New through bolt AD

[Oscar]

So let's see if we can re-cap here quickly:

 

1) Jabiru issued a SB and honoured its obligations to rectify the problem for a period of 12 months, but is now reinforcing the earlier requirement for those people who had not undertaken the work during that period (a not unreasonable situation to prevent 'liability' in perpetuity for those owners who had not availed themselves of the information AND taken the opportunity to have the work done at Jabiru's cost);

 

2) As Andy's experience shows, a conscientious and intelligent operator who closely monitors the engine performance and applies sensible operating procedures as far as possible, can indeed get a life from the engine that very significantly exceeds the expectations of some!

 

It seems to me, that Jabiru made a pretty damn reasonable response to a problem that emerged. It may not have been 'perfection', but it was consistent with a company ethos of supporting its customers. I know for a fact that Rod Stiff used to fly out to crashed Jabs. and do repairs in the field to get owner's aircraft back in the air.

 

Please remember, those who enjoy 'Jab. bashing', that Jabiru arose from nothing to become the most successful aircraft production company in Australia's history. In terms of the spread of international sales, Jabiru is one of the best-performing companies we have ever produced! Look at what you get in a factory Jab. 230 or 430 for the money vs. a Cessna 162 - let alone a 172, for over twice the price, against which a 430 is more than competitive.

 

Rather than just blindly derogate Jabiru for its faults - how about looking at value-for-money? Initial cost, running cost per hour, capability delivered, and injury/accident rate. Show me a better product.

 

 

[turboplanner]

Because there are statutory requirements which no one is exempt from, so there's no point in trying to sell the "little guy" emotion.

 

However, as Frank Marriott has tried to get across several times, it might just pay to check the facts before getting emotional.

 

 

[facthunter]

If a manufacturer has to be responsible for fixing things for nothing in perpetuity and bypass a "free to rectify" period and irresponsibly continue to operate the engine, you have LOST me. All warrantee work I have seen done on Jabs was done in such a way that I felt the maker was trying to do the right thing by the product and the purchaser. AS far as I'm concerned anyone who doesn't do all the advisory? mods is a R Cranium, and shouldn't be let off his lead. Nev

 

 

[Oscar]

Because there are statutory requirements which no one is exempt from, so there's no point in trying to sell the "little guy" emotion.However, as Frank Marriott has tried to get across several times, it might just pay to check the facts before getting emotional.

OK, so tell me what action Technam has taken re the known problems with the P92 u/c (by way of looking at 'industry-standard' fault rectification performance). Did they pick up the cost of

 

RA-Aus AN150911-1 if cracks were found? Several P92s have had the u/c fail simply on landing, without significant abuse; there is a design fault there. I don't know what Technam's response was, but if we're going to put Jabiru under the spotlight, then let's at least establish benchmark performance standards.

 

 

[facthunter]

I don't know what the later ones are like, but the crashed early one I inspected was not put together too well. I wouldn't

 

be satisfied with the quality. Partinavia build them don't they? Nev

 

 

[dazza 38]

I don't know what a Technam is , but I have flown various Tecnam's and the airfield is a bit rough at Boonah. But I haven't seen any U/c problems.

 

 

[fly_tornado]

is it a case of an RAA plane not reporting a heavy landing and the said aircraft "suddenly" developing issues?

 

 

[facthunter]

That could well be. There would be reluctance to report a "heavy" landing , groundloop etc,by most people. I don't think that is responsible at all. Similarly any flap overspeed or strong turbulence should warrant an inspection. We might have to accept a more responsible attitude to be more safe. Consider the person who flies it next. Nev

 

 

[Oscar]

is it a case of an RAA plane not reporting a heavy landing and the said aircraft "suddenly" developing issues?

Read: http://aviation-safety.net/wikibase/wiki.php?id=48413

 

However - that is not the issue I raised. The issue is: a determined fault > manufacturer issues a SB > does manufacturer automatically pick up the costs of complying with the SB?

 

It appears that Jabiru made a fair and honest attempt to rectify the problem, at (at the very least) minimal cost to the owner. Is that 'industry-standard' performance?

 

 

[facthunter]

Cause "Undertermined. Presume they mean undetermined? Nev

 

 

[Dafydd Llewellyn]

I don't know what a Technam is , but I have flown various Tecnam's and the airfield is a bit rough at Boonah. But I haven't seen any U/c problems.

I have. And none of you have answered Oscar's question, which was whether or not Tecnam paid the cost associated with AN RA-Aus AN150911-1.

 

 

I would also point out that since CASA has not seen fit to issue an AD in regard to the Jabiru through-bolts, it follows that CASA does not consider them a threat to safety.

 

 

[frank marriott]

I don't know what the later ones are like, but the crashed early one I inspected was not put together too well. I wouldn'tbe satisfied with the quality. Partinavia build them don't they? Nev

Nev

 

On a Partinavia I used to operate we had a undercarriage leg break off on landing but it did hit an antnest which was in about 2 feet of grass so not visible to the pilot but on inspection after the event the bolts which broke were half broken for some time obvious by the surface rust on half the surface of the broken botlts.

