Jump to content

Yenn

Members
 View Profile  See their activity

  • Posts

    6,616

  • Joined

  • Last visited

  • Days Won

    31

 Content Type 

Everything posted by Yenn

  1. Yenn
    I agree that poor decision making is the major cause of accidents, not only in flying, but also on the road. The use of personal minima always seems stupid to me. If we set a minimum visibility for ourselves, how do we know when we get to that minimum while flying. It may be OK for the forecasts, but they are not always correct. What is this about no met training Turbs? Are you saying that RAAus pilots don't get met training. If so something is seriously amiss. I don't know RAAus standards as my training was GA not RAAus and back a few years and from what I see it appears that GA pilots are trained to a lower standard nowadays.
  2. Yenn
    It won't make you a better pilot either.
  3. Yenn
    When you get that low I wonder how much good a machine like that is going to be. On my usual runway I would be getting heights like 10' 5' 3' 3' 2'1'T about half second intervals. The ground at the approach end of the runway is quite steeply up hill, then flattens out. The heights from the other end would be altogether different, due to its gentle downhill slope and then again a level runway would be different again. A bit too much for me to analyse quickly, but I seem to handle it OK using eyesight only.
  4. Yenn
    This is the standard working principle of most pumps, but unfortunately it is not understood by many who should know better. I recently read an article in a magazine by someone who should be fully conversant with that type of pump, as used in a Jabiru. He said that he had fixed a fuel pressure problem that others could not fix, by changing the stroke length. I never got round to asking how he could explain the theory and the SAAA magazine has gone into storage while I move house.
  5. Yenn
    mounted horizontally (in relation to the engine) What does this mean Skippy. Is it horizontal or not and what does it's orientation to the engine have to do with it? It seems that people nowadays mix up horizontal with parallel.
  6. Yenn
    What is meant by you can't design an Otto engine without an ignition system, or maybe I should ask. What is an ignition system? The Otto cycle includes both normal petrol and diesel systems, Diesels don't have an electrical system for ignition. They compress the charge so that it's temperature becomes hot enough to ignite the diesel, when it is injected. Diesel power is controlled by the amount and timing of injected fuel, whereas petrol power is controlled by the amount of air in the charge and the ratio of petrol to air. The old diesels had a bad reputation for sooty exhaust, which was caused by injecting more diesel than the engine could burn with that air. Old diesels also did run slowly and when Perkins introduced a high speed diesel it was still less than 3000rpm. Over the years i have come to prefer diesels for their ease of operation. No worries with electric ignition, nor with a carburettor, but they are not generally designed for what we need to pull an aircraft along. A friend of mine has flown the twin Diamond with diesels and liked it, but there are not many of them around.
  7. Yenn
    Student. It looks as if your instructor is not doing his job. He should have checked W & B and also found the disconnected trim during the pre flight.
  8. Yenn
    To come up with some answer to what happened when you don't know what happened is stupid, but it also shows others how reliable you are. I prefer to keep my mouth shut and be thought a fool, than to open it and dispel all doubt.
  9. Yenn
    If you are doing your finals turn at less than 500', there is a good chance that you are going to be influenced by the ground and if you are going downwind will get a false sense of speed. You will not be wanting to look at the ASI, because the ground is near, so there will be a tendency to pull back to slow down, resulting in the stall.
  10. Yenn
    Back in the sixties i was working on a chimney at Jurong in Singapore and the jets used to come into the nearby airport right alongside us. Sometimes one would roar past on the wrong side. I assumed they were doing instrument approaches and had the occasional go around.. Nice to look down on them.
  11. Yenn
    It all depends upon the plane, but whatever happens it is most likely better to be recovering from a stall when you crash, than fully stalled.
  12. Yenn
    FRguy stated' Stall speed is the square root of aircraft weight ratio, (all other things being equal) , if the aircraft stalls at 50 kts clean at 600kg, then (all things equal) the stall at 430kg will be sqrt(600/430) or 1.18 times lower , or 42 kts. The Va for 600kg might be 90 kts, and will be that ratio lower at lower weights. I was always under the impression that higher weights resulted in higher stall speeds, so I reckon there is something wrong here, which leads me to suspect the whole argument delivered. If stall speed varies at the sqrt of weight changes, by my reckoning stall at 430kg would be 59kts.
  13. Yenn
    That idiot Turnbull and the LNP aren't even aware that it was their poor decision making and later realizing their mistake that caused the fallout with France. I wonder who is making the decisions now, because just looking at the latest wars it seems that fighter jets are an expensive plaything. A much more useful tool would be drones and how many of them could we buy for the price of one fighter jet, plus how much would we save on pilot training.
  14. Yenn
    I used Autocad at work, years ago and have tried other types since. never heard of DeltaCad. I like to do woodworking designs and mapping of my property and water mains etc, so will have to give it a go. All the others I have tried are very hard to use and don't even have relevant how to do it pages.
  15. Yenn
    That doesn't look like a near birdstrike. Much closer.
  16. Yenn
    Typical of Australia we purchase an in development aircraft and then contribute billions to an unknown performer. Just have to hope it will work.
  17. Yenn
    I would like to see that Savvy flying backwards.
  18. Yenn
    I was obviously wrong about the nosewheel weight, surprised that it is so heavy, but that is no doubt the reason that nosewheels get damaged so often.
  19. Yenn
    Why the comment about tail wind. That would only have had any bearing on the crash if the pilot had been flying in relation to the ground and with no regard to airspeed. I would not expect a pilot of the quality required for that sort of job to be unaware of the need to disregard the false impression of speed when flying with the wind.
  20. Yenn
    Turbs. Do you know what the recommended weights are for the J200. Even if the prop was twice as far away from the datum I reckon it would be hard to lift. I can't find the relevent numbers quickly. I think Jabiru use the leading edge of the wing as datum and I would assume recommended c of g would be about 300mm or so aft of that, or 25% of chord, so there would be a fair distance between nosewheel and c of g, all multiplying that 65kg.
  21. Yenn
    I am not a Jab flier, but to me 65kg on the nosewheel sounds a lot. I have not found an aircraft that I couldn't lift the nosewheel a bit by lifting the prop, but 65kg would mean that the prop would be very hard to lift. Check the POH to see what their weight and balance figures normally are. You may need to do a W&B anyway as part of your restoation.
  22. Yenn
    There are at least 5 types of ironbark used in Qld, all very similar, heavy and hard. Resorcinol was used for years for boat building, especially for double diagonal planked hulls. I built one and was amazed at how tough the hull was. I used epoxy for building my Corby and it has had no problems over 22 years of flying. The use of carbon with a wooden frame in an aircraft would have to be very thoroughly designed. The timber part would not get any loads until the carbon yielded, then it would take all the load.
  23. Yenn

    Xplane 11.55

    Yenn replied to RFguy's topic in Flight Sim

    The RV4 and Corby files went years ago. I made them using X Plane and just filling in loads of details as it required them/
  24. Yenn

    Xplane 11.55

    Yenn replied to RFguy's topic in Flight Sim

    I used it many years ago but that computer died and I got poorer quality computers. Now I am put off by seeing what X Plane supposedly needs to operate. I made a Corby Starlet for X Plane and it flew exactly as the real one, but I couldn't take off or land without losing control. I don't know if it was because I didn't have rudder pedals, only the left / right arrows or something else. I also made an RV4 before I did the test flying in the real one I built, again very true to life, but I couldn't handle the rudder on the ground.
  25. Yenn
    Maybe others don't contribute is because the arguments proffered are ridiculous.
×
×
  • Create New...