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RFguy

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  1. RFguy
    Let's see here. specs. empty 985lbs(447kg) with Titan340 . mmmm I'd want a 140 hp engine for that plane with those numbers and role. So a 915 is an excellent choice I think, Mark. But 914 too small. 916 is unnecessary. The weight (447kg empty ) would be only 400 kg empty with a rotax, so even 130hp would be good. Mike, according to the datasheet, the conty in MOGAS compatible format (you'd surely want that) is 8:1 and 174 hp. I am sure any issues with the CG / aft load etc could be solved with the 915 by moving sh1t around. ....-glen.
  2. RFguy
    yeah I was in suboptimal shoes also (Volleys) . my feet killed at the end of each 14 hour day on my feet even with silicone insoles.
  3. RFguy
    I'd reckon rotax would dot their i z and cross their t z, I'd have no concern with buying a 916 if I could spend that sort of money. (But then I'd buy an IO-360 instead of a 916) Remember- Maximum continuous power is 137hp for a 916. 160hp is takeoff power, and short term climb power. 200hp IO360 can do 200 hp all day if you keep the CHTs down...... and does not have any complex electronics nor water At altitude, the Lycoming will still make good. I reckon usual story for turbo if you consistently operate hot and high, then the turbo engine is for you (or buy a slightly larger Lycoming an IO-390 ) 8.5:1 IO360 can run MOGAS. not sure about 8.7:1 version (check) . dont think 8.9:1 '390 can. I like having the extra HP in my bird so that I can still put out good speed/power even when leaned extreme (65-70%) . Gearbox is nice on the rotax though- low speed prop- more efficient slightly, AND not same issue if you have a prop strike.... Might have to think about weight though.... not having the boat anchor up front will change things. Wonder if the 916 will have a oil thermostat as standard- they SHOULD have IMO. (for fast warmup and stabilized, correct oil temp)
  4. RFguy
    Putting aside spark plugs connections (I dont think that's the problem) ---I'd ensure all the plug in connectors in ALL the harnesses and plug in sensors are well seated and fixed down so they cannot free vibrate. You might cycle the harness and sensor connectors and inspect terminals under light and magnification . Of course, I am guessing, but this would be my immediate checks
  5. RFguy
    maybe some issue with a combination of higher vibration (low RPM) and less than perfect crimped connectors. someone must know at factory.
  6. RFguy
    Howdy I've heard of this from an aircraft on the sunshine coast. cant remember which.. I would be sure rotax have a diagnostic log in their box. This will contain the info.... Many engine shops, not sure about Berts, are generally low tech affairs and shy away from this data.... Talk to the factory . is this at low idle or moderate power ? gather in a flare so it is occurring at idle stop ? - glen
  7. RFguy
    Mark, BTW according to Mr Factory Rotax (at the show) , while 912, 914, 915 are similar beasts, 916 is new crankcase, new gearbox, new turbo. .....also, old turbo in 914 is no longer available. Has your S21 got the big bore 912ULS in it at 10.5:1 ?
  8. RFguy
    How about gearbox compatibility ?
  9. RFguy
    For those wanting a different wing, a wing change would require a lot of engineering and test. I think the existing wing is fine. If you want a shorter landing airplane, just get the drag up. there is a way to do this. (apart from ensuring your idle speed is lowest possible/safe) Jabiru actually reduced the flap max deflection in its aircraft 2007 ish because it was found that it didnt provide anymore lift, just more drag, and that it wouldnt climb in a go around terribly well at max flap.... I think that extra drag is definitely useful to reduce landing distances, and will modify my aircraft I think (move the flap motor stops ) . Sure it wont climb easily in a go around at the max flap , but neither will my part91 certified aircraft. I know another owner that used the extra available unused motor travel to reflex the flaps, for slightly higher cruise speed.... but it turns out the most drag at cruise is not the wing but the nose and the gaps and the mains. -glen
  10. RFguy
    Well , deadly silence from Jabiru upon the question this morning amongst other correspondance. Must be true. Maybe I will keep my J230 and finish the rotax conversion. (need to do a customized exhaust system, or just use straight pipes out the side) . Maybe inject some avgas into the outlet pipes for effect instead of the strobes.
  11. RFguy
    Today, in email conversation with Jabiru regarding current engine delivery (about 9 months for a Gen 4 3300 is the answer) I have asked the question about the company sale.... No response, so far. We'll see.
  12. RFguy
    The air is different in Europe, the air they breath and fly in is denser by being subsidised as extra 0.3kg per cubic meter by taxpayers , leading to a lack of world competetiveness, and aircraft that can only meet their specifications in european air.
  13. RFguy
    Hi Mark I see some aircraft have BRS fitted behind the instrument panel.... Is the S21 Conty mount just for a generic continental, or is there something specific about a Titan 340cu" ?
  14. RFguy
    I might add on the Va thing, while its accepted Va can calculated by taking the clean stall speed multiplied by the squareroot of the load factor, In the example I used above of the ATEC, that was the designed load factor (3.8g normal category ). HOWEVER If the aircraft did not break say until 8g, then the designer might use that value in the calculation of Va (but the FAA might not like it) . In the book , Faeta NG is given at 600kg, Vs1 of 40 kts. and 4G limit. which implies a Va of sqrt(4) * 40 = 80 kts. If the aircraft didnt actually fail until say, 8G, the mfr might write down 113 kts. That might be OK for LSA, but for a Part 91 aircraft , the FAA wouldnt accept that (is my reading).
