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Guitarmaster

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Everything posted by Guitarmaster

  1. I applied to do this about three months ago and have heard nothing. How long does it take for them to get back to you? Sent from my iPad using Tapatalk
  2. "There is just one trick, DO NOT open the storm window with it turned on. It senses cabin pressure to determine altitude and opening the window will give you a full down elevator deflection." Now THAT is need to know info!! Sent from my iPad using Tapatalk
  3. I don't know where the boundary is. It might be well past 40 degrees. I just know the timing would be advanced and ICP increased with a low rpm/high MP cruise. A question... Are the internals for a turbo engine different/beefier than for the naturally aspirated? Sent from my iPad using Tapatalk
  4. There are two kinds of negative torque. When the plane is driving the prop, but also in the engine itself. The engine is nothing more than a big air pump. I my case, 360 in3 per stroke. On the intake we inject fuel and air. In the case of our airplanes, that fuel/air mixture is lit off at 20-25 dBTC. In other words, flame propagation starts there. Because of this fact there is a certain amount of gas expansion prior to TDC trying to push the engine backward. Negative torque. To have no negative torque, you would have to start flame propagation at TDC, but this is inefficient as the flame chases the piston down and most of the energy goes out the exhaust. This produces high EGT. As the timing becomes more advanced, flame propagation and expansion begins sooner and EGT decreases. The more advanced the timing, the cooler the EGT. BUT... since energy cannot be created or destroyed, it has to go somewhere. In this case, ICP and CHT. Ideally you want the maximum expansion just past TDC. Easy to talk about, not so easy to achieve. I can't say for sure, but I would guess Lycoming sets this at maximum RPM and MP at sea level standard day. If you slow the engine down, and increase power, you are running at a high load. Like pulling a trailer up a hill in sixth gear. Since the timing is not variable, the flame propagation begins much earlier in the stroke. This will naturally show a decrease in EGT and you will have a increase in negative torque. So, the real question is, how much can these engines take? The only real way to tell if you have passed the "equal torque point" where negative is greater than positive, is to dyno the engine at different load settings. This is based on my years of experience tuning automobile engines. However, all internal combustion engines work basically the same. Sent from my iPad using Tapatalk
  5. Congrats! Enjoy the new found freedom in the IMC environment! Sent from my iPad using Tapatalk
  6. I have lots of time to think at FL410 for hours on end. My thoughts for today. I tune my truck myself. Under high load (high power, low RPM). The timing is retarded to near 0 dBTDC. Under light loads, the timing is more like 20 dBTDC. The reason is flame propagation and internal cylinder pressure. Quite simply, there is always negative torque in an engine, of course, advancing timing increases this. The trick is to get the perfect balance. Theoretically, this can be done with computer controlled timing. Since our airplanes, as I understand, have a fixed timing (except for start), then low RPM with high power will increase ICP dramatically and at the same time, decrease EGT. without a doubt, this will increase power until you get to the negative torque region, then you have problems. The real question is, how much ICP will these engines take? Sent from my iPad using Tapatalk
  7. Thanks for the recommendations! I have a quote from David (who I have heard good stuff about) but wanted to do a little comparison shopping. Sent from my iPad using Tapatalk
  8. Just thought I would add my two cents to the discussion. As a new instructor years ago, I had a student who bought a 65C and wanted me to teach him to fly in it. Being the young dumb instructor, I took the job. The power off stalls fully configured were predictable but slightly uncomfortable. Watch out for that secondary. Power on stalls however, were a drastically different story! power on departure stall resulted in uncomfortable nose up and then, without warning, Instant break to the right and we were looking at the world upside down! This was much to my surprise. It recovered quickly with abrupt and full controls. Now, the interesting thing. In order to keep the ball centered, I needed to have almost full right rudder. This of course made it an uncoordinated stall. Hence the spin entry. The conundrum is, if I had not pushed full right rudder, the ball would've been hanging out to the left. This would, of course, produce a left turning spin. I have not and will not do a full power stall in my F. It's not really a big deal IF YOU ARE EXPECTING IT. If you are not expecting it, it happens VERY fast with NO warning. Now, the C that I flew didn't have stall strips so there will probably be more warning in my F. Cheers! Matt Sent from my iPad using Tapatalk
  9. I have huge interest in this subject. Curious... Mike Busch's article on plain bearings was very enlightening. What I took away from it was when the engine is running, there is essentially no friction on the mains due to oil pressure. The real wear comes from startup just before pressure rise. Hence the reason to not use synthetic oil. It seems to me, as long as you have good oil pressure, the bearings should not be an issue... To a point of course. I think I would be more concerned with connecting rods and pistons. However, as long there is no detonation, I can't see low rpm being an issue. When I get a chance I am going to talk to the excellent engine shop we have here on the field and see what they have to say. Admittedly, OS scares me a little. Probably my own carryover biases from years ago. I am always looking for new and possibly better ways to operate my airplane. Cheers! Matt Sent from my iPad using Tapatalk
  10. Hey all... My '75 F model is in need of a new nav/com. Looking to the GNC255 or GNS430W. I need some recommendations. I'm located in northern Illinois, but willing to travel for the right shop. Thanks! Matt Sent from my iPad using Tapatalk
  11. Cool. I learn something new everyday!! Even if I don't want to! . Lol! Sent from my XT1080 using Tapatalk
  12. Bonal... I did check that and no play found. Thanks for the heads-up! She is very low time (1700 hours) so I didn't really expect to find any. Clarence... I am not 100% sure! but I think it is around 3500 - 4000. With the exchange rate though, that's probably about 8000 Canadian.. Sent from my iPad using Tapatalk
  13. There are two small screws in the bottom of the boot that are all but impossible to remove without disconnecting the piano hinge. Yes, I plan on doing the owner assisted annuals as well as all the work to my plane under A&P supervision as all that time can be logged to getting my A&P. I really feel, if you are mechanically inclined (i am) that an owner maintained airplane is the safest. Simply because you don't tend to let things go until annual. Only the owner can detect the slightest "oddity" from normal operations very early on and take care of the problem. If nothing else, you can diagnose and possibly save some money at the shop
  14. Here are the pics of the panels I removed. I took her out for a test flight and all is well with the trim now. 195MPH hands off! The second pic is the plate that will give you access to the jack screw. The other one gets you to the torque tube. The third shows the boot covering the jack screw.
