ianboag

a general approach It's been so long since I last looked in this thread that I can't remember if this point has already been made but here goes ...... If you buy one of the many no-name Chinese car GPS's they all (that I have seen) have a facility in the "Settings" section to specify the "Navigation path", so you put all the OziCE stuff on an SD card then just point the system at it. When you select "GPS" off the device menu up comes OziCE. Changing it back to car use is just as simple. No "unlocking" necessary. IB

Me too I'm a Kiwi and was returning from China in 07 with a detour to Bundy. I rode the tilt train up from Brisbane. Where else could you collect a tilt train for your "been there done that" portfolio? I had been in touch to ask about a visit and was a bit surprised when Rod turned up as my guide. I guess it's the sort of thing the staff encourage to get the boss off their backs :-) Anyway it was very pleasant - nothing was too much bother - and I found it all good stuff. Cheers IB

So I assume the appropriate thing is to leave it untranslated?

Had a quick look at the site today - can someone help me with the CRAVN bit of <YLIS/CRAVN/YSBK> - somewhere in NSW I suppose IB

Problems and solutions Major. You are suggesting a design change and it seems a reasonable one. There have been other suggestions along those lines from time to time eg using a taper/key approach like lots of auto engines, counterboring the crank etc etc. Today's problem though is what - if anything - should be done to the current configuration to make it safer. IB

This was all from about 2007. What he says is this is a clamp joint and there is heaps of scope to increase the clamp force. Hard to argue with. At the time Jab were saying 18 ft-lb for the bolt torque - they upped it to 24 and he is saying 30 would be fine based on normal sums about the bolt strength. More clamp = less ability to wiggle and chance of breaking bolts. I think all one needs to do is crank the bolt torque up to about 30 ft-lb (lubricated) and forget about Loctite. Then you can (meaningfully) check the bolts as often as you want to. There are no locking issues - the bolt is not going to unwind from that level of tension. If you are worried about that, just put a paint blob on it - if it unwinds at all you can see. If it relaxes, one will be able to detect that and either re-torque it or (more likely) replace the bolts ... This is pretty much what was done by Assessco and as far as I know there have been no issues with any of those engines. Go figure. IB

Going back a bit .... Worth reading .... Contrails ! Jabiru flywheel bolts

Another 10c worth The bolts/dowels broke. In previous cases, the bolts have broken just where they emerge from the crankshaft. I believe this latest case is the same. When the bolts break like this, the crank gear is no longer connected to the crankshaft. The engine goes round a couple more times (camshaft stationary) and there is clattering and banging as valves hit pistons until it stops. The bolts break there because the flywheel slips and bends them back and forth. The failure comes from fatigue from all that bending. It means there is not enough clamp to hold the flywheel. The dowels were never meant to be drive pins taking the full load - the role of dowels in a clamp joint is just to carry the (relatively) small load that might happen if the frictional clamp forces are exceeded slightly. The bolts break because they are loose. End of story. This is all pretty standard clamp joint stuff not restricted to Jabiru flywheels. Bolts break from fatigue when a joint is not sufficiently well clamped. Assuming the sandwich was all torqued up properly in the first place, this means that either the bolts have unscrewed a bit or the sandwich they compress has relaxed ie the bolt heads have "imprinted" a little bit. We will never know ... because ..... The factory specify the use of the mean green 620 Loctite. This stuff is so good that even if the sandwich has relaxed a little you will not find out by putting a torque wrench on the screws. "Unscrew" is not going to happen because the bolts are firmly glued into the bottom of the hole. If the bolt tension REALLY needs watching, the Loctite has to go. Then the screws can be meaningfully checked (untorqued/retorqued) at whatever interval floats your boat. I've heard opinions from non-ignorant people who believe that grease is a better thing to put on than Loctite. I did hear it said (rumours from years ago are always worth quoting) that back when all the bolt/dowel hoohah first happened, the man in Hamilton who became the default Jabiru doweller for NZ would only use grease on the bolts. If an untorque/retorque sequence is not possible then nobody will ever know how, when or if the bolts lose tension over time. We will only know after the fact if they break ....... Replacing the bolts every 500 (or 200 or 600 or whatever) hours seems harmless enough. Inspecting them every 20 or 50 or 100 or whatever hours with a torque wrench is a waste of time. For us private bugsmasher people the 500 hour replacement thing is every four or five years. It's not a big job and the bolts are not expensive. Go figure. Ian B

