kortopates

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kortopates last won the day on December 12 2019

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About kortopates

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  • Birthday January 21

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    San Diego, CA
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    252AV
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    M20K 252/Encore

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  1. Savvy is Making Breakdown Assistance FREE During COVID-19 Lockdown It only takes about 2 minutes of your time to sign up for FREE breakdown assistance for the next 3 months through June 30th by going to this page: https://www.savvyaviation.com/savvybreakdown-special/ Note Breakdown assistance is for when you are travelling away from home, not for assistance at your home base, and begins with any location at least 50 nm away from your home base. See the terms/conditions for further details but I believe that is the only restriction. Our philosophy behind Breakdown assistance is to get you home safely where you can use your ordinary maintenance providers with the least delay and need for costly away from home maintenance; especially now when many providers are closed due to the pandemic. Existing Breakdown Assistance can get an additional 3 months added to their subscription for Free by contacting us at https://www.savvyaviation.com/contact-us/ I am also hearing the 50 nm ring around your home base is being relaxed as well, just during this period to June 30th. Our assistance includes world wide support!
  2. Is your ramp really on a slope of 2-3 degrees to the left as it suggest? You could put a digital leveler laterally across the seat rails and compare that to what your Aspen is indicating for a quick and easy comparison.
  3. Great explanation on the mechanism behind lubrication and how important turbo speed is to effective lubrication. WRT to TIT, they cool down as soon as we reduce power on approach, either from pattern altitude or from the FAF. A leaner mixture than rich helps to keep them a bit higher as well as the CHTs for a possible go around, but the reduced power cools them down on the final approach rapidly to below 1200F slowly decreasing to near 1000F. By the time we're landing they are at their minimum which is below 800F, and as we taxi to the hangar they'll actually go back up closer to 900F. Idling at this point isn't going to get them much cooler and not as cool as at landing. This is the basis of the rational for why a further cool down isn't needed despite the POH warnings calling out for a 3 min cool down. In your explanation of bearing wearing primarily "start and stop events when the speed is less than lift-off speed," is the "lift-off" speed a turbo RPM that bearing and rotor shaft separate? and if so any idea if we might approach that at a typical idle RPM? Or is repeated idling in the run-up area waiting several minutes for a IFR release well below this and similarly what Paul's @gsxrpilotcomment above about the cool down actually does more harm than good by contributing to significant bearing wear?
  4. I agree with you there as well as APS advice on the topic regarding the need for the 3 min cool down before shutdown. I was quoting the article for the flushing procedure. Are you also asking or wondering if coking is a myth as well? I have no reason to doubt the Turbo re-builders, such as Main Turbo, that continue to see it as an issue. I just don't trust it comes from the shutdown procedure. I have wondered if its happening in flight slowly with excessive TIT's but I really don't know.
  5. Thanks! Here is a step by step procedure from RAM: http://www.ramaircraft.com/Maintenance-Tips/Save-A-Turbo.htm
  6. Mike, you are so right about TIT. I was editing my my response to correct that oversight while you were writing your reply. But absolutely TIT plays a very important role by increasing the wear rate as the TIT climbs to higher temps. The turbo charger is already glowing with cherry red color at 1550F yet TIT limitations are another 100-200F higher than that. Most of the earlier turbos have a TIT limitation of 1650F while some of more modern designs, theoretically with better metallurgy, have pushed that up to 1750F. Yet even with those, we recommend not exceeding 1600F to improve turbo and other exhaust component longevity. I should back up a bit though begin with the different controllers used to regulate the upper deck pressure (UDP) since different controllers influence how hard the turbo is working and then go into more detail about what wears out in the turbo and what causes it. Some of the controllers strive to maintain a constant UDP a few inches above redline MAP regardless of how much MAP you're