  15. RFguy
    I imagine they'll move prop maybe forward, battery forward , oil tank fwd etc etc all the usual. The TAS is good, Mark. 10,000'. Well like I always say, if you fly low you are leaving TAS on the table. (said from a cross country flyer's perspective). Mike when are you back in Australia ? Stuart and I will make a trip to see you. cheers,
  16. RFguy
    yeah 915 is better because there is a turbocharger there.... but hard to go past an O320, surely ??? (or was it a 235 you were looking at ? ) what about CG Mark- do they need to move the propellor location forward to get the same CG range ? (IE without that paperweight Lyco-conty on the front) ? or is the paperweight actually too heavy (or suboptimal) for it ?
  17. RFguy
    I expect they would sell a ton of J230 airframes with a 3 blade 912ULS in them. and 914/915 as a upmarket option. although these days, there are many composite competitors snapping at their heels. It's not a complete shoe-in. assuming same thrustline and prop location (as I had), cowling needs to be bulged a bit on front lower to accomodate the exhaust headers from the front two cylinders.. not too much work really.
  18. RFguy
    I suspect a few high profile failures at this stage of market penetration could be curtains for UL, unfortunately. Yeah, Jab engines with Jab factory props (whether wood or composite) give a statistically insignificant number of reported problems. Ever seen the big bearing at the front of a lycoming ? a few inches long ! There is a reason for this... Jab also put alignment-fixing dowels onto the crankshaft-prop flange sometime around 2013, also. So something must have been amiss that we didnt hear much about.
  19. RFguy
    I'd absolutely suggest using a Lyco or a Conty. The UL while similar to the Jab, it doesn't have much case time compared to the Jab which hasnt changed in the bottom end for a long time..... Jabs bottom ends dont give any problem unless their thru bolts break or are not correctly fastened (assuming initial assembly was good) . I'd suggest for others a low cost on-condition post TBO Lyco is still a better bet, if the aircraft can deal with the extra weight, which can be reduced with electronic magnetos, getting rid of the vaccum pump, lightened exhaust system, lightened rocker covers etc etc. I would be HIGHLY surprised if the Airmaster was suitable for the UL, since the moment of inertia is miles beyond the listed limit for the Jab engines, and the bearing setup is similar.
  20. RFguy
    If I assume it is a normal category aircraft (3.8g) at MTOW, and the clean stall is 39 kts at 585kg, then the ATEC faeta ..... Va is 76 knots. (@MTOW J230D is ~92 kts) So you better slow down if you don't want to overstress the airframe. Saying that I would still like to own one of these aircraft for high speed, low cost commuting. anyway this forum is about the JABIRU SALE.
  21. RFguy
    yeah adjustable seats are done by swapping out various under your butt + behind your back foam/cushion combos......
  22. RFguy
    SKippy, Jabirus are fine. I think I have to slap you with those remarks. Push pull controls need very little maintenance. The whole floor , covers, and rear has to be pulled up in my PIper to inspect the myriad of cables, wires, pulleys, wheels turnbuckles etc etc Stall speed is fine. 40 knots is fine. ANything slower than that and unless your technique is good and you have a giant rudderm, crosswinds will be MUCH more of an issue for a pilot of average ability. Slow is not always good. Wing is fast enough and is very efficient. You will not go much faster than they do for a given stall speed and airframe weight . The Jabiru is about as good as it gets. sure could have a tidy up on gap seals etc, but it isnt much . Lower stall speed is an issue if you want to go fast because Va is proportional to stall speed. This means if it is ever bumpy, you will have to fly MUCH slower otherwise the aircraft will be overstressed. Sure yoru Faeta will cruise at 125 k, but it has to slow down to like 70 k if it gets bumpy !
  23. RFguy
    yep, you can buy a 912ULS core for 28k. all accessories if you buy rotax (expensive) ones brings it to mid 30s, I think. But you get 2000 hours TBO without touching it , almost. Still , I don't hear too many gen4s blowing up these days, either. Hopefully, New Jabiru will offer Rotax powerplant for their aircraft. They'd sell alot of J230 hulls. They might outdo C172s.
  24. RFguy
    update. on the HDX performing a CDI (course deviation indicator) function . using an ARINC429 interface (a type of aviation instrument bus) between a WASS GPS IFR approved navigator (like 430, 530, 175 , 375 etc) the HDX skyview is FAA approved for IFR for using the CDI function in the Skyview. That is, no discrete CDI required in that case. (according to the manufacturer in writing) .
  25. RFguy
    well, an RPL and class 2 BASIC medical is a pretty easy conversion. This leaves the issue for aircraft that can fly at 700kg (J230) but are placarded to 600kg. and.. what are the pathways for uprating an existing factory LSA. Can it be done by re writing the placard and turning it into a 24-experimental via an MARAP ? (I wouldnt recommend at J230 > 700kg because I think the mains are not up to the increased landing speed energy having seen two broken now on others landing downwind)
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