Vev

Well done FG ... like so many things in life, practice and determination to win will get you there ... you are well on the way.

Cheers

Vev

One of the key points in the article was its affordability over other amphibious aircraft, but they failed to say what it was???… this feels disingenuous to me and spoilt my first impressions. I hope their new marketing manager repositions their offer to meet our intelligence in their future marketing campaigns.

Cheers

Jack

Fuels

I dont think AVGAS wont dissapear for some time, it will just get dearer until at some point we stop buying it

My bet is that we will see "AVPULP" turn up, clean QA assured PULP which will replace it, and these extra features will mean higher price!!! So back where we are now but paying similar price for lower octane unleaded fuel which looses performance after a few weeks in the tank.

I don’t think we are at risk of Avgas being pulled for some time. There was a plan presented 3 weeks ago to the US EPA by the Industry Avgas Coalition to develop a programme called “FAST” (Future Avgas Strategy & Transitional Plan) to develop a viable “drop-in” fuel solution.

In terms of the near future … It’s reasonably clear we will see a lead reduction (may be 50%) on the current LL100 to move towards meeting the 2006 Friends of the Earth Petition to outlaw lead. It’s also clear that aviation engine designs will increasingly accept high octane zero lead fuel formulation to also reduce the lead demand.

In my view, there is still a heap of data needed to understand the impact of lead on society from avgas (notwithstanding the fact that lead is harmful) and a bunch of petrochemistry research to develop a suitable “drop-in” fuel product that will provide safety with engine durability at an affordable price.

Avgas will be around for a while yet!

Cheers

Jack

Diesel Waxing

How do the new diesels go for vibration and how does the fuel go at low temps without waxing and not flowing at or below zero degrees?Brian

Excellent question re Diesel Fuel Waxing …

In my view, Diesel Fuel will never be suitable for aviation use in its current formulation because of the risk of waxing.

Diesel fuel "Cloud Point" varies around Aust from state to state throughout the year … what works in one geography will not be suitable in another.

If you were to fill your tanks and fly south …. leave fuel in your tank from a warmer month and then use in a cold month … fly at an attitude that chills down the fuel in your tanks … you could end up with wax forming in the fuel lines or blocking filters.

As an example, over a 30 day period between say Gladstone and Brisbane there is as much as a 12deg C difference in Cloud Point by government regulation. If you were to fill in Gladstone and fly South to Bris 30 day later you could easily find you are operating beyond the safety parameters of the fuels temperature design limits.

On the other hand, Jet A1 makes a very good alternative to Diesel fuel as it is designed to operate over an extreme range of temperature and will happily run in a diesel engine application, that is, so long as the engine has been designed to use it.

Cheers

Jack

Hi 80knts,

Seriously.. do you mean that? I'm no expert in metallurgy but I would think the current 4140 chrome moly single billet cylinder is miles ahead of an aluminum/stainless combo any day.... wouldn't your suggestion just add weight, complexity and cost on a cyl that works fine?

Cheers

Jack

Please explain?

Originally had the larger KFM engine. Then they were discontinued and Jab decided to make their own version. I'll make one suggestion that WILL make an improvement on reliability and that is high pressure injection moulding for the heads and cyls.

Don't get your statement about high pressure injected moulded heads and cylinder? The cylinder are machined out of a slingle billet of steel.. what wrong with that?

Cheers

Jack

Through bolt failures is hardly a Jabiru only problem … this was happening on aero engines before Rod Stiff ever consider building an engine and still is.

In any case, Jabiru has done quite a lot to fix these failures over the past 18 months which has reduced the incidence significantly. They have modified the engine in a number of ways to engineer out the problem and reduce the propensity of fuel detonation, which is the primary cause of through bolt failure in Jabs.

Take a read of the attached “Case Check” in Jabachat for some helpful hints on maintenance procedures, albeit 99% of tool boxes won’t have the tools do the 200 hr checks on the through bolts as prescribed… you will most likely need to enlist an L2 or LAME to perform the checks.

http://www.jabiru.net.au/Jabachat/Jaba%20Chat%20August%202010.pdf

Cheers

Jack

Hi Ian,

Thanks for this ... Rod did make mention of the discussion last year and was aware of the road blocks.

