Powerin

In this thread I did a bit of a count through the RAA register. There are 755 Jabs registered (obviously with Jab engines). Counting the airframes that I was pretty certain came standard with a 4 stroke Rotax in them, I came up with 690 Rotaxes. Of course there are many more airframes that would have either of the engines. For instance, I assume most, but not all, Zenith CH601s would have Jabs, but most 701s probably have Rotax. The register shows that there are far more Jab airframes than any other sort, but that there are *probably* a similar amount of Jab engines to 4 stroke Rotaxes in Australia. There is no direct evidence as the register doesn't show engine type. If you counted 2 stroke Rotaxes, Rotax engines would far outweigh Jabs in total number.

I know of one 80hp Savvy. The owner was very happy with it, especially the economy and the wider availability of fuel (regular unleaded).

This is absolutely true, but is it really a fair statistic? We are responsible for a fairly large part of the Earth's landmass and by extension a large percentage of the atmosphere. The USA is of a similar area but has 14 times as many people. Even if they emitted 25% less per capita than us they would still emit an order of magnitude more C02 than we do for a similar proportion of atmosphere. To take the argument to the extreme, we should really crack down on the bases down in Antarctica because I bet their emissions per capita are off the scale. But in reality, of course, the Antarctic's total emissions are minuscule and so make the per capita metric meaningless. Surely something like a per square kilometre metric would more meaningful. Applying this to Antartica you would come to a figure that truly reflects it's role in world's carbon emissions...minuscule. As someone who tries to maintain a logical and balanced view of human induced climate change, this statement appeals to me as a strong reason to do something. But when such things as per capita figures and accusations of being in the pockets of mining companies start getting thrown about the sceptic in me comes to the fore. Sorry about the thread drift :p

I wasn't making any assumptions. I'm just saying the production of ethanol requires a reasonable input of energy and various chemical compounds, much of which comes from finite resources. If you trust Wikipedia as a source (I do mostly) here is the article on the energy balance of ethanol.

This line is often trotted out to try and discredit any information that opposes pro climate change science. I don't buy it because it pre-supposes that money is always the driver and therefore the motivation behind ALL pro climate change science is as pure as the driven snow. A lot of the green philosophies are based on deeply held beliefs and ideologies that are often pursued with religious fervour. Never underestimate the power of ideology...from both sides. Ethanol (or vegetable oils) is just another form of solar power, but it is conveniently stored in liquid form. I don't have a problem with using food producing areas for ethanol, at the moment, because if there was a shortage I wouldn't be getting such low prices for my grain. The problem with ethanol is that it is no more sustainable than fossil fuels. To grow grain or cane as cheaply as we do we use fossil fuels in our tractors (which could conceivably be replaced by expensive vegetable oils) , the crops are fertilized with products that are manufactured from non-renewable resources....Phosphorus fertilizer comes from mined phosphate rock and Nitrogen fertilizer is mostly made using natural gas, chemical sprays come from petro-chemicals. Until we come up with environmentally AND economically sustainable ways of growing crops (and feeding the world if it can afford it), using ethanol just replaces one form of unsustainable energy with another.

That, Nev, is the right question! (with apologies to "I Robot")

Easy! Jab just needs to set up a retuning station at each airport so they can tune each Jab that passes through to local conditions. Problem solved!

Well done Cory! I just hope I remember my training and procedures as well as you did if it ever comes to the crunch. I'm curious, and perhaps others might like to comment as I'm not a mechanic: thinking about cause and effect I'm wondering if the root cause of Jab's problems could be the induction system? I've read many, many pages of people struggling to even out EGTs in their Jab engines. If detonation is indeed the cause of through bolts breaking, would cylinders consistently running too lean contribute to this?

Had similar to you David, 15mm in two 5min storms and 1cm hail....but it was all round. Enough for me to run around putting vehicles under cover. It was probably the same line of storms as they were heading SW from us.

Savannah's have flaperons which are divided about half way down each wing and are offset from each other to create washout as the wings themselves don't have any. I think the inner part of the flaperon is lower than the outer which would be similar to a slightly lowered conventional flap. Savannah owners could correct me. If my memory serves correctly, lowering a flap increases the angle of attack of a wing, which means the section of wing with a lowered flap should stall first.

If that is the intent of the RAAus then they should write it in the rules. Can an Ops manager override the rules (see my post #5)?

But in this case that shouldn't apply. If you pass a flight review for a PPL it will be accepted as a valid FR for a HP RAAus certificate (according to the rules). Interestingly the rules say nothing about flight reviews for CPLs (or ATPLs for that matter). I know an ag pilot that's been caught out with that (ie RAAus not accepting it).

My take on the rules is that a PPL BFR will be accepted for RAAus, but only for a high performance endorsed RAAus certificate. You will still need to do an extra BFR in a low performance aircraft for a Low Performance endorsement. This is from the RAAus Ops Manual Section 2.07, 5 (i): If a certificate holder has within a period of two years immediately preceding the flight, has passed a flight check for the renewal or initial issue of a CASA approved Private Pilots Licence, then the pilot is taken to have sufficiently completed a flight review on high performance aircraft only. This will only be accepted upon receipt of a copy of the logbook entry validated by an Instructor.

