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PT20J last won the day on March 2

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    1994 M20J

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  1. Thanks, Don. That's how I thought it worked, but I couldn't find it in the documentation except a statement that the altitude bug has to be set at or below the lowest altitude constraint that kind of implies it.
  2. The Garmin avionics can be confusing because the documentation doesn't usually explain the underlying theory of operation and also because Garmin avionics can be used in a variety of configurations and with different installed options. One thing to keep in mind is that the GTN is ALWAYS a GPS navigator. Even on a VOR or ILS, the GTN is using GPS and the missed approach is always GPS. The GTN includes a Nav receiver, and if you switch the CDI to VLOC the external CDI will display the VOR or ILS and the autopilot will track it, but the GTN is still using GPS and that's why the map course line is magenta and the distances are valid and why the GTN presents a splash screen when you select a non-GPS approach warning that it is advisory only. In other words, the GTN is not supplying navigation, the Nav receiver within the GTN box is supplying navigation. Also, the GFC 500 requires a valid GPS source even to fly a ILS or VOR approach. In my airplane, I have a G3X, G5 and GTN Xi. If the GTN fails, the G3X GPS will drive the autopilot and if the G3X fails the GTN will drive the autopilot via the G5. It would be good to make sure that any installation has more than one GPS source.
  3. Let’s say you are on a GPS flight plan with the autopilot engaged in NAV ALT at 8,000 ft. Ahead is waypoint A with an altitude constraint of 7,000 and waypoint B with an altitude constraint of 5,000. You are cleared to descend, pilot’s discretion to 5,000. You set the altitude bug to 5,000 and hit VNV and the autopilot captures the vertical track at TOD and descends and crosses A at 7,000. At this point, you are told to cross B at 6,000. If you set the altitude bug to 6,000, will the autopilot stop the descent and switch to ALT at 6,000?
  4. What I need is a post flight analysis tool that tells me what setting I got wrong or button I failed to push at the appropriate time when the automation doesn’t do what I expected
  5. Details of the servo trim chain tension are in the autopilot installation manual. If it is a KAP/KFC 150, it is supposed to have only 1/4” deflection. The trim carrier bearing (again, if you have a B-K autopilot) should be lubricated per the maintenance manual. The boot covering the jackscrew is pretty tough. Run the trim all the way nose up and remove the 4 tiny screws at the forward end and slide it back. Clean all the old grease off with solvent and apply new grease.
  6. Don, I marked up your scenarios to show what happens if the Remote Go Around is connected on the GTN Xi:
  7. If they don't retract, there is some mechanical problem and you will need to remove them to figure out what's going on. The devices are very simple -- it will be obvious. If you need to send them to Precise Flight for repair, be ready for sticker shock. There seems to be two issues with lubricating these thing:. 1) they never get lubricated, or 2) they get lubricated using the theory that if a little grease is good, a lot must be better. When Precise Flight overhauled mine, they came back all cleaned up with a little dab of grease on the worm gear. It doesn't take much. Too much grease just makes a mess and attracts dirt.
  8. Is there a spec for rudder play for the C? On the J, the only spec I can find is for vertical movement (jack screw, trim link wear check). I cannot imagine that a little play in the rudder would affect flight characteristics -- it will only increase the dead zone where the rudder floats and pilot rudder inputs are not nearly as precise aileron or elevator inputs, so it would have to be really sloppy before you'd feel it. I would make sure that it is really out of some published limit before going to all the trouble to replace the rod end unless the rod end is so sloppy that it is in danger of failing. Because of all the play in the linkages, they all have some play at the rudder. If you are trying to measure it, be sure to clamp a bar across the rudder pedals to eliminate the play in the steering linkages.
  9. TOGA (Take Off and Go Around) is an autopilot function. It commands wings level and default climb pitch. (Note that Garmin actually calls this function "Go Around", not TOGA). Missed approach navigation is a GTN function. There is an installation option to connect the GFC Go Around button to the GTN to cause the GTN to initiate missed approach guidance. But the two functions are otherwise unrelated.
  10. You can check it on the ground. The installation manual has a procedure. You can get the G5 installation manual from the Garmin website. https://static.garmin.com/pumac/190-01112-10_30.pdf. See page 212.
  11. The reason that the GFC 500 does not go into NAV mode when TOGA is activated is that it has no idea what your missed approach clearance is. In a radar environment, it is common to get missed approach instructions from ATC which differ from the published procedure. Also, missed approach procedures that are based on ground based navaids will have an alternate procedure designed for the case where a ground based navaid is OTS and these alternate procedures are not in the navigator database. https://aerospace.honeywell.com/us/en/about-us/news/2023/05/alternate-missed-approach-procedures#:~:text=If a navaid used on,primary navaid is still available.
  12. I had to do that on my KC 192. The avionics tech that fixed an intermittent problem with between my GI 106 and KX 165 taught me that.
  13. Check the schematics in the manual I posted above. With an AA80 InterVOX intercom (which is what I assume you have) each of the four primary phone jacks goes directly to the ICS, so there should be a shielded twisted pair to each jack: one wire connected to the tip and one to the sleeve. I agree with Eric that it sounds like a connector problem now that more things are failing. If you have a KMA 24 audio panel the three lugs on a strip at the rear of the tray on the upper left side (facing forward) are indeed grounds and the wires should be resoldered. Probably a dumb question, but are you making sure to turn the front panel screw on the audio panel all the way in so that the panel makes good contact with the connector? Again, if it is a KMA24, the rear connector on the tray mounts with two screws from the front. I would check that the ears on the connector where the screws go through are not broken allowing the connector to be pushed out of position when the audio panel is screwed in. King used PCB edge connectors for the Silver Crown avionics and I have found that over time the pins on the tray connector sometimes don't make good contact. With the audio panel out you can access the connector through the opening in the top of the tray and use a small flat blade screwdriver inserted between the plastic body and each pin to gently push it toward the center of the connector so that it makes better contact when the panel is screwed in. I've had to do that with several different King radios.
  14. I don't know for sure, but it sounds like Dynon started the J and K together and then only recently realized that the F is like the J. But, although we think of the these planes as just one model or another, Mooney tended to make changes along the way and each one has to be researched and analyzed to determine if it matters or not. The reason the engineer came out to visit me is that I have a 1994 J and they noticed part number differences between early (of which they own an example) and later model Js. Sometimes the part number change has nothing to do with dimensions and sometimes it does. Also, sometimes apparently Mooney changed dimensions but used the same part number if the parts were interchangeable. You cannot tell without the manufacturing drawings which Mooney does not release. So they have to make measurements an actual airframes. In my case it was an elevator bell crank he was interested in, but he also noted that my rudder push pull tube is not the same diameter as the elevator push pull tube and in Dynon's airplane they are the same.
  15. It's not that they are picky -- it's the way the GFC 500 was architected. The software is distributed. Much of the software, including the flight director, resides in the PFD. Some of the autopilot software resides in the servos (Garmin calls them "smart" servos because they have a microprocessor and software). It's unlike a B-K or Century or S-TEC.
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