However, after talking with him today he seems to think there is an alternative or a new approach to get this over the line.

It may be best you have a chat with him directly and talk though his thinking and test it with you own understanding and help him shape it for the RAA Board meeting?

Cheers

Jack

Michel,

Did you see the Aug Jabachat ... attached link

http://www.jabiru.net.au/Jabachat/Jaba%20Chat%20August%202010.pdf

Cheers

Jack

I spoke with Rod Birrell (Victorian RAA Board Member) today and I asked where things are in terms of the introduction of a Plain Language Weather Reports for recreational pilots.

Rod said, he is very enthusiastic to make this happen and will champion the issue on behalf of the RAA membership.

He said he intended to table the motion earlier but the RAA elections had been a personal distraction which slowed things up. Never the less, he said, he will be tabling this at the next board meeting in a couple of weeks.

Rod seems to think there is a reasonable opportunity to develop an interim solution around the legislation to move this along with some pace, although it will still take time relative to many things involving bureaucracy.

He said, this work sits mainly in the domain of the RAA Operation Managers but he is very supportive and prepared become directly involved in this project to help drive the change.

If any of you out there feel supportive of moving to a Plain Language Weather Report it wouldn’t hurt to inform your state board member to help motivate this along… just drop them a short email.

Rod said that he will get back in touch with me as soon as he has introduced this at the next Board meeting and let us know the next steps.

In my view, if this change can make flying safer through reduced complexity and clearer information we have had a win.

Cheers

Jack

G’day Tomo,

Yes you’re correct, oil does “wear out”.

Essentially the lubricant is made up of two parts, one being the base oil and the other the additive system. The additives do a number of things to enhance the lubrication performance in terms of anti-wear, soot and viscosity control etc etc. Over time the additive system gets over loaded (soot, acid etc) and the oil itself begins to oxidise and break down .. therefore oil (lubricant) “wears out”.

However, the response posed by BlackRod in terms of lubricant dwell periods being safe at the manufactures recommendation is something I would assume to be spot on… I would expect the OEM’s recommendations would have been supported by quality data from oil and wear metal analysis over an extended period of time.

Not withstanding all of the facts produced by the OEM... I say, oil and filters are cheap and I’m a 25hr oil man.

Cheers

Jack

I see not only has Lowrance has pulled the pin on the manufacturing of the 2000c but they are not providing update services on the Jeppesen map data... no reason given other than there is a "situation" ... which i think is code for don't sue us yet!

LEI Extras - Jeppeson Database Updates

It's not right these guys can promote and sell a product and then dump it without warning as well as continue to allow their distributors to sell the old stock knowing there is no software map back up.

Shame on Lowrance

Jack

I also went along to Oshkosh and sat in on almost all of the electric workshops and discussions .. also met and spoke with all of the manufactures about their products.

The Yuneec guys were much more advanced in terms of a commercial release and their products look quite good. They had a 40kw motor mounted on a wall stand and I got to have a go at playing with it through the power and speed range .. the most interesting thing was how quiet and smooth it is.

Without exception all of the manufactures are waiting for the next step in battery technology .. most seem to think that Li -Air will be the next gen to provide the energy density they need. The problem is the cycle capacity is only around 3 or 4 cycles compared to 1500-3000 with Li-Po. I think the technology is already here but they need an engineering solution to sort out the cycle performance.

Never the less, the whole programme is real and alive using Li-Po and they are making great strides .. if I was a betting man I would say we will see a real commercial solution in the next 5 years that will meet the reliability and durability we will need for avaiation.

Very exciting times to come.

Cheers

Jack

Dont read too much into the SG as avgas has a technical range between 0.690 and 0.760 ... Oil Co report the typical SG in their specs... the actual SG will vary from time to time and always does.

Cheers

Jack

Thax Ian ... Very powerful reminder ... I have just shared this with some firends and family.

