G5 installtion progress [[Previously: Opinions on my panel]]

[denverpilot]

With a Century ya just turn the knob thing on the DG or HSI to move the heading bug. No need to turn it off then on. Told ya’ll head be disoriented.

(Never ever notice attire, piercings, skin art, or hair in Boulder. Never)

LOL. He said CHEAP Autopilot. Mine does “heading” by making sure the Turn Coordinator doesn’t flop left or right. No heading bug.

I don’t know what AP he has, but I bet what Heading mode does is written in that manual that came with it that has to be aboard for the airplane to be airworthy. Just a guess, mind you.

 

[denverpilot]

P.S. Some of the “art” was kinda cool. I was more interested in how Apple found ALL of the people who both knew how to fix a Mac, AND had such “art”. Hahahahaha.

 

[Clark1961]

LOL. He said CHEAP Autopilot. Mine does “heading” by making sure the Turn Coordinator doesn’t flop left or right. No heading bug.

I don’t know what AP he has, but I bet what Heading mode does is written in that manual that came with it that has to be aboard for the airplane to be airworthy. Just a guess, mind you.

Your ‘Autopilot’ is more of an auto-wander.

His is a Century 2000 which is a pretty nice AP and definitely not cheap.

 

[denverpilot]

Your ‘Autopilot’ is more of an auto-wander.

His is a Century 2000 which is a pretty nice AP and definitely not cheap.

Okay. I’ve always known my AP doesn’t measure up.

It usually needs a big ol’ dunce cap after I tell it to go sit in the corner and think about what it did.

 

[arkvet]

RE G5 HSI to AP interface:

It will take some getting used to putting the AP in heading mode to fly gpss. seems counterintuitive that for all this time I was hitting Nav then App on the century 41 to keep the AP happy. Now, from what I understand I simply leave the AP on hdg mode all the time and simply toggle gpss on/off. When it’s off the AP is in hdg mode.

I only have one brief flight with G5 HSI so far but that’s how it appeared and that’s how the manual reads. I’m coming to accept the fact that the Nav and App buttons on the AP will never have to be touched again.

 

[Clark1961]

RE G5 HSI to AP interface:

It will take some getting used to putting the AP in heading mode to fly gpss. seems counterintuitive that for all this time I was hitting Nav then App on the century 41 to keep the AP happy. Now, from what I understand I simply leave the AP on hdg mode all the time and simply toggle gpss on/off. When it’s off the AP is in hdg mode.

I only have one brief flight with G5 HSI so far but that’s how it appeared and that’s how the manual reads. I’m coming to accept the fact that the Nav and App buttons on the AP will never have to be touched again.

As long as it’s an RNAV approach that is correct. If you choose to fly an ILS, LOC, or VOR approach then the normal buttonology is still used on the final approach segment where radio nav is used. If your GPS will give guidance on the final approach segment then GPSS could be used and radio nav monitored as primary guidance. I suspect the 41 will do fine on gps overlays. My system is set to switch to radio nav on an ILS and if glide slope coupling is desired then it’s gotta be manually set to LOC mode at least 10 seconds before the glideslope intercept.

In other words it’s complicated in explanation but not too bad in flight. I had to make a couple flights with instructors to really get it on all the sequencing for mixing gps and radio nav. On the other hand RNAVs are a breeze.

 

[denverpilot]

It will take some getting used to putting the AP in heading mode to fly gpss. seems counterintuitive that for all this time I was hitting Nav then App on the century 41 to keep the AP happy. Now, from what I understand I simply leave the AP on hdg mode all the time and simply toggle gpss on/off. When it’s off the AP is in hdg mode.

Anhhhh! I see now.

Yeah, think like a lazy engineer trying to avoid FAA certification headaches.

By simply driving a voltage into the heading bug input of the AP to “go left” or “go right”, which is all the heading bug does as the DG rotates... they avoided a lot of design and testing headaches.

 

[arkvet]

Ahh. Didn’t think about that Clark. I fly mostly smaller airports so RNAV are the vast majority of the approaches. Yes the gpss / should always provide magenta line guidance onto the final approach course... but if shooting a non gps approach that’s when I would need switch to App mode. Got it. Anxious to get out and test the buttonology.

