01rmb

And 50 hours ago the worse cylinder was 72/80... So good advice but worth caution because this engine was not going to do another 20 hours!

As discussed earlier in post After 300 hours - running mostly Avgas the pressure leak test was down in the 40's on 2 cylinders but worse it was picked up that there was leakage past the exhaust valves on at least one of the cylinders necessitating removing the heads for inspection. I have attached a photo showing the level of buildup from the lead fouling that was found before being cleaned up. The lead buildup had started to affect the exhaust valve sealing (small valve) and then the valve started to get burnt which you can see at the point closest to the spark plug. What you can't see is that on the underside of the valve there is a small hole being burnt through leading to low cylinder pressure and combustion into the exhaust. Eventually the leak will lead to the valve stem being burnt through and the valve head falling into the engine. Fall flat, the engine may at least run, fall at an angle and the piston impacts the valve head and leaves pieces of piston in the sump along with a pretzel of a piston connecting rod and more loose pieces of metal in the engine. But basically, if it happened when you were in the air, you will be landing rather quicker than intended. Following inspection of my engine the LAME advised that it would not have lasted the next 20 hours. The LAME removed all heads, gave them a thorough cleanup and replaced all valves and springs (cheap parts so not worth mucking around). Good as new and will easily last until the scheduled overhaul time. The consensus is that the problem is totally related to running avgas and the resulting lead fouling. Some running conditions (with longer idle times resulting in cooler combustion temperatures) will expedite the level of buildup and decrease the time to problems occurring. Two aircraft I know that are doing 20-25 hours per week each in typical ad initio training were having all sorts of problems with the engines including 2 near forced landings when running on avgas - After switching to premium mogas there have been no problems. Good enough evidence that following my own problem that I will only run premium mogas. Importantly - Do your preflight checks and at any sign of poor compression, leaking gas into the exhaust or rough running have a mechanic check the engine before the wheels leave the ground. If running avgas maybe it is worth inspecting the exhaust valves much earlier than scheduled maintenance advises if your running conditions may lead to greater lead fouling potential.

I am not a mechanic so take this for what it is worth which is a comment on my (as well as qualified and experienced others) view on how to possibly improve the engine situation in a positive and productive way. It is such a sensitive area for Jabiru owners and all the knockers but one that needs careful and proper analytical evidenced consideration. Is there something wrong with the way the Jabiru engines are being operated which is exasperating the premature failure of the engines? Engine cooling may be one area but another problem is possibly the fuel used. Having read about and personally seen a number of Jabiru engine problems both in flight and picked up during preflight/maintenance there is a view that lead fouling from Avgas is leading to deposits forming on spark plugs and valves. Due to the fine tolerances of the Jabiru engines one of the problems is that these build ups are causing exhaust valve leakage leading to the burning of the valve head and stem eventually resulting in the valve breaking free into the cylinder impacting with the piston leading to a full engine failure. This seems to be a particular problem occurring in the 300-700 hour range. This is one but by all means not the only answer to premature engine failure. Lead Fouling Lead (TEL - Tetra Ethyl Lead) is added to Avgas to act as an octane booster to prevent preignition in high compression engines - btw the level of lead is about 5 times what was in the old leaded auto fuels. The problem with leaded fuels is that they will leave lead oxide deposits in the engine if not fully burnt off. To assist, Ethylene Dibromide is added to the fuel to react with the lead oxide to become the more volatile Lead Bromide, a gas at 200-250 oC but it goes back to a solid as the exhaust gas cools. A high combustion temperature is required to ensure that this reaction works without leaving large amounts of buildup in the cylinder heads. Higher cylinder temperature also helps the rings to seal properly, limiting acid and lead by-products going into the sump oil leading to long term corrosion problems. (Jabiru moved to 25hr oil changes to prevent problems as a result of lead contamination of the sump oil.) If the engine is run at idle such as during warm up, taxiing and landing and the engine is shut down cool after a long taxi then there will be significant fouling especially around the spark plugs and exhaust valves. To make the problem worse, if the carburettor can not be set to run lean during idle then a higher fuel mix, then what is needed, will be fed into the combustion chamber making the temperature problem worse. Of particular note there was a large number of problems recently that affected all light aircraft resulting in major fouling of plugs resulting in replacement on the Cessna’s etc used for training at a major airfield due to what was thought to be a higher lead concentration in the Avgas used (but still in specification) so not just a Jabiru problem. Jabiru and other recreational sport engines are not high compression and don’t need the high octane fuels. The bing carburettor also can not be leaned. Jabiru engines support both Avgas and premium mogas but Jabiru recommend Avgas in preference identifying the knock resistance, availability at airports and the quality control whilst noting the lead fouling issue in the combustion chamber. Possible Solution (for some of the problems) Run unleaded fuel. At a location with high Jabiru hour usage, after a series of problems and following LAME advice, there have not been these problems experienced with the engines by switching to unleaded premium mogas fuels. If the heads are already fouled then switching to unleaded is not going to fix the damage already caused (and may even be making it worse due to the decrease in compression pressure resulting from leaky exhaust valves). Some engines seem to be fine running on Avgas and are getting long hours without problem but maybe due to them running at full power (hotter) for longer and less time idling they are not getting the buildup of lead around the valves. Preflight Inspection It has been recommended that whilst pulling the engine through before the first flight that in addition to feeling for poor compression and listening for mechanical noises you should also be listening at the exhaust for air escaping through the exhaust valves on compression. If you hear puffs of air escaping then further investigation of the exhaust valves is needed suspecting inadequate exhaust valve sealing and imminent problems. It was also suggested that the Jabiru engines normally run very well balanced and if they start to feel rough then it is worth investigating further. Full engine monitoring Full engine monitoring will pick up the exhaust valve leakage due to a rise in EGT identifying the need to pull the heads off to inspect. So maybe that is something we all should look at. One thing is certain though - if the problem is not identified and fixed then the engine will fail. I am experiencing this problem personally because my Jabiru is currently having the heads cleaned up and the exhaust valves replaced after 300 hours running mostly Avgas with a high level of idle taxi time and landings due to the nature of the aircraft usage and the airfield/s it is operated from. Luckily for me the problem was picked up during a 100 hr service so I did not have to worry about finding a nice spot to land… I do believe the engines are okay but that the recommended fuels for these engines should be investigated further and recommendations potentially modified. But for me, until there is easy access to unleaded Avgas, I am going to be only running on premium unleaded mogas to prevent lead fouling problems and eliminate contamination of the sump oil.

