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ianboag

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Everything posted by ianboag

  1. That is super-cool! I went for something minimalist on the weather report front. What system are you driving it with?
  2. I moved on from PEMET. Thought it would be good to have a simple weather station for any old airstrip. Basically all one would want is a (reasonably) current METAR plus a webcam or two pointing in a useful direction. Here in NZ we have lots of situations where you should be able to see some hills or whatever. Something to give you a bit of a handle on the cloudbase. So I strung it together - the METAR equiv needs a $200 Jaycar weather station plus a pretty-much-dedicated any-old-PC with a cellular modem. Not a lot of $$$. Then you need to add a few (VGA) webcams - I haven't quite figured it all out but they cost diddley and VGA resolution is fine if you just want to know about what the sky looks like in various directions. I'm part way there (pics - vanity - are dummies of the final size) at bgy.inspire.net.nz. I can think of lots of unbusy airfields in NZ where the likes of this would be cool ... Setup cost is a bit of change out of $1k (depending on the pole that things were mounted on) and running cost like $15/mo. I'm happy to share the how with anyone who might be interested. Ian B
  3. There is no way that a coolant-heated butterfly could change the induction air temperature by any meaningful amount. It's basic heat transfer stuff - there's just not enough surface area or temperature difference. It doesn't matter how many hp are warming the coolant. If some ice forms on the butterfly it acts as an insulator, so the temperature of the butterfly goes up which melts the ice enough for it to detach. That doesn't need a lot of kw - think of the difference between heating your bedroom with a couple of kw or just using a 100w electric blanket in your bed .... I'm talking about the physics, not the FAR 23 thing. The Merlin probably wasn't FAR 23 compliant either ..... :-)
  4. Not really. There are a lot of 912s flying round with zero carb heat and/or electric/coolant heated jackets on the manifold downstream of the butterfly. The aim being not to heat the air but just to melt ice off the manifold wall which of course needs far fewer kW and does not significantly change the air inlet temperature.
  5. The experts on the field (every field has them ....) frowned very strongly on doing this when I suggested it. Something to do with "just two points of contact" and "accelerated wear" etc. I've had a chat with the LAME who did the job - basically he didn't know much about this sort of thing and used my job to learn ...... :-( I also found out that Jab offered him the old-style hinges with the caveat that "they will wear out". They would have used the existing holes and only lasted another 1000 hours or so. Measured in years that might be as long as I do. But I was not asked about it. Doing business with friends is a bad idea.
  6. Actually - although no doubt Ian B would oblige me if asked - I don't have access to the site anyway.
  7. Thanks. Sorry about that. Have seen this problem before around midday/midnight. Have fixed it in some places (see earlier posts) .... Yes it does know about daylight saving. Local time is a Linux/PHP function and incorporates DST ... don't ask me how :-) I just had to specify the areas for every airfield. Can't guarantee that it always changes exactly on the day - I noticed with the NZ ones that it was sometimes a day ot two late ..... can't say I've ever looked specifically at Oz DST's. I have decided to end support for this page. I gave (as in $0.00) all the source code to the other Ian B .... It's a fairly large pile of PHP, but any competent PHP cutter with a few hours spare time should be able to fix it. I would provide said cutter with whatever background info she needed.
  8. OK - it was 40-odd hours for the hinges .... seemed a tad OTT. Perhaps I'm out of touch?
  9. I just had the (six) aileron hinges and (four) elevator hinges and elevator cable replaced by a LAME II think that's about the same as an L2). I'm curious to get some feedback on what would seem like a reasonable estimate for the number of hours that might be involved.
  10. ianboag

    Aileron flutter

    They weren't ... :-(
  11. ianboag

    Aileron flutter

    The other advantage of using Jab ones is that (hopefully) the holes are in the same place as the existing hinges, so the flock bed they sit on will be the right size and in the right place .... it all gets quite a bit harder if this is not the case :-(
  12. ianboag