 

[Clark1961]

Ahh. Didn’t think about that Clark. I fly mostly smaller airports so RNAV are the vast majority of the approaches. Yes the gpss / should always provide magenta line guidance onto the final approach course... but if shooting a non gps approach that’s when I would need switch to App mode. Got it. Anxious to get out and test the buttonology.

Yeah, I got myself into a situation where I'd fly RNAVs using GPSS and radio nav approaches by hand because I didn't know how the system was going to act in transition from GPSS to radio nav...that and around Denver Approach can do funny things with us flibs. We aren't an annoyance to them (I think) but we aren't their focus in life either. They definitely don't default to giving us enough room to set up a coupled approach while the greater Boeing and Europeen aluminum people tubes are enjoying their 20 mile finals..

 

[arkvet]

My system is set to switch to radio nav on an ILS and if glide slope coupling is desired then it’s gotta be manually set to LOC mode at least 10 seconds before the glideslope intercept.

Not sure what GPS you're using. My IFD 550 will automatically switch to LOC / ILS if the criteria is met for the approach. Another thing I love about the IFD.

Crappy weather today and likely tomorrow. Weekend looks good for some PIREPS on the new panel setup!

 

[Clark1961]

Not sure what GPS you're using. My IFD 550 will automatically switch to LOC / ILS if the criteria is met for the approach. Another thing I love about the IFD.

Crappy weather today and likely tomorrow. Weekend looks good for some PIREPS on the new panel setup!

I’ve got a 430w and it will switch automagically to radio nav. The autopilot requires earlier switching and setup to couple on an ILS. The analog electrons aren’t happy like digital electrons can be...

 

[Stallhorn]

Thanks, I did not know that. Can you point me to any info on this issue?

Someone from the club called Garmin and were told that. Not sure where there would be any info other than calling Garmin. Maybe google might know something, but I haven't looked.

 

[Stallhorn]

When you say Master are you referring to the Red Master switch? The Red Master is the battery bus. My shop responded with "The STC installation manual states that the G5 system will be on the battery bus (listed as essential or main buss) not the Avionics bus". My airplane goes back to the shop on 2/28 to address the G5 failure and hopefully fix my HDG bug issue.

http://www.chiefaircraft.com/pdf/G5INSTALL.pdf section 4.3.2. Another plane of ours came backwith G5s wired to the avionics bus

 

[Baron62]

Not sure what GPS you're using. My IFD 550 will automatically switch to LOC / ILS if the criteria is met for the approach.

The GTN also transitions to Loc/ILS automatically when intercepted provided that the GTN is on VLOC/ILS mode. The Century NAV and APP modes should work like they did in the past for radio signal guidance.

On the century 21/31/41 AP you can also select HDG plus NAV when the navigator is in LOC/ILS mode and it should follow the HSI HDG bug until it intercepts the localizer and then folllow the localizer. I'm guessing it will do the same thing if the navigator is in GPS mode until auto transition to LOC/ILS even if in GPSS mode. Lots to test.

 

[flyingcheesehead]

All I was going to say about the AP thing is that no AP in heading mode does anything with WCA. It flies a heading you chose.

The only rule that is true of "all" or "no" autopilots in GA is that all of them work differently!

With an S-TEC, or the Century 41 that @arkvet has it sounds like, you put the autopilot in Heading mode when it's on GPSS and the GPSS converter takes over for the heading bug. The GPSS converter is like a navigator whose sole job is to manipulate the heading bug, but who is so good at it that he always chooses the perfect heading to maintain the course and the perfect timing to cause the plane to roll out on a new heading/course at the exact correct second when the course changes.

It will take some getting used to putting the AP in heading mode to fly gpss. seems counterintuitive that for all this time I was hitting Nav then App on the century 41 to keep the AP happy. Now, from what I understand I simply leave the AP on hdg mode all the time and simply toggle gpss on/off. When it’s off the AP is in hdg mode.

I only have one brief flight with G5 HSI so far but that’s how it appeared and that’s how the manual reads. I’m coming to accept the fact that the Nav and App buttons on the AP will never have to be touched again.