A few posts ago Ian said ... I believe that Champagne Flight planner contains PLM code too. The problem with doing it at the PC end is if BOM makes a format change in the data. They are unlikely to change the content (so any changes will still be human-readable) but a format change might kill it for a decode program. If one does it on the web this is not an issue because the provider only has to adjust the code in one place once. Not to forget the other benefits about how you can get off any old PC or Net-enabled mobile phone ..... IB

I know REGULAR pilots who struggle with TAFMET gobbledygook .... and go to the regular weather site or Sky TV (our Foxtel) because they understand it. Incidentally if it's going out to tender, make sure I get a set of dox. The CAA's weather guru conceded that pemet.co.nz was "one of the better PLM sites he has seen". I asked him to point me at some of the better ones so I could see what to learn from - and pemet became "the best he has seen". Notwithstanding my urges to stay modest, I haven't seen a better PLM site yet. I accept that there are a few more things I should do to pemet.com.au but there's a "round tuit" problem. I also do things I get paid for - we have to eat - I have to keep my Jab in the sky etc etc :-) What's the story about the other PLM from Tooradin or Tyabb ... ?

If it's any help - you might like to look at how the NZ CAA and Metservice handled it on this side of the ditch. It took rather more than a submission from RAANZ to make it go. The Aviation Industry Association eventually took it up with the CAA Director. Metservice were EXTREMELY resistant to the idea - an estimated development cost of $200k being quoted at one stage. CAA blew all kinds of unhelpful smoke at it. Perhaps CASA and BOM would be much more reasonable. If you go to metservice.metra.co.nz and use my login/password <S899> and <8/08/05> you get the NZ equivalent of the BOM site. If you pick a forecast area, you will get (among other things) a button for "plain language". If you click it, you get a disclaimer about a page long that says the sky is falling down and Metservice has nothing to do with whatever the shonky thing is you are about to connect to. Then you get a translation (run with the same engine as pemet.co.nz uses) And of course it's not hard to find individuals in CAA who think my PLM (plain language met) site is great and they use it personally. Here are some of the reasons CASA/BOM might never produce PLM for you. - PLM is not ICAO certified (there is no ICAO spec for PLM so it can't be done). - Real pilots are all fluent in gibberish. - It would cost too much and there is no budget for it. Cheers IB

Lynn Matteson on the yahoo jabiruengines group has some sort of direct fire ignition plus a ***** TBI on the Jab 2200 in his Avid. He's a bit of a serial fiddler, but seems to (a) know what he is doing and (b) like his hardware setup.

Someone could even throw a small no of $$$ at me to tidy up the last bits and pieces :-)

The MGL fuel flow setup is on redirect page. Instrument plus transducer is $NZ550 (inc 12.5% NZ GST) which makes it $A450 give or take. There's probably an Oz agent too.

MGL do fuel flow stuff too.

Not to forget the MGL stuff - Odyssey and other EFIS panels all feature autopilot outputs. I had a Trio in my J200. All worked like it was supposed to but I didn't really fly enough long legs to justify it. Wot? Justify? In a toy aeroplane? Wash my mouth ...... IB

It's alive again. Someone went into the office and rebooted the server. I'm still in Southern Peru.

Ugh No the address has not changed. I´m in Cuzco (Peru) heading for Macchu Picchu and it´s Sunday in NZ so noone is in the office in NZ. It would appear that the server PC has fallen over. I suppose I should host the thing with a real ISP that isn´t subject to these outages. Sorry :-( IB

Not so. I went to Metservice in Wellington (they have tacked my PLM on the end of their standard page) and talked to some of the forecasters. They write this stuff down cold. There is no initial English->jibberish conversion. I would guess that BOM are the same. Clever folk! IB