Below is the ADSB coverage map at 30,000 from Air Services. The red area is primary radar coverage and the purple is the ADSB coverage. I would assume the aircraft 'dropped off' the screen when it left the radar coverage area near Bourke. http://www.airservicesaustralia.com/projects/ads-b/

The way I read it, the cross country endorsement to the RPL will even allow you to fly greater than 25nm from the airfield. Additionally, the controlled airspace and controlled aerodrome endorsements are what is needed to allow access to controlled airspace and airfields. So a RA Aus pilot certificate with a cross country endorsement converted to the RPL with the controlled airspace and controlled aerodrome endorsements will be very liberating. Bring on Sept 1 (and an amenable GA flight instructor to do the flight review and grant the appropriate endorsements...). http://www.casa.gov.au/scripts/nc.dll?WCMS:STANDARD::pc=PC_101934 What limitations will apply to the holder of an RPL? Before using your RPL, you will need to: have a current flight review for the aircraft being flown (see CASA’s information sheet about flight reviews for more details) meet the medical requirements have conducted three take-offs and landings in the previous 90 days if you wish to carry passengers have a class 1 or 2 medical certificate to fly above 10,000ft, or have another pilot with you who has a class 1 or 2 medical certificate who is occupying a flight control seat in the aircraft and is authorised to pilot the aircraft. Unless you hold a navigation endorsement you are also limited to flying within 25 nautical miles of your departure aerodrome, your flight training area and the route between your departure aerodrome and the flight training area. You need to have a flight radio endorsement if you are going to use the aircraft radio during the flight. If you want to fly in controlled airspace, you must hold a controlled airspace endorsement. If you want to fly at a controlled aerodrome, you must hold a controlled aerodrome endorsement.