maintaining. This is one fundamental reason why MAP alone doesn't influence wear. An example of this is the Absolute Pressure Controller (APC). Imagine in this case, flying with lower MAP isn't helping reduce the turbo output since it trying to maintain a constant set point UDP. In fact as the pilot reduces power, the controller will increase oil pressure to close the wastegate to force more exhaust through the turbo to maintain UDP at the desired constant. A better controller used by most pressurized twins, and my Mooney, is the the Variable Absolute Pressure Controller (VAPC). The variable part of the controller is that it no longer strives to maintains as constant UDP but variable one limited too a couple inches over the required MAP setting. At full WOT it operates just like a APC, but below that its variable to be just above the required MAP. As such its not working nearly as hard as the APC type. Moving onto wear points. We find the turbo fails or exceeds limits in two principal areas, i) the garlock oil shaft seals on the shaft connecting the turbine to the compressor and the i) the compressor blades. The spinning turbo shaft is constantly cooled with oil pressure fed from an engine galley and then scavenged back into the engine case with a separate oil scavenger pump. The turbo shaft doesn't have anything like real bearings but only a metal shaft rubbing against a metal housing except the shaft and housing is pressurized with oil held in with a garlock seal which is also only metal. The shaft is spinning at very high rpms in excess of 50,000 rpm with only a film of oil to protect it. When the garlock seals begin to wear excessively they leak oil that is either pumped overboard out the exhaust or even worse into the induction stream out the compressor side; depending on what part of the shaft the seal is failing. Also as the seal and/or the shaft wears, the shaft develops too much free play which leads to blades touching the outer housing leading to accelerated blade wear and sometimes blade failure. The blade wear is the other common cause of turbo replacement. Blade wear due to excessive shaft free play is only one mode. Blade wear also stems from blade stretch which is directly related to blade temperature and the rotational speed of the blades which can well above 50K rpm. When rotating at very high rpm's at high altitudes and operating at very high temperatures blade stretch wears the thin curved compressor blades at a higher rate. The garlock seal is also under greater stress as shaft RPM increases, and temperature increases. In fact as the turbo ages, it suffers from some degree of internal coking from burnt oil that reduces the effectiveness of lubrication to prevent wear and hot spots. This is why its recommended to flush the turbo every few hundred hours to reduce coking before it gets bad enough to cause premature failure. Other indirect signs of the turbo working much harder at altitude is the significantly increased CDT or Compressor Discharge Temperature. CDT redline is a limitation on installations without a factory intercooler since too high of an induction air temperature significantly reduces detonation margin of the mixture. Down at low altitudes the CDT is never a concern but as we climb higher and higher the CDT goes up as the compressor has to breathe more air or spin faster to get to the desired MAP. Interestingly, another indirect sign is oil consumption. When the garlock seal is first beginning to leak it will first appear to the pilot as very sporadic changes in oil consumption. One flight it'll appear to burn a quart or more of oil over a relatively short flight, such as 1-2 hrs. Then no oil consumption at all for several flights. And then excessive oil consumption returns on another flight, frustrating the pilot. What's happening is that the garlock seal is wearing out but at lower altitudes, say 6-10K, the turbo is hardly spinning. But take the plane up to the upper teens or flight levels and now the turbo is spinning much faster since its compressing air nearly only half as dense and with its great increased rpm its pumping a lot more oil out the shaft. There are other turbo failures not really related to how hard the the turbo is working or how hard the pilot may be pushing it which I didn't go into, such as blade erosion. The quickest way I know of on how to ruin a perfectly good turbo is to run it up on the ground with alternate air door open (which can pop open on its own; especially if de-cowled for maintenance) or even worse de-cowled with no air filter on it and it then sucks in some light FOD ruining the compressor blades - ouch! sorry, didn't mean to write such a lengthy reply but its a great question!
  7. What was the objective of your test flight?