  15. Hey guys. Just wanted to pass along what I found while searching for my "running out of trim" problem. It would seem there was old, semi-hard grease causing an artificial stop and would not allow the trim to go fully down, or up for that matter. Cleaned very well and re-greased. Trim now will roll stop to stop smoothly. I haven't had a chance to fly her to see if it fixed the problem, but the trim wheel rolls down an additional four "palm strikes" now so I have to assume all is well. I am thinking whoever did the annual on her before I bought her may have been a little lax. Here are the pictures of what I pulled out of the tail.
  16. I just had a intermittent KT76 transponder issue. Sometimes it would work and others it would not. Sometimes cycling would work, sometimes not. Turned out to that the transponder was out of alignment. What I learned is the frequency has a "width." If your transponder wanders more than three degrees and ATC is off a few degrees the other way, ATC radar will not pick you up. $170.00 to realign. Works perfectly. Sent from my iPad using Tapatalk
  17. Wow! I am so green with panel envy!!! Sent from my iPad using Tapatalk
  18. Do the pre-buy WITH the mechanic. Ask questions. Search this forum for known problem areas (stub spar, tubular corrosion, nose truss). Pull all the AD's from Mooney's website and become familiar. They are a tough read, but you will learn LOTS! I bought mine about a month and a half ago. It was overhauled in 1997 and only flew 12 hours since. It was a gamble, but after talking the the good folks at the local engine shop, i decided it was a low-risk purchase. Avionics are a big deal. Mine are original to the plane. One is weak, but the other works fine. When they quit, it's about $5000 per radio. GNS 430 is about $11000. In 2020 (maybe) all planes will need to have Extended squitter transponders. Of course with all things FAA, there is no way to make a 2020 deadline a reality. Anyway, to upgrade to Aspen, GNS430W, additional Nav/Com, ES Transponder will be about $25,000…. of course she will have a nice rack (of radios) after all that! Go with eyes open, but don"t get paralyzed in the analysis. Eventually you just have to plug your nose and jump in with both feet! You will be glad you did!!
  19. I have the same issue (not enough down trim) with my "F" when I hit around 175MPH indicated. Could use a little more up trim on the landing also. However... I did notice the plane is very close to the FWD CG limits with the two front seats occupied so it kind of surprises me that nose-down trim is an issue. It does land considerably easier with my two not-so-small kids in the back. At full nose-up trim, the indicator falls somewhere between the TO and NOSE UP position. I find that a little odd.
  20. Thanks Don. Sent from my iPad using Tapatalk
  21. What are you guys using for a fitting on the top of the reservoir? I am reasonable sure I have a big bubble in there somewhere and need to be able to pump through the caliper and be able to see the bubbles as they exit. Would it be possible to use a vacuum bleeder attached to the reservoir to pull the fluid rather than push?
  22. Thanks everyone for your input. Chris, I like that feature also. Right now I am leaning toward the Garmin, but I like the flight planning with FF. Side note... I have a friend with a "J" that puked the vacuum pump yesterday. He had just flown out of IMC conditions so it was not a big deal... Could have been a huge deal 15 minutes earlier. I am really liking the built in AHRS right now. Sent from my iPad using Tapatalk
  23. Hey all. I have been flying with Foreflight and Garmin Pilot. There are some old ads-b threads, but with the new tech, I need some opins. First, I have a mode s transponder. As I understand it, this qualifies as the 2020 requirement for "ads-b out." Now, both systems say they they receive TIS-b, but the Garmin says it receives feed from the ATC facility as well. The main and only gripe on the Garmin was the use of BT instead of WiFi. He said it kept dropping the signal. They are the same cost. I like Foreflight, but I could get used to Pilot. I am not looking an any others at this time. Thanks in advance for your input! Matt Sent from my iPad using Tapatalk
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