 

An AD came out later about inspection of the undercarriage bolts at certain intervals [i can't remember the details exactly]

 

In defence of the aircraft/manufacturer I must add

 

[a] It was used in training for twin endorsements, and

 

They (or at least the few I flew) had a max landing weight which required a flight of about 150nm if you took off at MTOW to get down to MLW. We did operate a lot of charter with 6 POB to an island only 30nm away. Although there was no evidence to support the the suggestion, it is a reasonable guess that pilots would accept whatever fuel was on board and not worry about defueling for a half hour charter flight in the middle of other duties.

 

[c] I don't think the manufacturer intended the design to include hitting an eighteen inch antnest.

 

The point being that some word of mouth complaints about different aircraft may be different to what appears when all the circumstances are known.

 

Of course I was not guilty of any of the above behaviour!!!!!!!!!

 

 

[facthunter]

An overweight landing would require an entry in the AMD18, (or whatever it is called now). Nev

 

 

[Guest Maj Millard]

Frank, The P68 Partenavias commonly took the heads off the two outer MLG saddle bolts, especially if they were flight training or operating heavy. It wasn't unusual to find at least one of the four bolts broken during a 100 hrly inspection. You could tap on the fibreglass fairing below the saddles and listen for the rattle of a broken bolt head, as that's where they ended up in most cases.

 

A good maintenance org would just replace them with new bolts as part of a normal service. It was a weakness and they probably needed to be the next size up. The MLG chromeoly truss frame that held the saddles needed to be also checked for cracks.

 

The Tecnam aircraft have a similar set up I believe, in as much as they have separate legs for each side as opposed to one single one piece leg....Additionally there are few aircraft in service that don 't have some 'weak link', some more serious than others, and some easier to maintain than others. It just comes with the territory................Maj...

 

 

[Oscar]

Cause "Undertermined. Presume they mean undetermined? Nev

The P92 undercarriage bolts are subjected to a leverage-induced stress due to the design of the u/c leg attachment that imposes tension on the bolts for which they are inadequate to sustain (same problem manifested itself for Citabrias, incidentally.) It does not take an especially heavy landing to fracture the bolts, following which the affected leg will depart the aircraft and the resulting cost of that makes complying with the Jab. SB on the through-bolts look like a bargain.

 

Unlike the Aeroprakt response to the cracking of the wing carry-through member structure ('it's designed to flex'), Tecnam have adopted a responsible response to an engineering analysis of the problem - good on them for that. My question remains: has Tecnam (with due recognition of my original error in its name) provided to its clients the same level of cost-free (or at least, minimal) response to the problem as Jabiru did with the through-bolts issue?. How well does Jabiru's response stack up against the response of other manufacturers faced with similar types of problems with their aircraft?

 

Some respondents on this thread have suggested that Jabiru must price in to its sale cost, on-going maintenance of any issue that may emerge. OK, that is one side of the story. Let's look at another example of a company - Textron - that has without a doubt taken that matter into consideration with respect to its product for this class of aircraft.

 

Compare a J120 - on offer, right now, for $58K including GST from the factory. A 162 is $170k.

 

I've compared the performance etc. figures, and a 162 does not offer around 2.9 times the performance by any objective measure in any area. I don't have any data to compare Cessna's propensity to respond to rectifying issues that have/may arise for an owner of a 162. We DO know that Cessna have had serious problems with the spin-recovery of the 162, with a least one early aircraft entering an unrecoverable spin and several different tail designs being pursued to get the damn thing acceptably safe.

 

One respondent on this thread has chided me for using 'the small guy' argument as a defence of Jabiru. Is that fair? Of the 'large guys', only Cessna has ventured seriously into the LSA market: Piper has withdrawn, Beechcraft never tried. Have I missed any 'large guy' manufacturer that is a player in the LSA-class market, and who, therefore, has the depth of pocket to provide endless no-cost support of their product?

 

If I am pushing a 'small-guy' emotive argument: give examples of a better response from any manufacturer of this class of aircraft. Show me the 'gold standard' that Jabiru have failed to meet.

 

 

[Guest Maj Millard]

Oscar, that's not hard to answer at all, in fact its quite simple, the Rotax 912 is the 'gold' standard that jab has to match....... Maj....

 

 

[facthunter]

I had a Citabria. There is a lot of leverage on the bolts and mine were not a problem but used in training I am sure they could be. A fibreglass plane like a 230 compared with the 162 Cessna would always be a lot cheaper to produce. They are cheaper to repair too. You are not actually comparing apples with apples ,though but the Jabiru is a value plane and you can easily fly one across Australia, so they play a role for sure. Nev

 

 

[Dafydd Llewellyn]

I had a Citabria. There is a lot of leverage on the bolts and mine were not a problem but used in training I am sure they could be. A fibreglass plane like a 230 compared with the 162 Cessna would always be a lot cheaper to produce. They are cheaper to repair too. You are not actually comparing apples with apples ,though but the Jabiru is a value plane and you can easily fly one across Australia, so they play a role for sure. Nev

Can you tell me whether your Citabria had the original U bolt undercarriage attachment (which broke) or the CAR 35 approved replacement using a saddle plate and two ordinary bolts?

