gandalph Posted November 30, 2014 Posted November 30, 2014 Yes but what about when one breaks or pops the valve head off, which has happened several times when the inadequet upper retainers fail. That still leads to a catastrophic engine failure ...piston relief or not. Also convieniently forgotten are all the failures of the flywheel bolts which often leads to sudden engine stoppage due ignition failure. This critical area has not been adequetly addresses yet. Data? I presume that as a board member you would have access to the details of those types of failures. Will you please provide some details e.g. numbers that might give us some confidence in our post? 1 1
turboplanner Posted November 30, 2014 Posted November 30, 2014 WHAT? He's not allowed to join the discussion? Is what he said not correct? 1
gandalph Posted November 30, 2014 Posted November 30, 2014 WHAT? He's not allowed to join the discussion? Is what he said not correct? TurboP. If you are asking that question of me regarding Ross' latest post, then yes, of course he is allowed to join the discussion. What in my response to him would cause you to think otherwise? Is what he said correct? Well that was the thrust of my request to him for some verified facts. Again I don't quite understand where you are coming from.
Guest Maj Millard Posted November 30, 2014 Posted November 30, 2014 WHAT? He's not allowed to join the discussion? Is what he said not correct? Some people can't handle the truth turbo....hence the 'head in the sand' syndrome which has added significantly to the overall problem.
Keenaviator Posted November 30, 2014 Posted November 30, 2014 How many flywheel bolt failures have there been since the upgrades were introduced? Are these failures happening to both solid lifter and hydraulic lifter engines? I wouldn't be surprised if these failures are directly related to detonation too. The failures in valve retaining components should not be hard to rectify.
vk3awa Posted November 30, 2014 Posted November 30, 2014 All of the issues you have mentioned are correct over the history of the 2200/3300 series of engines. However, some of the problems you have raised may no longer an issue as they have been rectified over time or the affected engines are no longer in service. You quote "larger" valve relief.........not larger but either valve relief machined into the piston crown or not. I have been involved with the Jabiru product since before the intoduction of the 2200/3300 series engine having my first flights in a 1600 powered version. I am an L2 and have ben trained by the Jabiru factory and Wayne Johns in SA on Jabiru engine rebuilds so I have some experience. The current prevalent issues are through bolt failure/crankcase fretting and valves sticking in guides. The piston valve relief might be a "bandaid" fix but I can tell you that I'm a lot happier flying with one of these engines knowing a stuck valve will not cause a catostrophic engine failure. I also read a few posts citing engine overheating problems. This has not been an issue since the introduction of the fine fin series of heads some years back. So, during the evolution of the engine the issues have changed. My feeling is CASA will be targeting the current series of production engines and not ones made ten years ago with some of the problems you have raised in your post. Just reread my post.....apologies for the typos......but you get the message.
Downunder Posted November 30, 2014 Posted November 30, 2014 The solution to sticking valves is to flycut the pistons? THATS NUTS! Treating the symptoms, not the cause....... 4 1
gandalph Posted November 30, 2014 Posted November 30, 2014 Some people go through life with their head in the sand, others with theirs in a much darker place. 2 1
Guest Maj Millard Posted November 30, 2014 Posted November 30, 2014 How many flywheel bolt failures have there been since the upgrades were introduced? Are these failures happening to both solid lifter and hydraulic lifter engines? I wouldn't be surprised if these failures are directly related to detonation too. The failures in valve retaining components should not be hard to rectify. That's correct ...then why don't they rectify them ??.........
frank marriott Posted November 30, 2014 Posted November 30, 2014 That's correct ...then why don't they rectify them ??......... Madge at her best! 3
Teckair Posted November 30, 2014 Posted November 30, 2014 people who expect a GA style experience and reliability. And there lies the problem. News flash the AUF was not supposed to reinvent the GA wheel you guys should have GA licences. 3
vk3awa Posted November 30, 2014 Posted November 30, 2014 Yes but what about when one breaks or pops the valve head off, which has happened several times when the inadequet upper retainers fail. That still leads to a catastrophic engine failure ...piston relief or not. Also convieniently forgotten are all the failures of the flywheel bolts which often leads to sudden engine stoppage due ignition failure. This critical area has not been adequetly addresses yet. Maj, I take offense at your suggestion that I am conveniently forgetting all the other failures. Without getting into lengthy discussion I said "current prevalent issues". I did not conveniently discount the other issues as you suggest. From my experience the most "prevalent" problems of recent times have been through bolt failures and valves sticking in the guides. I maybe should have also qualified my comments by saying in standard Jabiru configuration. (airframe/engine/propeller). There are probably thirty or so Jabiru powered aircraft in my area and I'm pretty well attuned to what engine problems have been encountered over the last ten years. I have yet to see one caused by the valve retainer failing, although I know it has happened. I have seen one failure due to flywheel bolt failure when a non-standard prop was fitted. I have tried to provide a non-biased, factual input based on my experience with Jabiru engines. In light of your comment which raised the question my integrity and raised my blood pressure a tad, I have made my final post. In closing, my post was in no way supporting the integrity of Jabiru engines or the factory customer service. 3 1
gandalph Posted November 30, 2014 Posted November 30, 2014 That's correct ...then why don't they rectify them ??......... Kenaviator asked (post 1485): " How many flywheel bolt failures have there been since the upgrades were introduced? Are these failures happening to both solid lifter and hydraulic lifter engines?" Again Ross, Are you able to provide an answer from the RAA files? I assume that as you raised these failures in post #1480 today you must have some facts that you could share? 3
Teckair Posted November 30, 2014 Posted November 30, 2014 Dutch r, I haven't operated to "private" rules in M/E. I have always operated to "theoretically" being able to fly on one, weights. Earlier aircraft like DH Dragonfly and Miles Gemini were never required.If you fly a twin (or more) at a weight that won't fly engine out, you have an aircraft that has twice the chance of having a motor bring you to grief, plus the possibility of control problems thrown in if you don't understand assymetrical thrust and Vmc (a)& (g). Nev I am no expert on this but I thought most piston engine twins were not good on one engine and struggle just to maintain height, I can think of two crashes where everyone died where the pilot tried to make it home on one engine.
