Jump to content

RFguy

Members
 View Profile  See their activity

  • Posts

    3,472

  • Joined

  • Last visited

  • Days Won

    47

 Content Type 

Everything posted by RFguy

  1. RFguy
    IMO you want to keep the exit coolant temp at least 10% below the boiling point of the coolant at the operating pressure. Bubbling, gassing will upset the flow and lead to coolant being ejected into the expansion bottle (bad ish) . Vapour spots 'hot spots' have a higher potential heat removal capability than liquid water conduction regions, depending on flow.. It's hard to know how big the hotspots would be because they would vary with flow and viscosity which beleive it or not, varies quite a bit for common coolants. Remember , Ally Alloy has a fairly high thermal conductivity so hot spots are unlikely because they'll just conduct the heat to the cooler spot. **Plenty up for chance and speculation without accurate physical modelling !** so just keep the coolant 10-15 deg below the boiling pt I'd keep the temps below boiling pt for an atmospheric pressure of 50/50. IE below 106C. Anyway, I dont think you have coolant temp issues, you need to get the oil temp down. 80-90 deg C hottest.
  2. RFguy
    Sounds like you need to change the balance of oil cooler airflow and coolant airflow. Skip what size ID hoses did you end up running between tank and oil cooler and engine ? I'd keep the coolant below 110C, despite being an anti boil mix. rates of corrosion increase at higher temperatures. If you can measure coolant rise across the radiator or across the engine, that will give you lots of extra info.
  3. RFguy
    My Kluger.. on my OBD in hot summer, never seen the oil go higher than 90 deg C. and i have never seen my Lycoming above 85C, sits a round 80-82C But, yeah I agree 90C-110C is probably fine, my point is that you are leaving some cooling on the table - that oil cooling is the low hanging fruit to cool stuff in your engine.
  4. RFguy
    that's all crap about oil having to be 100deg C. water doesnt suddenly start vapourizing at 100C. rapid evap is well and truly underway at 80 deg C. It does take a little more to evap water out of suspension/solution but not that much. Atmo pressure also falls with altitude, makes evap water easier...
  5. RFguy
    Skip, in my opinion, that oil is still too hot. by about 10 deg C.... but, getting there. water temps seems OK, something is wrong with your oil cooling... or biased too much one way., IMO.
  6. RFguy
    this is the easiest https://www.flightstore.com.au/aviation-headsets/plugs-jacks or, buy from clearprop, ozpilot, or mobileone .. I get mine from Mouser but you need to know all the cryptic Switchcraft numbers.
  7. RFguy
    BTW yesterday I installed a FUNKE ZATR833S in a friend's aircraft. It is superb ! easy to setup, everything is controllable, adjustable from the panel, wiring it is highly adaptable, real nice kit . good ext audio input options, adjustable sidetone level s indpenendent of mic gains etc dont forget to set it to 25k channel spacing once installed. sounds good on air, also. https://www.ozpilot.com.au/product/funke-zatr833s-vhf-transceiver/?utm_source=Google Shopping&utm_medium=cpc&utm_campaign=Ozpilot Products&gclid=CjwKCAiA1fqrBhA1EiwAMU5m_0bZoX14nmGoZrjP0sMxGlTzcim12-uPIdLPcLhAhz692YI7X07znhoCq1MQAvD_BwE
  8. RFguy
    I have already made my conclusion. And it is harsh ! Pilot became unconscious. Passengers were not sufficiently briefed on activating the CAPS system (shutdown engine, activate CAPS). Should have been with so many souls on board. It is a terrible ending to a what should have been survivable situation. Pilot only accumulated 800 hours in 38 years which for me is a question mark. For whatever reason he failed to provide duty of care to that family through his own errors.
  9. RFguy
    This concept is covered regularly in science fiction.
  10. RFguy
    mmm a couple of things 1) on points of fault / incident reporting. seems the biggest reason for not getting fault/ error reporting is people thinking someone will get in trouble or it will adversely affect them for whatever reason. Need to figure out a way to change that mindset to the right sort of no blame/ no fault. Of course- no blame no fault cant be unbounded - so that's the sticky bit. I've heard of two Jabiru oil filters splitting, (could be the high pulsing PRV or could be mfr defect or steel too light or ????? ----but they have not heard of this- this is an example of owner/operator reporting defficiencies. 2) With regards to the meat of the discussion, my concerns with a certain manufacturer's behaviour - there has been an ownership change , and broadly issues I have raised as a company culture problem will get addressed, but it wont be overnight. -glen
  11. RFguy
    back on topic. skippy please dont bring yout sonex and soneri talk into the Van's forum. We're tired of it. Van's will be fine, YES VERY TRUE - they make a NICHE and HIGHLY SOUGHT AFTER product- which is a good commercial recipe to be able to put your prices up (as necessary) . I doubt a 30% extra cost of kit would change anyone's buying habits...
  12. RFguy
    SKippy, I do not beleive you will acheive those numbers. given that the sonex with the 3300 jab will only make about 155 kn T at 6k feet at 7 gph) . (source : sourcebuilders website ) You migth do it for the same fuel consumption though, make the rotax work harder . fixed prop of course.
  13. RFguy
