Ragsf15e

Good question, but that would be a pretty solid jolt to get outside 70 degrees bank or 50 in pitch (from the picture I attached above)!

Do you know the engagement limits?

Even the newer autopilots with “blue” buttons have engagement limits. So for example, outside of 65 degrees of bank or 30 of pitch (those aren’t exact, but ballpark from hazy memory), the gfc autopilot on a Cirrus won’t engage when you push the button. So there are limits. However, if you keep the esp function on, it starts bumping you back to level before you get a significant bank, pitch or airspeed excursion. my stec 30a does have a straight/level function and it works but I wouldn’t trust it past about 30 degrees of bank, however I haven’t tried it. When engaged with the trim set properly, it will reliably hold altitude. If the trim isn’t set properly (or you slow down/speed up), it will yell at you enough to get your attention before going off altitude. The gfc autopilots have a lot more functionality that makes them great for ifr (altitude selection, approach modes, climb type, etc), but my stec is very reliable for vfr and helps out reasonably in ifr. edit: this is from the gfc500 manual for a pa-28. Point is there are engagement limits in airspeed (high/low), bank and pitch. They are big, but I have personally seen someone try to recover an SR-20 from ~70 degree bank with the button and nothing happened. It took a couple seconds to realize and recover by hand which reinforced the need to practice handling recoveries manually.

Yeah, I wish the oat would populate from the jpi930 to the g5 as well but it doesn’t. My gps (430w) gets oat from the 930 for that tas/wind calc page, but the oat isn’t fed to the g5.

My edm 930 has temp and gets groundspeed from the gps, but it has no way to display tas or winds as it doesn’t have heading or ias. I have 2G5s, but do not have temp or winds on them. It is a pretty simple calculator on my Garmin 430 GPS to get that info, however.

I also wonder how sensitive it is to getting the pitch trim set very precisely for itself. Example (and yes, different system, but hear me out) - on my stec 30a, if I set alt hold in stable cruise and then slow down (or speed up) ~2 knots, the “trim”warning will not activate and the unit will be able to hold altitude, but it has a very similar oscillation to what you guys have shown as the pitch servo is “fighting” to hold altitude. If i make a very minor trim adjustment, it’s steady. Is the pitch trim on the gfc500 setting itself very precisely as airspeed or cg change or does it have a less precise adjustment schedule?

It climbs a bit better and you get a couple of knots more. At cruise power, you’ll only have ~7 more hp. Roughly. From the other folks on here, the change was noticeable mostly in climb. Less so in cruise. It’s a newer design and has all the improvements incorporated into the newer versions of the io-360.

Oh yeah, we’ve got some real winners too, I wasn’t trying to single out you guys! Honestly, I’ve had 99% simple and professional interactions up there. Actually, usually they don’t come out to the airplane. This one was just strange.

I have been to canada a few times recently and read that as well. I took it to mean that the GA and corporate air programs were not affected. I will say that i had my first negative experience going to canada and using our company Corporate Canpass. I’ve been doing it for a while and I follow the rules exactly as published on their website. When I arrived in Kelowna, I was ~10 minutes after my scheduled time and well within my 30 minute window. Iaw the corporate rules, we didn’t need to call, so we exited the airplane and headed to the fbo. About 15 minutes later, I walked out to supervise fueling and customs officers drove up. They weren’t pleased that I was outside the airplane. As politely as I could, I pointed out that I was on corporate canpass. No change in attitude. I pulled out the rules. The officer said, “The people running CANPASS are teenagers and don’t know what they’re doing. Get your passengers back here immediately.” Since he had the badge and gun, I complied by calling them and they drove back. They (but not me because I was “only the pilot”) were taken to the cbo office for about 15 minutes and then released. Funny, the next day I had to come back to pick up the pax. Paranoid, I sat in the airplane and called CANPASS (which you don’t have to do on corporate canpass). Officers (different ones) showed up while I was still on hold about 10 minutes later. I mentioned that I was on corporate canpass and they asked why I was calling and still in the airplane then?

Aeromoters rebuild is the usual (and good) solution.