Warning- thread drift... I'm somewhat uncomfortable with fuel tanks in the cockpit space, but that's where a lot of RA aircraft have them (or header tanks). Is this a misplaced fear? Are there any stats (in any class of aircraft, GA or RA) to suggest that fuselage tanks are worse than wing tanks for crash survivability? Are any tanks worse than others - plastic, metal or fibreglass? One I have read about is the Piper Pawnee which had problems where fibreglass fuselage tanks split in accidents. They were later recommended to be fitted with rubber bladders or retrofitted with wing tanks if I recall.

Off topic- There is a golden rule born in the distant Internet past from the days of Usenet newsgroups: Don't feed the Trolls

I bet this would be the most difficult and time consuming part...especially the deciding what is needed bit What would be your rough guess David? Under $50K?

I, for one, would be in favour of the RAAus spending a reasonable amount of money on this sort of system. As well as providing timely data which could allow targeted safety initiatives, they should have systems in place which streamlines pilot certification and aircraft registration and certification. Something like that could automatically flag problems such as pilots without medical declarations or aircraft without valid certificates such as we have seen lately. Even CASA audits should become easier. I dare say a custom system like would be expensive to implement in terms of software development, hardware and staff training, but it would have the potential to save money down the track in terms of efficiency, staff numbers and safety outcomes. EDIT: having said the above, transferring the existing data to a new database would be non-trivial if the aircraft register is anything to go by. When you start going through the register you see it is full of inconsistencies. Take a Savannah for example, manufactured by ICP. In the register Savannahs are listed as having the following manufacturers: I C P I C P Savannah ICP ICP Savannah ICP SRL Icp Srl ICP XL VG Savannah This is understandable as it probably depends on what the owner wrote on the application, who entered the data, and how much aircraft knowledge they had. A human can probably tell these are all the same manufacturer, but to a computer database the Savannah would have eight different manufacturers.....which is a problem if you're trying to get meaningful stats out of a large database.

Very roughly, counting the aircraft that I'm pretty certain would have Rotax 912s, I get 690. That's not counting any models that would almost certainly have a proportion of Rotaxes such as the Zeniths. I've only counted the 27 Lightwings that have 912 in their model number (do any Lightwings have Jab engines?). So there are probably several hundred more 912/4s and a similar number of extra Jab engines that are not in a Jab airframe. My impression is that there would be similar numbers of 912/4 and Jab engines but there are no definitive stats to back that up. I guess the majority of the 2 strokes would be Rotax?

I was just presenting the numbers, not taking sides. I wasn't sure it was accurate to say there are more incidents etc with Jabs because there are so many more of them...but looking at the figures I have to say it probably is a valid argument. Looking through the register I get the impression that there might be a similar number of Rotax four stroke engines to Jab engines. Even in my list above if you count the Tecnams, most of the Savvies, Foxbats and a fair few of the Lightwings, Zeniths and Skyfoxes you would have well over 300 Rotax 912s. With the RAAus register only (publicly) having rego, date, manufacturer and model, there are very few stats you can get from it. I think RAAus keeps a record of pilot hours flown don't they? But not hours of aircraft types.

I don't know enough about the different manufacturers...but I see now there are another dozen or so Drifters listed under Maxair as the manufacturer.

You often see the claim (as I did again today) that the reason Jabirus feature as often as they do in faults and accidents is because their are so many of them. So I thought I'd do the exercise and work out how many there actually are on the RAAus register. I did this by copying the aircraft register from the RAAus website to a spreadsheet and sorting and counting by manufacturer. The register is a bit inconsistent in how aircraft names are entered so the counts may not be exactly right. And the verdict is...Jabirus are by far the most popular aircraft with 755 out of 3414 on the register or 22%. Other manufacturers of note are: Airborne (trikes) - 234 Aerochute (powered parachutes) - 215 Tecnam - 132 ICP (mostly Savannahs) - 125 Thruster - 115 Skyfox - 105 Austflight (Drifters) - 98 Howard Hughes (Lightwings) - 97 Zenith/Zodiac - 76 Aeroprakt (Foxbats) - 68

Bad luck Solomon...but onward and upward! If you were welding I assume you have a steel frame. Others here with experience might like to comment....would the strength of the steel frame be compromised by a fire? Also it may have warped a bit?

I was lucky enough to have a choice between two different types to train in. I chose the one that was easiest to fly (or more accurately, flew as a well designed aircraft should ), even though it was more expensive. I wanted to discover how the controls worked and learn to fly in various conditions first before I started dealing with the idiosyncrasies of aircraft design. I'm happy with the choice so far. It will be interesting to fly different types in the future (taildraggers are definitely on the list), but honestly I love flying an aircraft that flies as an extension of myself. As an aside, flying with my instructor in his Rv-7A....that is really an aircraft where you just have to think what you want to do and it does it. Exhilarating!

Cut them off? The last time I looked at the rules aircraft on a straight in approach must give way to aircraft already established in the circuit.

Motz, You have had an influence on me. Even though we've never met. From all you've written in forums and even on chat (believe it or not) you've been someone whose opinion I respect. As a student I have taken a lot you've said here to heart...either by reinforcing things I've learnt, or stuff my own instructor didn't tell me. When you talk aviation you talk safety and promote that culture. If a guy like you can't instil a culture of aviation safety in those around you, well, I'm not sure anyone could. What else can you do? Cheers, Peter