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RFguy

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  1. RFguy
    mmmm Is this an external intercom to the radios, or two radios wired up with a switch, or paralleled outputs or inputs ???? Please provide a mud map ! thanks glen.
  2. RFguy
    or a six engined flying boat made out of wood ?
  3. RFguy

    J170D Production

    RFguy replied to CAV0K's topic in Jabiru

    Jabiru will need to get costs in check I think if they want to remain competitive. The J170 as a flying school machine now pricing provides for many options from other mfrs in that price range. you might as well buy a used foxbat or brumby for training. There are alot of J160/J170s in the marketplace, its possible that the market is saturated. Jabiru airframes tend to last forever (even if pranged and repaired ) so maybe there are simply enough J170s in flying schools and flyingn schools are peaked. The J230 is the only genuine, fast-ish , well CG behaved load carrier in RAaus class... hence its attractiveness. Now if they'd offer a 912 / 914 power plant, that would be a killer. and sell twice as many.
  4. RFguy
    which way you go sort of boxed by whether you will go barb hose clamped or AN series. AN is nice but given the low pressure ( < 10 psi) pos and neg, I beleive the barb fittings are entirely adaquate. I would NOT skimp on the sizes of the hoses on the suction side (engine to cooler, cooler to can, and ensure they cannot suck in / collapse. Clearly (industry experience) the native rotax fitting sizes are acceptable for short runs of tube. The cooler likely dominates the suction tension. If in a cool climate Suggest an oil thermostat like a Denali, available with different fittings, mine has 1/2 NPT in the body, there are other sizes
  5. RFguy
    ahhhh. right.... I cant see how a machine test can emulate flying conditions, given the way the airspeed is 'collected' , and all the variabilities. Flying up and down a course is not too demanding....
  6. RFguy
    How did they generate calibrated airspeed- some sort of transducer/ jig applied to the tubes or was inferred by flying ? I dont think this is necessary - since the aircraft will have its own CAS-IAS chart for its airspeed readout, and this is an independent system. That is a LAME/L2 job every two years in RAAUS I thought . As for checking if the GPS in the transponder was reading correctly- that's a load of crap IMO, use of a TSO 199 GPS means it will not readout errors without displaying an error flag- IE the GPS system in those is self aware of errors and checking. https://www.icao.int/APAC/Meetings/2015 ADSBSITF14/SP08b_FAA TABS briefing.pdf TSO-C199 Requirements • Cannot transmit false or misleading information • SDA=1 (1x10-3 or better) • NACp=9 (30 meters or better) • NACv=1 (10 m/s or better) • NIC=6 (0.5 NM or better) • SIL=1 (1x10-3 or better) • Detect Step errors greater than 700 meters • Capable of using SBAS integrity
  7. RFguy
    If you need space and payload..... and speed... 700kg J230D. hard to beat in RAaus. 80kg in the back no issue.... 620kg with full fuel (140 ltrs + 2 pax) ... Centre of Lift of wing is over the "BAGS 1" so CG is generally always in range and hard to screw up . and you have the huge back door (that leaks ha ha) and flies better with weight behind you, also. Take a look at other airplanes CG envelopes in various configurations.
  8. RFguy
    Goolagong is not "God's county". Kingaroy is "God's country".
  9. RFguy
    I'd stay with those AN fittings on the ends of the M22 from memory Setrab interface. efisolutions in QLD have a good range, and you can find other misc items from Sparesbox and other car performance shops. Quite common. SOunds like skippy has all push on. Pressure is low (and negative on the oil cooler side ! ) in the rotax system, suits push on.... Marty what connectors are on your oil can ? I found that interface to the AN oil cooler a bit of a pain but findable (M18 from memory IMBW) -glen.
  10. RFguy
    Wednesday, Thursday : Thruster88 and I flew my new Archer down from Charters Towers to Cowra, made it a two day event. Could be done in one but the LONG day would remove the fun. We have never seen any of central queensland, so this was a good chance to look around. Locals at airports very friendly. Overnighted at Cunnamulla. Nice full river running through it. Plenty of greenery around. 'soaring' techniques I learned during training with Rob Glenn in a hot summer years ago now - to see a thermal present by increased VSI , then pull the nose up slow and try and stay it in as long as possible. Required technique when trying to climb from 7500 to 9500 to take a look in the Archer. Turns a rather anemic 400 fpm into 800 fpm. I'll take that- it is the only thing is life truly free. and almost as good the big Jab LOL. I love NDBs. Such a great facility. Much more engaging than GNSS. and Thruster88 gets to practice his morse code.
  11. RFguy
    test the ASI ? sounds like he was trying to bill extra hours. unless your aircraft was (over) due for testing as normally required is it every 2 years for a RAaus ? and no need to test the GPS, is is guaranteed to be accurate by its certification. (again might be a test). There is a CASA instrument that stipulates what needs to be tested after what changes are made, I will have a look at it, others might know.
  12. RFguy
    What was recovery ? move all the drinks trolleys to the front of the aircraft ?
  13. RFguy
