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Anticept

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About Anticept

  • Rank
    What's that red blinking light for?
  • Birthday 10/25/1986

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  • Location
    Columbus, Ohio
  • Interests
    Flying and fixing
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    Male

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  1. Anticept

    Two More Failed Ignition Modules

    Remember: a disconnected P-lead will activate that module. You need to ground the other one. The switch in the cockpit is designed to have both disconnected from ground on both and start positions.
  2. Anticept

    Max rpm or?

    I missed the part where he has a constant speed prop. It's better to run coarser for efficiency, but there's a point where returns diminish and it gets hard on the engine. There should be an operator's manual that came with the airplane (might be something in the rotax operator's manual too) that says what manifold pressures and RPM you should run at. In the case of an IO-360 engine that I had on my old mooney, at WOT, you couldn't set the manifold over square by much (When RPM/100 = Manifold in inches, it is "running square", running over square means manifold > RPM/100). But if you lowered the throttle just by a little bit, you could run over square considerably. Running 24 inches by 2200 RPM was very fuel efficient.
  3. Anticept

    Tubes

    The TR87 valve stem spec does not include a bend spec. People who buy these need to make sure the bend is also specified. You can commonly end up with a TR87 70 degree (these are great for other GA aircraft that don't use hubcaps) or a TR87 90 degree. On matco wheels on CTs, they are not interchangeable, people must make sure they are buying the 90 degree TR87!
  4. Anticept

    Max rpm or?

    Personally, I set the blade pitch for pattern altitude of my home airport. This is where the strain on the engine is hardest. There's not really a way for you to test lower altitudes without actually flying lower. I'm sure it would try to overspeed, not underspeed, if you flew from high to low. The higher you go, the less power you develop and the slower the prop turns. So you would compensate by flattening pitch. Flat pitch with lots of power means lots of RPMs. EDIT: Disregard, you were talking constant speed prop.
  5. Anticept

    Two More Failed Ignition Modules

    You can try it. You want to disconnect them from the trigger and charging coils, not from the secondary ignition coils. Make sure you get this right. Alternatively, remove the p-leads from the starter switch and ground them. Remove the ground from the one you want to test.
  6. Anticept

    She won’t start?

    It's a starting circuit peculiarity. Ice makes it work.
  7. Anticept

    Two More Failed Ignition Modules

    At the risk of jinxing, I've only had to replace a single module, and it's because the wires came loose from the board. Running one engine at 2400 hours, another at 2300, and still going strong on the modules. Two others were replaced at TBO.
  8. Anticept

    Generator whining over intercom

    It's only 12 volts. Don't worry about residual charge
  9. It would take HOURS to verify AD compliance on a lot of aircraft models. Aircraft ADs Engine ADs. Component ADs...
  10. This is actually an issue that is currently being looked at by FAA officials higher up the food chain. Some regions are not maintaining enough DPEs.
  11. Anticept

    Generator whining over intercom

    I use kemet ALS40A104KF025. Chanik here on this forum was the first to recommend it. Since then, I had passed this along to rotax, sportcruiser, flight design, and dynon avionics. You'll hear about this part recommendation if the original isn't cutting it. You replace the old capacitor with it. In the older rotax design, it is almost a necessity to install a capacitor that is 3x the minimum recommendation by rotax (this is coming from them in classes as well as field experience) to absorb electrical noise. The souce of the noise is the regulator recitifier's SCRs, or silicon controlled rectifiers, which are not properly noise suppressed. They act like gates that are constantly being slammed open and closed, and they are the common failure point as they are also switching very large loads (HEAT!). MOSFETs would have been a lot quieter... but also significantly more expensive (and I mean by orders of magnitude... SCRs are pennies, mosfets of this size are probably dollars to tens of dollars). I believe the 912i still uses a similar design, so they would also benefit greatly from a larger capacitor. Now, again, I want to drive home the point of grounds. Your electrical system is a lot like a water pipe system. It would be annoying if your municipal water system pressure constantly fluctuated. This is what your electrical system is doing. A capactor acts as an accumulator, which in the water equivalent, would be like having a water tower on your front lawn to absorb the pressure fluctuations. Corroded positive connectors would act like restrictions in the pipe, lowering your pressure, sometimes enough that some devices won't function. Now, ground connections are a little bit harder to use this analogy with, so i need to set you up first: imagine how an old water meter works. Water flows, pushing against a mechanical device. When you close the valves in your home, the pressure is still there (just like voltage, it's still there), but there's also pressure pushing back. The wheel doesn't move, so the meter doesn't run. When you open a valve, you lower the pressure on the far side, and water moves, acting on the wheel and moving the meter. If you have a restriction in your piping, the water flows slowly even if you have all your valves open, and the wheel moves slowly. It's because that restriction causes a pressure rise before it. When you have a dirty ground, it's like having a restriction. It raises the voltage in between the dirty ground and your device. So power won't flow as well, and some of it will dissipate as heat instead of being used to power your device. So point being, do a ground voltage drop test for your electrical system and see if you have a dirty ground. It shouldn't be higher than a few tens of milivolts, and when you turn on all of your electronics, you shouldn't see large swings in voltage. The larger the swing, the more it will translate to noise. The swings should never put it over 100 millivolts, but the less variation, the better! The regulator rectifier puts out noise and does cause some backfeeding on the ground, which is what the big capacitor is for. Your battery absorbs large power swings, the capacitor absorbs the small, rapid pulses that translates into audible sounds.
  12. Anticept

    Generator whining over intercom

    Won't really do anything. Use a larger capacitor and make sure grounds are pristine.
  13. Anticept

    ADS-B problem

    Because the wiring design is the worst part. A lot of hodgepodge half dones. There are wires using the shielding as a ground. While acceptable (barely), it's not preferred. Shielding is meant to be used as shielding, not as a current carrying conductor. And it doesn't have the mechanical flexibility of copper. The grounding design should have used a terminal block (pre LS) or ran a heavy ground to the terminal block and bonded to both strips (LS+) rather than used a bolt, which corrodes.
  14. Anticept

    LSA rules changing??

    As was said: The definition is changing. Your aircraft is not, unless the manufacturer makes the changes. https://www.avweb.com/avwebflash/news/LAMA-Higher-LSA-Weight-Good-for-the-Industry-231227-1.html
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