@Davidg I was going to say, “they all do this” until i see you have a mechanical gage. @PT20J and I have fought this on and off for a while, but we’ve sort of concluded that it’s something to do with the electrical transducer and eis (he has a g3x and i have a jpi930). Mine has done this on and off for years. Occasionally I try to fight it with a snubber (which caused a self inflicted leak), new lines, tightened connections, etc. I’ve had it steady for about a year at most but it has always returned and I still haven’t nailed down what causes it. However, you would be the first one Ive heard of with a mechanical gage that’s showing the same thing…

I had my wife and two kids in the airplane on a long xc over eastern oregon when the twins were ~1. We changed my daughter’s dirty diaper across our lap in the front seat. Boy that airplane stunk! I thought long and hard about sliding that diaper out the window and depositing it in eastern oregon, but I was afraid it would hit the tail and explode all over the empennage which would have significantly reduced the cool factor of our arrival at my parents place. I think youd be safe out the door or window with tp though. If you use the door, don’t expect to close it in flight. It’s really tough to open more than 2” and tougher to close.

I have a surefly too, but it isn’t “free”. You’ll need to remove interior and run a power wire to the battery. You also might need a new harness to match the SF. That being said, I like mine. if you keep the mag, just do the exchange.

I’m betting it’s pretty simple. A loose or corroded connection between the power bus and avionics bus. You need to test several points along the line back from the avionics bus to find that big drop. Could be at the avionics master or at the connections to either bus or at the circuit breakers. 0.5v drop is pretty good resistance at one point! Also, only having the unnecessarily new vr is a win! I got new vr, alt and field wiring before finally doing this testing!

100% what eric just said. Test both sides of a breaker as the breaker could be bad. Additionally, it depends on where the jpi power is wired. The jpi comes on with the master, so it’s wired after your master solenoid (mine is right next to the battery). Some installs have a wire run from the solenoid to the jpi, so I’m just saying that it isn’t necessarily connected to the main bus, but that’s a reasonable place to check. You really want to check the install guide to give you an idea. Depending on what type jpi, it might have a fuse but no circuit breaker.

Eric, do you happen to know if there’s a separate “sense” wire to the jpi for voltage or is it displaying its own input voltage? It might help narrow down where the loss is?

One other thing that’s kind of coincidental… mine ended up very similar. Theres a thick jumper between the power bus and aux bus bar right near it. Mine had a bad connection on that big jumper, so I had 14v on one bus bar and 13v on the one next to it.

You still need to check the avionics bus and/or any other busses added over the years. I believe the jpi is not sensing it’s own input, but has a separate Sense wire connected somewhere else. Maybe someone else can confirm that or look through the jpi wire diagram from their website. you’ve narrowed it down for sure. Alt and vr are good.

I have a kelly on one side and maggie on the other. Both work. Id use maggie next time for price and easy to work with (ordering, customizing, etc).

Yes, I felt pretty stupid to when I realized mine was similar… 14v was coming through the firewall but the connection to the bus was bad. Seems easy looking back. Trace that 13v back to where it connects to 14v bus and you’ll find the issue.

I went in circles for 2 years. It’s a process. Make sure you’re getting 14v out of your alternator, then at least you know the alternator and vr are ok. Good luck!

Just to be clear for the OP though, the airplane will (should) keep the constant 14v you mentioned, not the lower float charge.

I think you’ve got an issue to find. You should see constant 14v +/- 0.1 or so. The Zeftronics Troubleshooting guide is good, but I followed the voltage out of the alternator with my engine running to find my issue.

Yes, I did do that. Both the Zeftronics and plane power sites have troubleshooting guides that lead you through pretty well. You won’t have the full battery voltage on the field wire, but close. The zef troubleshooting guide gives you a range (~11.5-11.8) or so. Heres what I found… it’s relatively easy to find very small losses with just battery voltage and no draw. You can spin your wheels (and I did) finding inconsequential losses. A EE buddy of mine finally suggested following the voltage out of the alternator with the engine running. V=i x r, so you see a bigger voltage drop across the same resistance with higher current. It was pretty clear where the problem was and was not when I tried it this way (with avionics and lights on supplying draw). I dont mean to say there are a few checks that are good to try first. Definitely check the field voltage at the alternator (and the connections there). Check the bus voltage at the cigar lighter to see if it matches your other low indication. I might also try (because it’s easy) testing battery voltage and following that through the starter solenoid and to the bus, but remember that the alternator voltage is following that route TO your battery, not to the bus, so it’s more likely the problem is between the alternator and the bus if the bus is low.

If you crank it up and see 14v measured at the alternator, and less than 14v elsewhere, then the alternator isn’t your problem. Be careful near the prop.