New Lyco crank AD

[peterh337]

I've just received (by email; the FAA notification service) a new AD on these cranks.

It looks like the original AD (which resulted from SB569A (http://www.peter2000.co.uk/aviation/engine-rebuild/index.html)) but I queried it with a US engine shop and apparently they have expanded it to some new serial numbers.

SUMMARY: We are superseding an existing airworthiness directive (AD) for certain Lycoming Engines (L)O-360, (L)IO-360, AEIO-360, O-540, IO-540, AEIO-540, (L)TIO-540, IO-580, and IO- 720 series reciprocating engines. That AD currently requires replacing certain crankshafts in the affected engines. This AD continues to require replacing certain crankshafts, corrects the start date of affected engine models in Lycoming Mandatory Service Bulletin (MSB) No. 569A to the start date in Supplement No. 1 to Lycoming MSB No. 569A, dated May 27, 2009, and includes additional (formerly experimental) IO-390, AEIO-390, and AEIO-580 series engine models having affected crankshafts. This AD was prompted by Lycoming Engines discovering that the start date of affected engine models in MSB No. 569A is incorrect and the need to include additional engine models having the affected crankshafts. We are issuing this AD to prevent failure of the crankshaft, which will result in total engine power loss, in-flight engine failure, and possible loss of the aircraft.

2012-19-01 Lycoming Engines: Amendment 39-17196; Docket No. FAA-2006-24785; Directorate
Identifier 2006-NE-20-AD.

I will try to add the PDF to the end of my writeup, today. It should be online somewhere, however.

Edit: AD PDF added.

[AdamFrisch]

Are they pulling a "Hartzell maneuver", or is there genuine problems here?

[Katamarino]

How does this work. I assume that the problem is due to a defect in design or manufacturing; but I also assume that it's up to the owner to pay for correcting Lycoming's mistake?

[peterh337]

When I researched this topic in 2008 (for my writeup) it turned out to be complex.

From vague memory:

Lyco (or their crank subcontractor) made a number of distinct "errors".

One was leaving out a stage in the heat treatment. This produced cranks which cracked after tens of hours, or less, and some people got killed. This was the original AD.

Then there was the addition of vanadium, which was authorised by Lyco, or not... there was a lawsuit between Lyco and the contractor which I believe Lyco lost i.e. they did authorise the addition. But there is no apparent reason why vanadium should make the cranks break...

The lawyers and the FAA got stuck into it and decided that putting a 12 year life on the cranks (which is the official life of the whole engine, anyway) is the way to deal with it.

But AFAIK there was never an engineering reason for the 12 year life limit.

So this latest thing is probably a dud, but being an AD you have to comply with it.

It is distasteful to make owners pay for it. Lyco's $2k crank offer (which I used myself) expired in 2009. If they had the slightest bit of honour they would re-open that offer to owners of the new serial numbers.

[BabyBear]

Being in the process of investigating the feasibility of purchasing an aircraft with an O-360 I would be very interested in cross checking the serial number.

Can you point me in the direction of the published list please?

BB

[Barcli]

Peter,
I can see that MSB569A has been re-issued because Lycoming feel more engines are affected. I can see that they have a compliance start date of October 24th 2012..... but I cannot see any difference to the serial number list that accompanies MSB569A - or is there a new list somewhere ?
Scared......

[peterh337]

BB - you need to find the new SB.

B - I would contact Lyco.

I have always felt that Lyco's very selective picking out of some serials and not other (numerically adjacent) ones was pushing the bounds of plausibility on how they run their (evidently almost nonexistent) QA procedures.

Also, several years ago someone who I thought had very good contacts at Lyco said that not a single one of the "12 year limit" cranks had ever snapped.

As an amusing comment, one highly respected old US engine shop told me that Lyco used to buy, for decades, cranks from Krupp in Germany. They had zero defects for all that time. The trouble started when they started to make them in the USA. I wonder why they dropped Krupp? It may have been cost, or it may have been the massive corruption stuff for which Krupp/Thyssen, together with their old crooked chums Siemens got massive fines. Do a google on e.g.

krupp corruption

and you get reams of it. The Americans are very sensitive to this kind of thing and perhaps a top level decision was made to distance themselves from these German firms who were paying bribes to everybody who would accept them (Greece being one of many).

[BabyBear]

Thanks Peter, at the risk of demonstrating my lack of knowledge of such things can you give me a clue of how to go about it. Is it a case of searching the Lyco site?

BB

[peterh337]

I can't find it either... let me make enquiries.

[BabyBear]

Thanks, appreciated.

BB

[Prop swinger]

Off the EASA website: http://ad.easa.europa.eu/blob/20121901.pdf/AD_US-2012-19-01_1

[peterh337]

One US engine shop says:

After reviewing the AD, the only change to the AD is when the AD was to
take affect. No serial numbers have or will be added to the original
AD2006-20-09.

Mind you, going for an earlier start date is going to catch more engines... isn't it?

[BabyBear]

Thanks folks, I initially believed there had been additional shafts added, it seems not and the original tables remain the only tables. I will still check to ensure it has been addressed, or discounted accordingly.

BB