 

 

[facthunter]

I don't know Dafydd. It was totally rebuilt in 1993 and I was told of the problem and kept an eye on it for movement. My plane had a wooden spar 7ECA so I couldn't lift or jack it easily. I was the only person who flew it ever ( when I had it)The guy who built it did all the annuals. He is a a bloke who tackles any thing fabric wood sheet wing, fuselage reskinning engine shop Got jigs for most work. The Cessna wing skins look better than from the factory. STOL kits etc.

 

The plane unfortunately got written off after I sold it. but the same guy bought the wreck and is rebuilding it. It will be as good as new I am sure. nev.

 

 

[Oscar]

Oscar, that's not hard to answer at all, in fact its quite simple, the Rotax 912 is the 'gold' standard that jab has to match....... Maj....

Well, a damn good point of reference! Rotax provides NO warranty as to the selection, use etc. of the 912. It is at the owner's risk as to the use it is put. So when the crankshaft comes into issue for multiple thousands of them, you're on your own.

 

 

[Oscar]

I had a Citabria. There is a lot of leverage on the bolts and mine were not a problem but used in training I am sure they could be. A fibreglass plane like a 230 compared with the 162 Cessna would always be a lot cheaper to produce. They are cheaper to repair too. You are not actually comparing apples with apples ,though but the Jabiru is a value plane and you can easily fly one across Australia, so they play a role for sure. Nev

Nev: so, if one is not comparing 'apples with apples' - what the hell do you get extra in the 162 for more than 50% of the cost of a 230? MTOW- no. Load capacity? - no. Space? - no. Economy? - no. Cost/hour? - no. PtP time - no. Seriously - give me a reason that makes ANY sense for paying the money for a 162 over a 230.

 

 

[Dafydd Llewellyn]

I don't know Dafydd. It was totally rebuilt in 1993 and I was told of the problem and kept an eye on it for movement. My plane had a wooden spar 7ECA so I couldn't lift or jack it easily. I was the only person who flew it ever ( when I had it)The guy who built it did all the annuals. He is a a bloke who tackles any thing fabric wood sheet wing, fuselage reskinning engine shop Got jigs for most work. The Cessna wing skins look better than from the factory. STOL kits etc.The plane unfortunately got written off after I sold it. but the same guy bought the wreck and is rebuilding it. It will be as good as new I am sure. nev.

Well, if you didn't have main U/C U-bolt problems, it almost certainly had the CAR 35 mod. that I designed in the late 1970s. The original factory installation used a U-bolt, which pulled closely down onto the underside of the leg. In glider towing usage, these failed within a couple of hundred hours. The reason was that as the leg deflected on touchdown, it pivoted about the corner of the (square) lower longeron, and exerted a "prying" effect on the bolt. The head-breakage on Partenavia undercarriage legs would be from a similar cause. The cure was rather subtle; when the leg is bent during manufacture, it take on a curvature across its width ("anticlastic curvature" - which has the result that it rests on the lower longeron at its edges, and is very slightly convex on its underside. If one replaces the U-bolt with a sufficiently rigid saddle piece, there will be air between the ends of the saddle and the underside of the main leg, at the edges of the leg. When the leg bends under the landing impact, the transverse curvature reduces a bit - and this can provide sufficient movement to compensate for the prying effect. It takes careful design to balance the two effects, but if you get it right, bingo - no more bolt problems.

The Tecnam leg attachment had a similar problem. This sort of thing is not likely to be picked-up in the initial design & certification of the aircraft; it's the sort of thing that shows up in service. The CAR 35 system existed to fix those sorts of problems. There's hardly an aircraft on the Australian civil register that does not have some sort of CAR 35 fix for some chronic issue. This is simply the reality of the game; aircraft production numbers are never sufficient for these sorts of subtle things to be caught before the aircraft get out into the field. I wrote over 3000 Engineering Orders for issues of this nature, between 1975 and 2011 (including several for Tecnams, under No Technical Objection notes from the manufacturers). This is the real world; it's unrealistic to expect anything else.

 

 

[DrZoos]

Did anyone pay a LAME to do the through bolt replacement. If so what did it cost please.

 

 

[Guest Crezzi]

Well, a damn good point of reference! Rotax provides NO warranty as to the selection, use etc. of the 912. It is at the owner's risk as to the use it is put. So when the crankshaft comes into issue for multiple thousands of them, you're on your own.

Not quite accurate - the standard Rotax 912 warranty is 18 months or 200 hours and I've had replacement parts FOC (when required by SB) for engines 2 or 3 times past those limits.

Cheers

 

John

 

 

[facthunter]

That is not an unreasonable thing to do. It's marketed as a superior product and has the name Rotax to protect. Nev