  8. MAP alone isn't important, its high MAP and high altitude that makes the turbo really spin or work. Add in high TIT to increase the wear rate. I should add, 1200 hrs on your turbo is doing great. You're obviously taking care of it.
  9. The Prelim came out this past week but unfortunately it was not much more than a recap of the tape we've already reviewed. It does add that the plane hit a power line 50' above the ground which led to it landing inverted 250' down slope of the lines. You can read it here: https://app.ntsb.gov/pdfgenerator/ReportGeneratorFile.ashx?EventID=20200313X13202&AKey=1&RType=Prelim&IType=FA The location of the site was the same as was reported elsewhere within a few days of the accident just west of a land fill.
  10. If the E5 doesn’t pan out, have you considered a pair of Garmin G5's? Supports dual bearing pointers for about same cost and should also support any of the K autopilots with the GAD29b. Sent from my iPhone using Tapatalk
  11. I can't answer your specific question. But keeping the KI-229 makes no sense since the Aspen HSI includes dual bearing pointers. That's where the functionality is most useful, where you can see the bearing pointer(s) with your HSI in the same spot. I gather you're new to glass. I'd encourage you to read the pilots guide to learn more about all the functionality but if I was in your shoes I'd be pulling the KI229 unit since you won't need it with the Aspen.
  12. The FAA has granted a 3 month extension to end of June for renewal of medicals. Airman Medical Certificate Policy.pdf update: Its also on AOPA here: https://www.aopa.org/news-and-media/all-news/2020/march/27/faa-eases-pilots-worries?fbclid=IwAR3HY4s1eOXw9NJBdlxYBbUyOSuV4K4QFfs4vPkWz54qVsEjkFGChGBLThU In addition to this, we're see very recent AD's getting extensions for compliance as well. Although nothing of interest to a Mooney owner to cite. But nothing on the Flight Review extension request as of yet that I have seen. But perhaps any relief might follow a similar blanket extension as given in the Medical Certificate extension.
  13. In California, not withstanding a handful of counties around the Bay area that apparently have more stringent shelter in place guidelines, our state guidelines totally exempt the Aviation Sector as essential even including flight instruction and recreational aircraft use. I had a Commercial student just complete his Checkride since our state wide shelter in place order became effective and the DPE had no issue doing it. On expiration of flight reviews, I can imagine the FAA allowing pilots with expired flight reviews to fly solo VFR to get to their CFI for a flight review. Check your insurance policy to make sure you are still covered without a current flight review. (I believe I am on mine, but with all the changes recently such as dropping open pilot clauses I'd want to check again). I personally only do Wings Flight Reviews these days. It really is in the best interest of the client. First you do the ground on your own online with lots of free courses to pick from. Anyone that attends Wings seminars will have this requirement already partially completed as well. Then we fly the Wings flight activities together which gets you bonus points should the FAA ever want to talk to you regarding a possible Pilot Deviation. If you get called in, the first thing they do is check your Pilot history. When they see your Wings activities they immediately recognize you as one of the good guys that take their currency training seriously. Also, Wings participants are less likely to get called into the FSDO than those that don't participate in the Wings Pilot Proficiency Program.
  14. I assume you meant new Crank, since Cams are cheap. The problem with cranks is that they can only be turned a few times and then you have to buy a new one for several thousand - I am not even going to guess how much exactly as they are expensive. But you can check Spruce's prices for crankshaft here and see how expensive they can be : https://www.aircraftspruce.com/catalog/eppages/lycoming07-14058-96.php You also have the option of finding a used or reconditioned salvage crankcase. They exist but finding the one you need when you need it can be a challenge. But these are pretty popular/common engines.
  15. I believe we just have to look at Italy to see this is not at all the same as the our annual flu season. For starters we have flu vaccines such that most of us don't get the flu every year. We won't have similar protection for COVID-19 for possibly up to another 18 months. This morning on the news they were reporting the number of deaths from COVID-19 in Italy has far surpassed their ability to dispose of the bodies. Far beyond what they see for a normal year from flu deaths. Check this page out for some quick chilling statistics: https://www.worldometers.info/coronavirus/country/italy/