If you're navigating via GPS and steering via GPSS, this is true. If you're navigating a radio signal, you'll still use the others - Flying an ILS, for example. In practice, generally you'll be on HDG/GPSS on until talking with approach at your destination, whereupon you'll end up on vectors and have HDG mode selected but GPSS off, and eventually when you're on the last vector to intercept the approach you'll arm NAV/APPR mode. But check your manual! Like I said, they all work differently and I've never flown with the C41 so don't know its particular quirks.

 

[arkvet]

I’ve read my century 41 manual and understand what it reads. My issue (along with everyone else’s I’m sure) is that this AP was made before gps, RNAV and LPV existed so the manual is somewhat lacking in instructions in that dept.

I’m anxious to see if RNAV or LPV approaches couple with the glideslope and allow the AP to fly vertical guidance as well. I know it will for ILS / LOC.

 

[Clark1961]

I’ve read my century 41 manual and understand what it reads. My issue (along with everyone else’s I’m sure) is that this AP was made before gps, RNAV and LPV existed so the manual is somewhat lacking in instructions in that dept.

I’m anxious to see if RNAV or LPV approaches couple with the glideslope and allow the AP to fly vertical guidance as well. I know it will for ILS / LOC.

I suspect it won’t couple the glideslope without being in LOC mode but I’ve never flown a 41. Not even sure the G5 will output a glideslope error signal for LPV or LNAV/VNAV.

 

[bnt83]

It's seems pretty obvious just by looking at the wiring diagrams that the G5 and GAD29B have nothing to to with supplying vertical error to an autopilot. If your autopilot coupled in an approach mode before, then G5 installation shouldn't affect that.

 

[iamtheari]

question for people flying with ancient AP. this is the first time I noticed that when flying on Heading Mode on the AP, I set a heading and the actual heading G5 shows is 2-3 degrees off, it seems like its not correcting for WCA. with the old gyro its impossible to notice such deviations. thoughts?

I see that others explained that this is normal. I didn't see anyone saying why. When ATC tells you to "fly heading X," they mean heading literally. So if you are told to fly a heading but you correct for a strong wind, you will not be going the direction ATC expects you to go. Autopilots are designed around that idea. That, and the fact that until fairly recently they had no way of knowing your actual ground track unless it was along a VOR radial or localizer beam, so they had no way to determine a wind correction.

 

[drotto]

I see that others explained that this is normal. I didn't see anyone saying why. When ATC tells you to "fly heading X," they mean heading literally. So if you are told to fly a heading but you correct for a strong wind, you will not be going the direction ATC expects you to go. Autopilots are designed around that idea. That, and the fact that until fairly recently they had no way of knowing your actual ground track unless it was along a VOR radial or localizer beam, so they had no way to determine a wind correction.

I fly with a G500 hooked up to a King 150 autopilot. Even in heading mode the G500 seems to correct for crosswind and tells the AP to crab for wind correction. I am assuming the G500 even if it not technically in GPS mode is using ground track for the heading.

Sent from my SM-G950U using Tapatalk

 

[WannFly]

ok let me clarify, this wasn't a difference between Heading and Track. this 2 or 3 degree off was between where I kept the heading bug (on AP) and the actual heading that's coming from the Magnetometer. no 18 and 20 in the pic below. now, in traditional Gyro you wont be able to see a 2 degree difference. the way I think this *should* work is, I set the heading bug, G5 sends that to the AP, if G5 detects the actual heading is 4 degrees left, it should send another correction to the AP OR my understanding of this system is completely out of whack (which is most likely the case).

I will play more with this set up and report back on what I find.

 

[flyingcheesehead]

ok let me clarify, this wasn't a difference between Heading and Track. this 2 or 3 degree off was between where I kept the heading bug (on AP) and the actual heading that's coming from the Magnetometer. no 18 and 20 in the pic below. now, in traditional Gyro you wont be able to see a 2 degree difference. the way I think this *should* work is, I set the heading bug, G5 sends that to the AP, if G5 detects the actual heading is 4 degrees left, it should send another correction to the AP OR my understanding of this system is completely out of whack (which is most likely the case).