They appear to have dropped the requirement for 2 hours instrument time for the RPL. http://www.casa.gov.au/scripts/nc.dll?WCMS:STANDARD::pc=PC_101585 For a recreational pilot licence (RPL) you must be at least 16 years old. You must have a current medical certificate (this may be either Class 1 or 2, or a recreational aviation medical). However, there are conditions on the number of passengers you can carry if you hold a recreational aviation medical certificate only. Applicants must: have 25 hours’ flight time (comprising 20 hours dual and five hours solo), pass an aeronautical exam with the associated rating, pass a flight test. RPL holders are limited to: 25nm from the aerodrome where the flight began, the designated training area, or a direct route between the two, day VFR private operations in a single engine aircraft. If an individual already holds a pilot certificate issued by a recreational aviation administration organisation or a GFPT, they will be able to exercise the privileges of a RPL after they have conducted a flight review. This is also reflected on the proposed new forms http://www.casa.gov.au/wcmswr/_assets/main/lib100191/3form61-1ra.pdf http://www.casa.gov.au/wcmswr/_assets/main/lib100191/fc-61-1re.pdf

I couldn't agree more. The whole detail in the report and the focus on the administrative details around the training and aircraft registration is irrelevant to the actual problem which was that a large temporary obstruction was constructed at the end of the runway without proper advice to airfield users. With the ferris wheel there the strip probably rightly should have been closed. A 3knot tail wind and 2kg over weight - so marginal a difference. If it was not this pilot in this aircraft it could have been anybody else who happened to be a little long on a short runway having to go around and happened to slightly drift off centre line - very human and should be expected within normal human tolerance. Aircraft Risk Management - keep them out of the air and they will never crash...

I have said this elsewhere, but, it is ludicrous that I can learn to fly in controlled airspace at a class D airport under an exemption provided to the flight school but once certified I can't continue to do so under my own qualifications. Are we sure CASA does not mean 'stupid bureaucracy' !! Surely allowing a controlled airspace endorsement to RAA pilots with the relevant aircraft, training and equivalent medical conditions as a RPL pilot makes sense. Let alone the stupidity of me having an aircraft with numbers on the tail restricted to 600kg whilst the same aircraft looked after by the same people with letters on the tail is allowed an extra 100kg. If you live in the country and don't go anywhere near controlled airspace then don't do the endorsement or get the medical but for those that live 10 minutes from a controlled airfield with controlled airspace to the north, east, south and west it would be real handy to be able to have access to these areas as any other 'recreational' GA pilot does. If the RPL and RAA pilot certificate are meant to be equivalent then make them equivalent and don't force RAA pilots to have to do a RPL/PPL just to get access to controlled airspace. Same pilot, same training, same aircraft, same maintenance, same medical but different rules - no sense... If you don't want the extra entitlements then don't do them up but for those that do then why can't the rules be applied the same across the whole airspace.

I use Vuplex and find it very good. Gets rid of any bugs and grime very well and leaves the screen nice and clear. Not cheap though. Some people use Mr Sheen as an alternative. http://vuplex.co/ http://www.bcf.com.au/online-store/products/Vuplex-Plastic-Cleaner-Polish.aspx?pid=155758#Cross

So how is this going to be fixed? Is the RAAus board or operational manager lobbying CASA to address this situation? There surely is enough evidence to argue that the existing CTA restrictions are jeopardising safety rather than making it safer. I flew past Ballina on the weekend - Jetstar on the runway ready to take off and using proper radio practices I advised location and allowed him to take off safely and exit the area before I passed through - surely transiting a CTA with a traffic controller would be safer. I can land and transit Ballina with jet traffic but a few miles down the coast at Coffs I have to go the low way around. Trying to make sense of it makes your head explode. Why should pilots with the necessary training be restricted because they are certified through RAAus but instead have to do a PPL or RPL through a GA school? What is the difference in knowledge/competency that should restrict one over the other from transiting or using a controlled airfield or airspace? I would even accept the BS (with some scepticism and annoyance) that you would need a class 2 medical or doctor medical to ensure safety.

Flew in to Sth Grafton on sunday and met Col from the aero club. Nice guy - He showed us around the club house and made us feel very welcome. We'll make it to a fly in there for sure as well as head down there some more.

Don I know you have said 'at least' but is the issue of using CTA Airfields with appropriate training for CTA being considered by CASA? I am not looking to land at a major airport like Brisbane, Mascot or Tullamarine (nor would most GA pilots anyway) but Archerfield, Jandakot, Parafield, Moorabbin, Camden and Bankstown plus ones like Coolangatta, Sunshine Coast, Coffs Harbour, Mackay, Rockhampton and Townsville would be extremely useful for many of the RAA pilots living near these areas or flying through and wish to stop there as a stopover or for fuel. I am still at a loss as to why I can train and fly solo out of Archerfield but once certified am now restricted from the same airfield. I would even accept the need for a Class 2 or the DL medical.

