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RFguy

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Everything posted by RFguy

  1. further.... think of the length of the region of flattening (usually in middle 20mm I think ) , this covers all the strand bundles because of the helical wind... IE you are getting flattening in all the bundles and a high proportion of all the wire in each bundle- this is not simply isolated broken weak strand. It will be interested to do a load test on this cable, see how far it is above the normal tension that it lets go. In radio masts, we'd use this size guy cable for about 500kg working.
  2. Control cables really do wear out. (steel) The macro lens of modern smartphone is rather useful for this : More closely investigating a rather shiny cable where is runs with considerable tension under the pulley, one broken strand. Can be felt with finger. Replaced. One might think 1 of of 49 (63?) strands is no big deal, but reading AC43, and closer inspection reveals the flattening wear of the cable (making for shiny appearance) is the cable strands being worn down and thinned under the pulley pressure... and eventually one lets go. Given that a lot of them are simultaneously worn down and thinned, a whole lot might let go shortly.... You could probably fly on this for another year (or 5) with before every flight inspection , but given that cables are in stock locally, it should be replaced. Document AC43 provides guidance on this, as usual . (replace it) . Lots of airplane maintenance stuff is annoying and painful, but ultimately these annoying things, will save your arse.
  3. there are some differences and compatibilities between certain types of 'suppressor leads"
  4. HONDA part number 30500-Z1C-023 Go onto jab-camit groups.io forum for more information here https://jabcamit.groups.io/g/main/search?p=recentpostdate/sticky,,R ignition coil failure,20,2,0,105990390
  5. yeah but some of these strips you want something different.... like flying in across a deep ravine, I think that's a engine-idle glide approach , so you will make it and not fly into the side of the mountain if you have a failure.
  6. There is a thing I think needs more focus on in classrooms and teaching. I call ' dead man's height " where at about 10 feet you can stall and break to the main gear. We've all been very close to it at some point in our flying during landing and training . either --------you flared too early and you're still 10-15 feet above the ground but now speed / energy has decayed and you're only just at flying speed above the stall, OR - you bounced... this is a problem : i) you cant do another flare,- the flare is an exchange of energy and there's no excess energy (speed) available to do this. ii) and the speed will decay (while you are 10-15 feet in the air) to below stall before you come down to the ground . wing drop or sudden whole aircraft drop. iii) and you cant point the nose toward the ground to get it down because you'll likely smack the nose on the ground -- as a nose down will kill any lift you have with sudden reducing the AoA and drop u like a stone on the nose. Human reaction time isnt good enough to point nose at the ground from 10 feet away and then immediately bring it into some precision save. If you are *lucky*, the aircraft will drop close enough the ground into ground effect and buy our aircraft a few more knots before stall. Likely is you'll pancake on the mains and the nose. This save is more arse than class. If you bounced because you had way too much airspeed on the first touchdown , and IF you know the airplane well and have experience, there's probably just enough for a 2nd flare/landing. It will still be a bit ugly and heavy. You might think you can add a little throttle but this can leave you not falling but still decaying airspeed because the aircraft is in a high drag configuration (high AoA, flaps) So, the decision has to be made for a committed go around a few knots above the critical speed. Down near the stall, aircraft control is usually sluggish and woeful, so dont wait till its like that ! This brings me back to non go-around strips. There has to be committment. And with that there needs to be precision with the approach (stabilised) , caution and preparedness and some rehearsed in your head actions.
  7. the BMS MAY do a number of things 1) first and foremost- ensures cells stay balanced. usually this is done by shunting current around a cell if it is higher than a max voltage. IE it stops a high cell rising further. most have passive balancing- think of a 3.6V zener diode (or approx that) across each cell. during charging, if the cell tries to rise above the zener voltage of 3.6V, the zener tries to short the current, preventing current flowing through the cell (preventing more charge). there is some active balancing systems where there will be some controller that attempts to equalize the batteries by pushing charge around. I'd expect most vehicle batteries (EV) to do this. 2) low voltage disconnect - I wouldnt want this in an aircraft.... often they wont reconnect without some specific charge type. 3) over voltage disconnect - not so common- disconnecting the battery from the terminals if the voltage is getting too high (charge source unsuitable) . LIFEPPO4 batteries are in general not compatible with common charge systems.. this is because their internal resistance is very low, and the batteries being charged looks like a short circuit- chargers need to be current limited. Voltage wise, they're quite compatible with lead acid ... as long as a lead acid charger (usually used for remote power systems) doesnt have an equalise mode enabled where it intentionally gases all the cells (high voltage) to get them all the same.
  8. depends how RF noisy it ends up being....
  9. the problem with those batteries is some of them can disconnect themselves ... that is bad for electronics both lack of power supply, and consequent high voltages and nasties that will occur with the perm mag alternator driving no battery Rotax have shown poor engineering judgement (lack of capability, understand, experience and knowhow)
  10. I do not think so. . It is really important the GPS antenna gets mounted with an unobstructed view of the whole sky
  11. what's up and what is down ???. I presume that's your ADSB transmit antenna, underneath the empanage.