    Putting aside CG location, recovery is usually about two things. Elevator authority that situation, throttle position. Certain combinations will be unrecoverable. But I think you know that , and that's not quite the question you are after. Recovery may not be possible if the CG is aft of the COL and the elevator gets locked into an aerodynamic situation where it (continues) to have no authority (IE no ability to pitch the aircraft so to reduce the AoA of the main wing below stall angle) . Take a look at some of the aircraft with specified NORMAL, UTILITY and AEROBATIC category weights and CG limits. Aero cat takes into account the higher likelihood of getting the aircraft into a more difficult to recover situation/configuration. So, its possible but unlikely to get NORMAL aircraft into difficult (recovery) situations, but highly likely with AEROBATIC. That and limits of airframe G force limits (weight). Nev (since you flew them) I was reading about 727s years ago in one of 'Jobs books where the recovery of the T tail in some attitudes was problematic, and this was new to many....
  14. RFguy
    The less the tail has to do the better for efficiency. Bruce do you recall, for those gliders when set at the "design aft-limit" , in response to a impulse pitch input (up or down step), in terms of dynamic pitch stability, were they over damped (return very slowly to original attitude) or underdamped (borderline unstable probably aft CG for that airspeed/loading) IE entered an oscillatory condition like a car spring without a damper ) or somewhere in between ?
  15. RFguy
    It's interesting to examine NORMAL or UTILITY category aft (and fore) CG limits if provided. Nev you are right an inch on a sailplane is (generally) alot less (% MAC) than an inch on a short empanage powered fixedwing. Bruce, is the fastest way down in a Libelle to induce a nose down spin ?
  16. RFguy
    I dont think it stalled at all, looks like a perfect flare and land on the ocean, with enough energy / airspeed to get a GOOD flare (lots of tail authority)
  17. RFguy
    Maybe, except there are many variations on crimp connectors- many crimp lugs require to get pinned from underneath- one side is a hemisphere (sortof) and the other side a square pin push Depends if you are trying to get a swaged joint, etc - many variations. Before substituting a makeshift die, try and get a look at the real tool.
  18. RFguy
    do that. The twin filter Mr Funnel I have will keep up with a 20 litre jerry being poured in at max rate... Ideally, you need to fashion a collar for it to sit on- stops it falling over slightly, I use a I think 50mm long , 6" diameter bit of poly pipe with a antyi-scratch bead of edging on the bottom. . the collar becomes necessary as the things starts to slosh around when the pour rate is high
  19. RFguy
    Low speeds is bad and hard on the gearbox and everything, Rotax specifically recommend minimum time at low RPM. Probably depends of you have fuel that is likely to varnish up, or evap (ethanol etc) in the bowls, or not, to whether you want to starve the bowls dry on shutdown me thinks. Mr Funnel comment- buy the one with dual filters- otherwise it will not keep up with a 20 litre jerry pour.
  20. RFguy
    But not too many of them (rotax) stop. The failures of the ignition modules though was a real FU by Rotax and shows where they are good, and where they are not. Stacking two ignition modules hard on top of eachother in an area of high temperature was just asking for trouble. A 10mm gap between them would have ensured cooling. In my opinion, electronics is an area NOT to trust Rotax due to their demonstrated incompetance. However, they have demonstrated competance (to me) with the hard to get right stuff like pistons, heads, cooling, gearbox. The inlet manifold is a bit of a compromise (mixture variance front and rear at low gas velocities ) but its bearable. The dual carb is fiddly but acceptable.
  21. RFguy
    cant compare unless airspeed /efficiency is in the picture. I went four blade for rotax because of superior takeoff performance- more blades, less blade loading per blade and not as far into 'stall' if you like , IE AoA per blade lower , ---at low airspeeds much less than the screw speed. Exact performance will depend a bit at what drag you end up with and IE what RPM your end up with. Little / no penalty for 4 versus 2 blades with the Eprop at cruise speed. That's the advantage I like. AND Eprop will get you all this data...
  22. RFguy
    CRIMP, for sure. soldering creates a brittle, heat treated joint. Suggest as high strand count as you can get. Now, as for wire : and, may I quote AC43 : There is no need to speculate. AC43.13-1B , https://www.faa.gov/documentlibrary/media/advisory_circular/ac_43.13-1b_w-chg1.pdf CHAPTER 11 - AIRCRAFT ELECTRICAL SYSTEMS Section 6 : Aircraft Electrical Wire Selection. Section 14 : Terminal Repairs. 11-174 General 11-178 Crimp on Terminal Lugs I strongly suggest users modify and maintain their LSA airplane electrics to AC43.13. There is about 20 good pages to read between Section 6 and Section 17. That been said, I'd suggest a high strand count cable with insulation good for fire temps, and appropriate crimp lugs for that cable, and a suitable crimp tool , or fashioned die in a vice to generate the impression.
  23. RFguy
    Well the #6 telltale will likely be recession., that's the hottest spot.... Do check that the rockers slide left right at TDC. exactly how much spare clearance you have depends on WHICH lengthof push rod Jabiru gave you. they vary.... most of the original Gen3 were too long and then went down a couple of mm ! (and didnt tell anyone and the manual has errors) eventually, you'll need to remove the heads , milled down say 0.9mm from the non recessed area so you get a nice flat surface again, and then drop in a 0.9mm shim. like below :
  24. RFguy
    I mean WHICH screws out of the 6 moved ? I cant beleive that is Jabiru's advice as it is bollocks in IMO if that is so. Problem is dynamic version static friction influencing torque. Hence the reason to back them off to they are moving when you are measuring torque. Otherwise resultant tension could be out by perhaps 2:1... as you are overcoming static friction, corrosion etc etc lots of errors.
  25. RFguy
    if you are employed as a contractor, that's the big bucks
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