I learnt to fly and gained a RAA pilot certificate with a cross country endorsement in class D airspace at a class D airfield which required me to get a class 2 medical, I also have a 24 registered aircraft that has a transponder (not required for class D btw) that is maintained by a LAME because it is used for hire then what more is needed? Having finished my training I am now restricted from controlled airspace and controlled airfields - the same airspace where I trained because RAA does not have a CTA endorsement. If CASA will offer an almost direct swap for my pilot certificate but include CTA access whilst RAA is restricted from having a controlled airspace and airfield then I am up for that. I think there is a good argument by RAA to get the same CTA privileges but who knows if this will ever actually happen. Does anyone know if this is on the agenda? The bonus of the RPL is that I can also use it to fly an aircraft up to 1500kg with more than one passenger which would allow a Cessna 182 with all seats filled. I could do a PPL but if I am not interested (at this stage) of doing multi engine or night flying then why bother if the RPL ends up being easy enough. Ease all depends on how much of a run around the GA schools give people. There is a high level of elitism from the GA schools on converting to a PPL when it should not be that big a deal especially if you have spent the same amount of time in the circuit as any of the GA students. If someone who has only ever flown in open country with few aircraft around, has issues with traffic control or has suspect health issues then it is a good thing that they are kept away from controlled airspace until they have done the necessary extra training and are deemed safe and competent.

“A pilot certificate is equivalent to an RPL” but the RPL allows controlled aerodrome and controlled airspace endorsements and ability to carry more than one passenger whilst RAA pilot certificates are banished to the country with only one other person. You can get so much more from the RPL for no more trouble and can even fly the same aircraft but with a VH registration. Is RAA going to be allowed to have the same privileges or is this just a way for CASA to marginalise their competition and limit them to only looking after low performance aircraft? Looks like I will be lining up to get a RPL as soon as they come out. It will be about time when I need to do my BFR so I will need to do a flight review anyway!!

Here is the modification from Jabiru for changing the voltage output of the alternator by doubling the stator winding length. http://www.jabiru.net.au/Manuals/Engine/AVDALSR087-1_12_Pole_Alternator_Mod.pdf

Andy - I absolutely agree - I am not condoning poor QA. If a product is not being produced as designed and failing because of that then there is a problem that must be addressed. It must be made fit for purpose and that includes maintenance in accordance with procedures and the normal behaviour of pilots to ensure the product performs as expected. Failure at low hours is not acceptable and should be made good by the manufacturer as a warranty claim. If I had a similar problem with my aircraft I would also be joining the line of disenfranchised owners. What I am talking about is I would like be able to utilise an improved design or modification that has been endorsed by the manufacturer without losing my registration by having to go through a long winded and costly certification process. In essence, to allow 24 registered aircraft to take advantage of improvements such as those suggested from CamIT (and I am sure even Jabiru themselves) without loss of aircraft 24 registration which otherwise won't be made available because to certify the changes would cost more than what the business can afford. And with the state of aviation such as it is, few businesses can afford it because of the small volumes and low returns. I could do it with a 19 registration aircraft but why should I not be allowed to do it with a 24 registration aircraft and then not be able to use it for training or hire. All recreation aircraft are produced to a weight and cost model to meet market demands. I would pay more for better quality but not for the unnecessary cost just for paperwork. I look at the possible improvements already in the market and wish I could do something about it but can't because I will lose the registration. If reliability improvements can be introduced with minimal cost then everyone wins. I believe we would see more improvements being introduced if this was the case. As Ozzie said - it would be good to see RAAus lobbying CASA to allow these improvements to be introduced for the good of the recreational market. Quality is still with the manufacturer to maintain...

Isn't that the key to solving the problem? Actually working with Jabiru to solve the reliability issues achieve a whole better outcome than knocking what is arguably the biggest gain in recreation aviation in Australia. If we take away the hurdles and no doubt excessive costs to certifying engines or modifications Jabiru, CamIt and whoever else has done a reasonable level of testing could introduce reliability gains for consumers easier and cheaper. I am sure jabiru would like to do more to improve their product where possible but are hobbled by bureaucracy and the resultant costs. If you have gone through the costs to certify your product but every change costs a fortune to do it again I am sure that you would be hesitant to do anything unless it was absolutely necessary. Maybe the RAAus board members could help the industry grow rather than try to bring it down by working with CASA and the industry to achieve a win win situation for everyone. I know I would like to have the most reliable aircraft possible without the excessive costs.