Jack

Modest Pilot,

Here's the technical specs and Material Safety Data Sheets off the BP web site for Mogas ULP 95

BP Australia - Technical Data Sheets

BP Australia - Material Safety Data Sheets

Just select Road Fuels in the drop down box.

Cheers

Jack

Jab already have a fuel injected multi port system which is sold to Israel to power UAV’s… the system is not available for manned flight and is not the be all end all answer some may think.

Comparing any of the older Jab engines to the current engine is no comparison .. whilst the Carby and induction system needs improvements (which is under redevelopment) the engine has made some great strides in the last 2 years to improve cooling, lubrication and detonation management.

Cheers

Jack

Spot on Brian ... 90% of these problems are over heating issues.

The magic numbers is to keep the EGT below 1250 deg F and CHT in the middle of the green at around 275 F ... need to make sure the carby jets are fat to keep EGT's down and that air flow through the engine cowl are correct .... tooo much pitch on a prop will kill them very quickly too .. as you said good airspeed and plenty of air flow works wonders.

Cheers

Jack

Hi Deadstick,

The earlier piston had convex domes .. you have flat but these are not the latest pistons.

Cheers

Jack

G'day Deadstick,

You may want to check on what is current with Jab as there has been many updates on the new top end that has made a significant improvement on engine durability.

They have fitted new pistons with more ring grove clearance and a bigger slot for the oil drain back, new cyclinders, new heads with 50% more fins along with a new shape to the combustion chamber and new over head gear and push rods ... the new pistons dont have the notch on the crown (they have also removed the centre dome on the crown) and only have a tit over the piston pin mount which faces the front (prop)... I guess what I'm trying to say is there are many changes to the current engine that you can retro fit onto your older engine and dont use the old bits to compare what is now available as standard from Jab.

In my view the new engine bits has made a good engine great.

Cheers

Jack

Guys,

Hate to say it, but if you have fitted the pistons with the notch to the back (fly wheel) you have put the pistons in wrong way around .. the Jab manual is quite correct.

Forget about rotation for the moment and fit the pistons as per the manual... try marking the centre line of the piston on the underside of the piston crown ... you will see the pin is off set to the centre line.... now assume the rod part way down the power stroke 90% ATDC, now draw a line through the big and little ends ... you will note that the line between the two centres will intersect with the centre line you have marked on the underside of the crown. If you put the psitons the other way around it will be way off set which will drive the piston down the bore sideways during the power stroke.

Cheers

Jack

I have the MRX in my Jab 160 and it works just fine ... you do rely on others having there transponder on but it has picked up many aircraft before I have had a visual.

It's another set of eyes to help you find traffic and worth ever cent.

Cheers

Jack

Hi Chris,

I exchanged a few notes with David Birrel who said he would raise the issue with the RAA board ... so far no feed back at this stage but I will follow my end and check progress and let everyone know.

Cheers

Jack

Hi David,

May be I can answer some (not all) of your very good questions re premix and the impact on fuel burn.

Firstly the calorific value of fuel is actually increased owing to the higher density of the two stroke lubricant (approx - fuel 0.7 – 2 S oil 0.88) when blended… additionally there is very small increase in viscosity, which does have an effect on the flow characteristics of the fuel through the jets. The energy value will remain somewhat the same either premix or injected and at a ratio of 50:1 the viscosity change is really very very small … the viscosity is more affected by heat variations.

Just as a matter of interest … generally speaking, as the ratio of 2S oil increases you see a corresponding increase in fuel energy values and usually peaks at around 16:1, which is very rich .. however there are some poor side effects, these being a drop in Octane performance, plug fouling and coaking etc.

Pre-mix has been around long before oil injection and is a reliable method for lubricating a 2 stroke engine … there has been a few exceptions, but mostly premix is considered a very safe method of lubrication.

The main thing to be concerned about premix is its use by date … the shelf life is very short and you will see an accelerated drop in lubrication quality and octane when stored. It’s always best to use fresh.

Btw … Cetane number or index is a diesel fuel measurement which refers to combustion ignition delay and nothing to do with petrol fuels energy.

Hope this helps?

Cheers

Jack

Well done FG ...