jaylw314

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About jaylw314

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  • Gender
    Male
  • Location
    Oregon
  • Reg #
    N1999W
  • Model
    M20J

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  1. jaylw314

    It might be overhaul time...

    Off-topic, but can you pull the lifters in Lycomings with roller tappets easily?
  2. That's the one! I really have to remember to bookmark that
  3. jaylw314

    FASTEST?

    The 3-blade prop WILL have less blade pitch, since the prop speed is governed. the only time both would be the same is if both are against the same high-pitch stops or the same low-pitch stops, e.g. low power with prop forward on the ground or high power in a screaming dive with prop back. Power = Force x velocity = blade lift x blade speed (roughly) If you have a fixed-pitch 2-blade prop on an engine that makes 100 hp at any RPM, then stick a 3-blade prop on it, the engine will still make 100 hp, because that's all the engine can produce. However, it will only require 2/3 the RPM, not because of drag but because it does not need to spin as fast to generate the same force. Of course, now we're talking about a hypothetical engine that doesn't exist, so not a very useful example... There certainly can be interactions between blades if they are "cutting" through the same air, but if the plane is moving forward, each blade does not pass through the air from the previous blade. IIRC, this can be an issue with helicopters if the descend through their own airflow, but planes don't fly backwards. And I'm just a layman too, not a mathematician or engineer
  4. Dang it, does anybody remember the link to the Lycoming SI about troubleshooting metal in filters? The long story short--if it's more than a 1/4 teaspoon of metal, you worry. If it's less, you just watch. With the recent overhaul, it's not surprising to find some metal early, although I think (or guess, rather), that it depends on how many parts are replaced.
  5. jaylw314

    Backfire on short final

    If it's a new thing, the warm summer temperatures might be contributing?
  6. jaylw314

    FASTEST?

    Yup. Just like loading your car with a bunch of heavy crap doesn't change the mileage much on the highway (since most of the friction is air resistance), but it takes longer to get up to speed. But I think yes, a 3-blade prop that has the exact same blades as a 2-blade prop will require 50% more power to maintain constant idle RPM (when they are at the same pitch). At full power, though, the engine is producing excess power to move the plane (and make more noise), so that difference will be much smaller, e.g. if 180 hp goes to moving the plane and only 10 hp to keeping the 2-blade prop spinning (190 hp total), the 3-blade prop at the same pitch will require 15 hp (195 hp total). Of course, the 3-blade prop will actually be at a LOWER pitch and produce less induced drag, so that difference would be even less. If anything, heavier props have an advantage in dampening vibrations and sustaining momentum for things like helicopter autorotation landings (obviously not a help to us). They only suck because of the increased weight and increased weight up front.
  7. jaylw314

    FASTEST?

    Why did the go through all that trouble to modify the cowling, and then stick a massive honking muffler out in the wind??
  8. jaylw314

    I'm not sure who to believe

    Crap! I'm glad you're okay! I joke with people that I still can't find my seat cushion after that icing incident, but with that I might have sucked up the entire seat!
  9. jaylw314

    Braking After Landing

    Conversely, it's hard to imagine a scenario where old brake fluid would get hot enough for long enough to boil off moisture. At worst, we might stand on the brakes for what, 10 seconds? The rotor will get hot, but I can't imagine there's enough time for the fluid to heat up in that time. Afterwards, sure the brake fluid might heat up enough to get water vapor bubbles, but by that time you're taxiing. It's not like automobile brakes where you might be standing on the brakes multiple times in a row. Old fluid might cause corrosion from the absorbed moisture, but I can't imagine it would realistically affect braking performance.
  10. jaylw314

    Governor Options

    It will fail to high RPM with loss of pressure. some multi-engine hubs are designed to fail to low RPM or feathering, but I suppose it's theoretically possible for even those to fail to high RPM
  11. I'm guessing when you switch tanks, while the switch is in between tanks the pressure in the fuel lines start dropping, with maybe the possibility of cavitating or introducing air? Seems unlikely if you switch quickly enough though.
  12. Does the engine driven fuel pump suffer if it is pumping air?
  13. jaylw314

    Braking After Landing

    By that same token, NOT being able to lock up a wheel would be a good measure of a really crappy brake!
  14. jaylw314

    Landing Light Wire

    I checked the M20J parts manual, I couldn't find any references to landing light wires, so I'm not sure where that would be written down (if at all)? I'm not sure, but I think all M20's with cowl landing lights have the same wiring and those clasp-knife connectors, right?
  15. jaylw314

    Braking After Landing

    Before, I was actually taking a picture with my smartphone from above, and then looking at the pictures. Now I'm too lazy to do that, so I probably won't go the endoscope route