. We actually rebuilt 100 hrs before TBO as we'd just acquired the aeroplane and wanted to make sure we had a known quantity.

[extreme123]

First time posting here, but been a regular follower for several years, and flying for many more....
Having tried the majority of "reputable" engine shops around the UK on numerous occassions for everything from advise to engine overhauls, with varing degrees of satisfaction, or rather dissatisfaction.....
I was refered to a newish engine shop, AEP, by a regular contributor of this forum soon after he had his engine repaired by them.
An engine overhaul, several components and most recently a new kit engine from them, I can offer nothing but praise. Their advise, attention to detail and after sales service has been fantastic, definitely worth giving them a call.