  12. Pretty good result really .....can be happy about that. Lived to tell the tale. But why did it stop? Being on top of the maintenance of my Archer I feel it's only going to ever stop if the the pilot messed up (fuel selection, fuel monitoring ) , or something got missed in maintenance. Lycomings and Pipers dont just stop randomly. Everything that breaks or wears out is absolutely known. glen
  13. Red said : "You simply need to connect any GPS Source that has NMEA out capability to the XPDR, its one wire and a ground" NO ! You must use a TSO certified GPS. You are not permitted to use "Any GPS" Burnie's post is correct"https://www.recreationalflying.com/forums/topic/39965-transponder-adsb/?do=findComment&comment=568941&_rid=11148" AND - the location of the GPS antenna must fall inside zones spelt out in on of the advisory circulars. basically between the cabin and the tail fin.
  14. Nev, I see lots of GA people AMS, LAMEs running engines without cowls well above runup speed and I voice my opinion... People just dont realise that the air must go between the fins, and will ONLY do so if there is no other choice. Blowing air across the tips of the fins (open cowls) is almost useless compared to the actual airflow requirement...
  15. Hi Mike, nice writeup. Carbon forged ? what is carbon forged ? Be careful of ground running. You need more than air directed down at the fins, you need air forced through them. Given ANY opportunity to go around the fins, air will. (WHich is why Jabiru head cooling is so bollocks) . Needs full baffles. be sure to have CHT probes hooked up before running... and keep ur eyes on them !
  16. I'm thinking of running for the board. The RAAUS office is 2km from the factory.... it's this time of year isnt it, might be too late.
  17. north canberra (Kaleen) to cowra 1.9 hours. 180km door to door, 2 sets of traffic lights.... I have accomodation up there and a workshop, so that makes life easier. I always leave at 0600 each way. roos are not too bad right now with plenty of non roadside food to eat.
  18. maybe, I cant remember , it was a while back. apart from difficulties users had with the airport operator, the lack of ownship and investment- IE at cowra and temora, the rates from the new hangars / land sales offset maintenance costs, leading to a well maintained facilities, and less of a transient nature. for cowra - There's also many businesses that run out of it- maintenance facilities, ag facilities and a big flying school. There are a few other issues not easily sorted- The weather is in general not all that aviation friendly - hot and high in the summer, and eternal fogs in the winter, and substantial crosswinds on the main. The place is a mess also. no investment by anybody. littel ground upkeep. This is all pretty much seen as the symptoms of the operator and the relationship to the users. If the council had maintained ownership, they could have done a subdivision. I think it is unlikely people would buy land in a subdivision from the current operator. However, despite the problems, I think it would be an option for canberra/ regional people. The cross grass runway could be improved and extended another 300m, otherwise(very) light aircraft face regular uncomfortable crosswinds. A power line could be relocated If I was flying out of there regularly, (I use my plane to go places and I need to be there when I say I will) an instrument rating would be a must.
  19. ideally, in the perfect world, the sense wire would also have a fuse (say 1 or 2 amps) to the battery IE anything directly connected to the battery (and not able to be disconnected) must be fused at the wire rating.
  20. I have seen a document produced for the council (on request) by a development consultant - helping then understand why cowra and temora had been development successes for those councils, and why GLB had been pretty much the worse example in the state. doco is about 4 years old ....
  21. heard from anyone actually at Goulburn airport , or associated with the council ? glen
  22. Hi Kevin I dont know about a new new Jab regulator, just incantations of the Kubota, or $40 ebay copies ? . 14.7 is too high. Do you have the sense wire going to the battery directly ? Those crimps are not much good above 10 amps. Unsurprising you have a bad one. I would suggest a 25A amp blade fuse in series with the stator. Suggest on both wires (two fuses) BTW am keeping my jab. I will have a new jab regulator for sale in a couple of months... just moving my factory, it will able to be purchased from my web shop.... - can deal with flat lithium batteries (with current limit) - can provide charge from 600 rpm up - won't blow up and put the battery across the alternator stator cooking the stator.... - crimp ring terminal screw down connections
  23. however some puzzles : What I also saw was higher than usual, for a given fuel flow , was slightly high (20F) EGT (single EGT readout) , (leaned to peak EGT at 65% power) ....despite the negative OATs. - As usual , no difference on AVGAS or 98ULP. ...have a single EGT readout. My 1st guess is that in these conditions, one or more cylinders were going too lean (before engine stumble) later IE , during the process of leaning for peak EGT / engine stumble, the monitored cylinder EGT got leaner (and hotter) than ever before when perhaps other cylinders were later getting leaner than usual, hence reading a overall leaner mixture onm the monitored EGT before stumble. Usually, the monitored EGT cylinder when it just goes a touch beyond peak EGT, the engine stumbles. Useful reason to have EGTs on all cylinders. Useful for troubleshooting/depuzzling the puzzle.
  24. anyone finding that with all this high pressure and low temperatures, they are needing more right pedal on TO climb that they usually do ? I am ! Cowra was 1000' below sea level yesterday mid morning..... (instead of 1000' above)
  25. Both Goulburn and crookwell have challenging weather. I was considering moving to goulburn but I decided the weather was too foggy too often (compared to cowra where fogs are the exception rather than the rule) . In summer at Crookwell, with an easterly, you better have done your numbers if the grass is between mowing.. Goulburn at best $3mil. the strip and need need work.
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