gandalph Posted November 30, 2014 Posted November 30, 2014 Hey VK3WA, Don't let the Maj get to you. He has strong views on this subject and he can sometimes get people stirred up with his assertions. He is a member of the RAA Board and as such I expect that he has better access to details of failures reported to RAA than you or I. The problem we often have here with his posts is that he refuses to back up his assertions with anything other than heresay. You on the other hand would seem to have factual "coal face" information and your input is therefore quite valuable. I urge you not to run away & hide but stay on and help increase the store of verifyable facts in this site. There are many good contributors and if you stay on you will easily identify them. 1 4
facthunter Posted November 30, 2014 Posted November 30, 2014 You will have to fly with the other engine on a high power setting and it may give up if it's not in good nick. What's the point of having two engines if it won't fly one engine out? You have a decision point (called as a speed ) on every take-off calculated for density height runway length and slope and on the CRITICAL engine failing, before that point you stop and after it you GO. We are running two discussions here. The subject should be adhered to We are off topic..Nev
gandalph Posted November 30, 2014 Posted November 30, 2014 I am no expert on this but I thought most piston engine twins were not good on one engine and struggle just to maintain height, I can think of two crashes where everyone died where the pilot tried to make it home on one engine. The old saying was that the second engine enabled you to fly to the site of the crash.
alf jessup Posted November 30, 2014 Posted November 30, 2014 Alf. ALL modern twins not only stay in the air with one engine out, they make the minimum climb gradient in the segment after takeoff. Plus a few other like go round on one engine This is assuming you fly the plane to the parameters required, which can be pretty critical. Nev And you assume the modern twin is giving 100% power as per quoted performance figures, and the airframe is like it was when it came out the shop, and your not overloaded, and yes you the main reason for it crashing fly's it as perfectly possible to the book quoted figures. Lot of variables there Nev. Me I would rather the single up front any day to a twin on take off, well an old piston twin that is when the engine fails, only got one thing to concentrate on then. Alf 1
gandalph Posted December 1, 2014 Posted December 1, 2014 "Many" of the broken thru-bolts were on engines that had not been upgraded. Deb, do you have the facts to back that up? Or is it just a guess/wish? I'm trying to persuade Ross to back up his assertions with data so it doesn't help much if the rest of us start making unsupported statements. 1 2
motzartmerv Posted December 1, 2014 Posted December 1, 2014 If you discounted the number of thru-bolt failures due to non-compliance, this whole situation would have been unlikely to have occurred. What absolute garbage. 1
Keenaviator Posted December 1, 2014 Posted December 1, 2014 Maj, I take offense at your suggestion that I am conveniently forgetting all the other failures. Without getting into lengthy discussion I said "current prevalent issues". I did not conveniently discount the other issues as you suggest. From my experience the most "prevalent" problems of recent times have been through bolt failures and valves sticking in the guides. I maybe should have also qualified my comments by saying in standard Jabiru configuration. (airframe/engine/propeller). There are probably thirty or so Jabiru powered aircraft in my area and I'm pretty well attuned to what engine problems have been encountered over the last ten years. I have yet to see one caused by the valve retainer failing, although I know it has happened. I have seen one failure due to flywheel bolt failure when a non-standard prop was fitted. I have tried to provide a non-biased, factual input based on my experience with Jabiru engines.In light of your comment which raised the question my integrity and raised my blood pressure a tad, I have made my final post. In closing, my post was in no way supporting the integrity of Jabiru engines or the factory customer service. Mate, your posts are spot on. It's very unfortunate that there are some people on this forum who have poor personal communication skills and fly off the handle regularly with highly emotive responses, generalisations and offensive remarks. In fact, at the moment I feel like making a comment about the relationship between peanuts and monkeys but that may not be appropriate.
motzartmerv Posted December 1, 2014 Posted December 1, 2014 Garbage? Weren't you flying around an aircraft Merv that hadn't been updated by the due date? You don't think others are doing the same?Apologies, my information may have hit the public too soon. Wait till you hear more from CASA, Jabiru and RAA then refer back to my post later. Nostradamus is my mentor. Yes, thats true. One of the through bolt failures was post an upgrade that wasnt done. But the other 3 have been on latest spec bolts, and 2 of them were installed by the factory.. Your contention sounds like just more Jab blaming everyone else rubbush that has landed them in this pickle..Good luck nostredamus (by the way not one single prediction he made has ever been proven to come true BEFORE it happend) You dont need a crystal ball to see the unacceptable failure rate of Perfectly maintained engines. Do you happen to work for Jab ? 2
pmccarthy Posted December 1, 2014 Posted December 1, 2014 And there lies the problem. News flash the AUF was not supposed to reinvent the GA wheel you guys should have GA licences. News flash - I do have a GA licence, have had it for 43 years, but also have been a member of AUF/RAA since 1992. I would encourage members to be accepting and inclusive of all RAA flyers at both ends of the spectrum, we should support each other. But I find whenever modern composite aircraft are mentioned, there is always someone who would like to see them out of RAA. I really dont understand it. Edit - I should have said higher perfomance aircraft, there are lots of good aly ones about! 1 3
gandalph Posted December 1, 2014 Posted December 1, 2014 Well that was quick work eh Merv? The Mods have their eyes peeled today it seems.
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