    Aileron flutter

    Dafydd. As always, a sensible comment. I respect your views. I know about electrolysis. However ..... This was done as a short term fix for about 6 weeks so we could get on with test flying. The relevant authorities are aware of it and of what/when happens next. The rudder hinges were replaced with new factory ones when I bought the plane a few years back. I now have some new hinges (aileron and elevator) from Jab that I bought at the same time as the new aileron cables. I'm sick of being an amateur mechanic, so they will be fitted by a LAME in about 4 weeks when I am over visiting family on your side of the pond. The original pins were indeed cadmium plated spring steel. The new pins look more like stainless (?) - they certainly aren't yellow. Factory parts and all that so one has to assume it's the right stuff ....
  13. You'll find a bit more background at http://www.snopes.com/politics/quotes/pigeonchess.asp. Feel free ....
  14. As a wise (r than me) person once wrote. "Arguing on the Net is like playing chess with a pigeon - eventually the pigeon will knock over the pieces, crap over everything and fly off to tell the other pigeons that it won".
  15. There is an STC for putting an 80 into a much older Jab. Done by Tony Grills. The one at YCAB was modified with an EO. There is no STC for a 160 Rotaru.
  16. Nope, it was not an STC. An Engineering Order from a CAR35 which only applies to the specific aircraft it was done for. The plan was to get to an STC .
  17. The other mod required is to move the battery down the back and all the nose-heavy thing goes away. It wasn't too hard to do here in the NZ regulatory structure, but in the Oz version it would be quite a bit harder. We have just finished the test flying.
  18. ianboag

    Aileron flutter

    Understood. I had the drawstring tied in the rod end hole and couldn't see any other way to attach it securely. Losing the drawstring off the cable part way through the exercise would have been a real bad hair day. One of the cables went in smoothly - the other one had the nogo problem. I had difficulty extracting the old one on that side, but I figured that as I got it out eventually I would get the new one in eventually. Didn't happen until I slimmed the rod end down a bit. So I have now acquired a new skill (inserting Jab aileron cables) that I will hopefully never have to use again :-)
  19. ianboag

    Aileron flutter

    Replaced the aileron cables - problem is fixed - now there is no flutter/buzz/vibration. The stick feels like the aileron cables are running in glue - so cable tightness and friction are obviously significant damping factors. Pulling one of the cables was a bit hard because the hole in the wing was a tad small - it was necessary to grind down the rod end to pull the cable through. That was the old (sad) rod end which we then threw away.
  20. Ozrunways and Airnav Pro and the Sentient app are super cool - but the reality is that pretty much all phones and tablets are not real flash in direct sunlight. It is something of a mission to use them in a bubble-top or clear-roof aircraft - the "on the pilot's knee" thing just does not work. Ditto for solutions using car GPS hardware. Generally there are no worries in a cockpit with a roof .....
  21. ianboag

    Aileron flutter

    One will have to give it a whirl I guess. In the GA world this would have been an SB if not an AD ......
  22. ianboag

    Aileron flutter

    Not a silly question at all. This is a far-from-new aircraft (belonged to the Adelaide Soaring Club). The problem has not been noted up to now but in my ownership I'd be surprised if it spent 5% of its time over about 95 kts. Having sat there and watched it, I presently go with the aileron flutter notion. I can echo your "not all the time" comments, although my pilot tells me that before we lifted the ailerons it was all the time .... Sometime after Christmas I will get to change the cables and we'll see where that leads ... hopefully to a full resolution of the issue.
  23. ianboag

    Aileron flutter

    We lifted them a bit more than that - used up all the adjustment on the cable - and it reduced the flutter considerably. Funnily enough if you read up light aircraft and aileron rigging/flutter everyone talks about droop not lifting. Go figure. Anyway we have looked at the amount of aileron cable play on a couple of other Jabs on the field. Both were appreciably less than what I have, so we expect that the new cables to sort things.
  24. ianboag

    Aileron flutter

    Not that I was aware of ..... any time one got over 100 KIAs things rattled and buzzed. I did not identify anything as incipient flutter. I wasn't in the habit of flying at over 100 KIAs because that was over 3000 rpm and I couldn't be bothered with everything sounding like it was working so hard. The slop in the aileron cables is for real so that will get fixed. I can't see how the Rotaxification has anything to do with it.
  25. ianboag

    Aileron flutter

    It wasn't me flying - the plane is having some hours flown off after a mod (changing to a 912ULS) and it's the test pilot who tells me this. The problem did not go away when the hinge wires were replaced, although that did get rid of just about all the hinge slop. So we're doing the cables too. The 912 thing has worked out well so far, although both time and cost estimates were ludicrously optimistic as one expects in aviation ......
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