    yep, Lycoming can lean aggressively. also try Litres/nm that's easier to calculate. the piper will do about 244mL/nm at 90 kts at sea level, or about 260mL/nm at 120 kts at 10k feet fully loaded J230 will do about 230mL/nm at sea level, 115k. 212mL/nm at 6kfeet ~ 125k... The J160 15/100 = 150mL/nm Your RV at 25 lph at 140 tas = IE 178mL/nm..... (really ?????) gather at 12k feet ?
  14. RFguy
    Had a useful and constructive meeting with RAaus today.
  15. RFguy
    There's also a 100% cover kit from Punkinhead at Yarrawonga. It's comprehensive. I have one for when I've had to occassionaly live outside for a few weeks. A quote I heard recently : You are paying for the cost of a hanger whether you are in a hangar or not. IE extra maintenance if you are not. But a full cover can go a long way.
  16. RFguy
    Just was on the phone to a litigator friend of mine. next steps 1) thoroughly understand what the relationship is between RAAus and CASA, and how it works, understand the legislation first. and then choose a small number of items that , where in my opinion RAAUS are not fulling their obligations under the act. and / or 2) and consider making it a civil complaint against the aviation company I am complaining about (that , IMO, RAAus are turning a blind eye to, or are simply not sufficiently competent to do meet the requirements under the act.) . Incompetence leads to negligence, however whether they knew it was substandard or did not know, that's the messy bit. A bit can be drawn from the previous action. I'll take a look at exactly how and why CASA got involved. It's generally accepted that CASA's previous involvement was rather clumsy .
  17. RFguy
    The RAAUS staff and board just does not take safety seriously, it's all a big front.
  18. RFguy
    Yes SKippy, that is right- must go with some solutions, otherwise I will just be a whiner. ahh well they've blown me off for tomorrow. disappointing. I wrote to them detailing my concerns about the number of Jabiru fires a month ago, got NO reply, zero..... So I wrote to them again, they set a meeting date, which I arranged to be in town for, and they've blown me off and 'will listen to my concerns by telephone'. Not good enough. Time to go to talk to CASA and bust their arses.
  19. RFguy
    I have a face to face meeting at RAaus tomorrow. anyone want any questions asked ? PM me directly.
  20. RFguy
    if you buy something NEW in a box, then you might cop 5% duty + 10% GST on entry so dissing stuff out of all the packaging is one way to reduce that. You might have bought it used, right ? otherwsie for a fleamarket, it might cost $1 right ?
  21. RFguy
    "Yes, the current enigines produced by these Japanese manufacturers are not ideal for aviation use (but they are close)." why not ?
  22. RFguy
    KG what are your total estimated servicing costs over 300,000 km ? just wondering
  23. RFguy
    and EVs right now, with their pricey tags, owner's expect they're not bottom row, are also at a luxury 'ghia' etc Not the bottom line vehicle like a very cut down Hyundai Excel , there's no such thing as a Hyundai Excel rock bottom car that's an EV... On the aircraft. yeah. the 180hp Piper is good for going to see clients (sometimes full to the brim with gear), family, or crossing endless tiger country or water however for going and seeing friends by myself regularly say 450nm, something like a old J160 costing 30k, wouldnt bother insuring it , and costing about 160mL/nm compared to 260 ml/h (best)... Which is why I am selling the J230. (halfway between the two requirements)
  24. RFguy
    Look. 1) electric cars are nice, but as highway cruisers they are marginal ROI . 2) For city stop start folk that can use regenerative braking effectively, they are fantastic. and they are price comparible with ICE cars as they havea small battery. but if we take the highway cruiser : The 50k electric car (with a 300km battery) once youve done 300,000km in it is going to have cost you $66,000 (electricity costs from the mains at night) . plus perhaps $500/year service (15 years) = 73.5k The 30,000 hybrid car at 4.5l/100km is goign to be $27,000 in fuel at 300,000km, so $57,000 (plus alot more in servicing, say $1200/year x 15 = 18k = 30+27+18 = 75k But to be apples with apples for highway cruising, you really do need at least 450km range or a 65 ish kwh battery .. really you do.... so you really need the 65k electric car. so you electric car is another 10 grand. this is all assuming you are not paying any sort of CO2 polluting tax If you have a massive solar array at home say 15kW your electricity costs are goign to be much lower, eventually) payback time on investment not to be forgotten ! so....
  25. RFguy
    Taking into account the cost of filling a battery at night from the mains.... and what it costs to run a hybrid Battery costs at the moment essentially means that if you buy an 330km range electric, compared to a hybrid, you are pre paying your first 12,500 litres of fuel, roughly prepaying your first 265,000 km in a hybrid ( 15 years ?) . given it costs about $5.50 per 100km for the electric (home charge) , over the same 265,000km of hybrid car, you are goign to fork out an additional $15000 of electricity. over 10-15 years, additional maintenance of the hybrid is likely to be about that in services compared to the electric. of course at some point the battery will die !! and ten now the electric car is really, really expensive !!!! So , small battery electric for city daily use makes good sense right now, but payback on the large battery EVs seems nonsense. so, Toyota's strategy of the hybrid is good right now me thinks, just not explained to the publix or pundits
×
×
  • Create New...