I have now. Rule Part 175 is something different. My error. (1)(h) the latest editions of the aeronautical maps, charts and other aeronautical information and instructions, published in AIP or by a person approved in writing, .... . (3) An operator must keep a completed flight preparation form for a period of 6 months. (4) An offence against subregulation (1), (2) or (3) is an offence of strict liability. Note For strict liability, see section 6.1 of the Criminal Code. I must look into this "flight preparation form" thing - we no doubt have the same rule in NZ. Then I suppose I should toddle down to the police, fess up and do my time like a man for repeated criminal transgression of sub-reg 3. All those Sunday afternoon local flights in my Jab and never a flight preparation form to be seen .... how unsafe is that! I guess 1(h) covers AVMET. The pemet page is just a web page translation from gibberish to English. If I were more of a linguist I could have done one in Spanish or French. I am not a weather data provider - that requires certification and approval by a person in writing. As an aside, if CASA/AirServices are anything like CAA/Airways, they wouldn't know where to start in certifying or approving plain language AVMET. There's no CAR or ICAO standard or anything else for it so they would have to make it all up from scratch. Think 5 years if they decided tomorrow to do it. Alternatively they could just do it - like in Canada where the TAFs/METARs from NavCanada (the AirServices equivalent) come as codes and optional English. Fair enough. I didn't know that. TSO C129 defines the gear, but who regulates/licences the maps? The only GPS's I have ever seen are the non-TSO'd units (Garmin x9x) with the Jeppesen-crafted skeletal moving maps and airspace pictures. You find them in lots of recreational aircraft. Being non-TSO'd they are never used for any function related to navigation except as a backup in case of chart failure [see CAR233 subregulation 1(h)]. :-)

I'm a 65-year old foreigner. When I started this I had no experience in programming for the Web. I have created what seems to be a reasonably robust AVMET to plain language translator. Noone has paid me anything. One of the reasons I did it was to teach myself PHP. So how hard would it be for AirServices or BOM to do it "properly"? Not that there are any significant bugs in pemet.com.au that I presently know of ..... IB

Actually the present ICAO-standard pig latin is much newer than that. Prior to (about) the late 60's it was all done with numerical codes. What we have now was released as being a huge improvement. Go figure .......

At the pedal where what you see is "pedal force" -> hydraulic pressure = "pedal force"/(master) piston area. At the pad -> "squeezing force"=hydraulic pressure x (slave) piston area. Braking drag is proportional to squeezing force. If there are two slave pistons in the circuit there will be twice as much "squeezing force". You could achieve the same increase in squeezing force by just having a bigger (diameter) slave piston - even with the same pad area. But - what you need extra pad area for is to dissipate the extra braking energy (heat) from the fact that you are slowing down faster. So it makes sense to double up the pad area to dissipate the extra heat. However there will be some heating issues because you don't get to double the disk area .... One would expect much faster initial braking - for the same lever pressure - but some possibility of fade later. IB

Nope. Same pressure, larger area = larger force. It's FORCE at the pad that determines the friction force. So same pressure (force on the lever) will generate more braking force with two caliper sets than it would with one. Nope again. Second caliper set will result in more friction force than just one caliper set = more braking = more heat generation = greater possibility of heat-induced fade. It will brake harder but maybe not longer. Better heat dispersion is a good idea because there is a whole lot more to disperse. Final answer - do two caliper sets give better braking than one? Yes. If in doubt, just stand the question on its head - if the pad area was halved would it make things worse? Of course it would .....

Going back to the physics of all this, I would expect two sets of calipers to be better than one ... here's why ... If you put two bodies into contact, there is a friction force that acts to prevent relative motion between them. This friction force is (the amount of force pressing the two surfaces together) times (the friction coefficient between the two materials). The friction coefficient is a property of the two materials involved. So if you have one set of calipers there will be a braking force that is proportional to the squeeze force exerted by the calipers. Two sets of calipers = two lots of squeeze force = twice the braking force. So it should all work ... However, twice the braking effect will give twice the rate of heat generation at the pad/disk level. So the disks could become very hot which could stuff up the disk <-> pad friction. Also there are the points that have been made about water in brake fluid etc So - on the one hand this - on the other hand that. I would expect INITIAL braking to work a lot better with two sets of calipers compared to one. I would expect the benefit to taper off some as the disk heats up.