I will play more with this set up and report back on what I find.

View attachment 60566

I'm guessing that (for example) the autopilot always flies 2-3 degrees on the same side of the bug? IE, you set 000 as the heading and it flies 358, you set 090 and it flies 088, etc... In that case, you just need to have the avionics shop make an adjustment. You've gotta remember, the autopilot is interpreting the heading as a very small voltage being fed to it from the GAD29B rather than a digital heading, so they essentially need to reset the neutral point there and you'll be good.

 

[flyingcheesehead]

I fly with a G500 hooked up to a King 150 autopilot. Even in heading mode the G500 seems to correct for crosswind and tells the AP to crab for wind correction. I am assuming the G500 even if it not technically in GPS mode is using ground track for the heading.

Do you have GPSS on? If so, you're not really in heading mode even though the autopilot is set to HDG, and the GPS will be correcting ground track. If GPSS is off, it should follow the bug. If it's not quite on the bug, it's likely the same issue as in my previous reply, where an adjustment needs to be made.

 

[flyingcheesehead]

I’ve read my century 41 manual and understand what it reads. My issue (along with everyone else’s I’m sure) is that this AP was made before gps, RNAV and LPV existed so the manual is somewhat lacking in instructions in that dept.

I’m anxious to see if RNAV or LPV approaches couple with the glideslope and allow the AP to fly vertical guidance as well. I know it will for ILS / LOC.

It likely will fly RNAV/LPV just fine, if you put it into approach mode. Essentially, all the autopilot knows about is the needles, it has no idea where the needles are getting their information from.

There are very few autopilots today that were developed after GPS came about, with the exception of the Garmin stuff and all the others that just came out this year. That's why GPSS is generally a separate box from the rest of the autopilot, it's just faking a "bug" for the autopilot's heading mode. Things like LPV approaches still have your GPS creating an analog signal to send to your HSI or CDI, and that analog signal can still be fed to your autopilot, which has no idea that the signal is being generated by a computer (GPS) rather than a radio beam.

FWIW, I've never flown with an autopilot that can fly an ILS but can't fly an LPV... And that's exactly why, the autopilot can't tell the difference.

 

[WannFly]

I'm guessing that (for example) the autopilot always flies 2-3 degrees on the same side of the bug? IE, you set 000 as the heading and it flies 358, you set 090 and it flies 088, etc... In that case, you just need to have the avionics shop make an adjustment. You've gotta remember, the autopilot is interpreting the heading as a very small voltage being fed to it from the GAD29B rather than a digital heading, so they essentially need to reset the neutral point there and you'll be good.

that's an excellent point and I have had enough time with the system to figure that out. next time I fly, I will take a note.

 

[WannFly]

I'm guessing that (for example) the autopilot always flies 2-3 degrees on the same side of the bug? IE, you set 000 as the heading and it flies 358, you set 090 and it flies 088, etc... In that case, you just need to have the avionics shop make an adjustment. You've gotta remember, the autopilot is interpreting the heading as a very small voltage being fed to it from the GAD29B rather than a digital heading, so they essentially need to reset the neutral point there and you'll be good.

Spot on. Just flew for an hour and it’s always 3 to 4 degrees ahead of heading bug. I will talk to the avionics guy


Sent from my iPhone using Tapatalk

 

[WannFly]

Updat: went to the avionics shop, the avionics guys came onboard with 3 screwdrivers and started opening the AP while I am planning to take off. Gave him the WTF look, he said he is going to adjust the AP roll level( whatever that is) for next 20 ‘mins I flew around and he did something with the AP, the heading bug and the actual heading is now about 1 degree off at times. He said that’s the best these old AP will get close to a digital heading readout. So far it’s may be 1 degree off at times, most of the times it sticks to the digital read out.

Now, I might have to adjust the roll steering gain since it will fly a hold but won’t stay inside the hold. It eventually catches up magenta line, but the turns are taking me out of the holding pattern, which is cool in flat mid west, no so much in other places. I more trip to the avionics shop I guess


Sent from my iPhone using Tapatalk