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RV-10 N783V: My 1st Emergency

Autopilot Mode Reversion

Also thanks for this posting and thanks for Garmin for helping with the operation of the A/P. Seems logical that the A/P would disconnect but also seems logical that the A/P would help us "keep the shiny side up". Recently I lost GPS on the 750 and the A/P disconnected which at the time seemed logical but a little inconvenient as I was in the final stages of my approach. I always thought the A/P was just a luxury and hand flying the airplane is what I was trained to do but you know the drill. I guess I need to read the operating manual more carefully but it is long....... I have to admit I would have been a little more than tense under those conditions when all of a sudden the A/P turns into my enemy. For me I knew all I had to do was a few minutes of "aviating" but for this person he had a very uncertain time period to endure. Hats off for staying cool, flying the airframe and documenting the training video for us all to learn !!

Good Morning,

We are happy to help work through these events, to help better understand how the system handles an unexpected flight condition. In these cases it is often helpful to review the flight data logs generated from the flight to understand the series of events leading up to the failure, as we keep a detailed account of Autopilot commands and active modes, among many other items, in the 1 Hz datalogs. We are always happy to review the logs with you if you send them over to us at [email protected].

Thanks,

Justin
 
Stein did it!

Can’t you share how you did this? I’m interested in adding it to mine.

I used Stein for my panel so they programmed the alert. I have a Gap-20 pitot. Perhaps G3xpert could chime in on how to make it happen. I believe it has to do with programming discreets.
 
Hello,

Revision AM of the G3X Touch Installation Manual, Section 35.4.32.26.1, details the GAP 26 Alert Configurations. This is available for the -20 version (Heated/Regulated) only, due to being equipped with a discrete output.

The discrete output from the heat control box of the GAP26 -20 version will be connected to one of the EIS (GEA) discrete input pins. There are 3 recommended ways to configure the alerts:

1. 'Pitot Heat' indication in Green on the PFD when the probe is powered on and probe temperature is above 25 degrees Celsius (77 Fahrenheit). (On and Operating)

2. 'Pitot Temp' indication in Yellow on the PFD when the probe is powered off, or is powered on and the probe temperature is below 25 degrees Celsius (77 Fahrenheit). (On or Off, Not Operating)

3. 'Pitot Temp' indication in Yellow on the PFD when the probe is powered off, or is powered on and the probe temperature is below 25 degrees Celsius (77 Fahrenheit), with additional logic that will not display when flying in an OAT above 7 degrees Celsius (45 Fahrenheit). This configuration is depicted by Figure 35.53 (Configuration #3) on page 35-186. (On or Off, Not Operating, display only when OAT below 45F)

So, option 3 would be a desired option to provide a Yellow 'Pitot Temp' CAS message on the PFD if you are flying in temperatures below 45F and your probe is not being powered/heated.

BR,

Brad
 
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Alert below freezing and pitot off

Some of us were concerned about "noise" issues coming from the regulated heating system and went with the pitot heat on/off system. Any way we can get a warning when OAT drops below ? F and/or we have not turned on the pitot heat? (My car gives me a warning when OAT drops below 35 F)
 
Is there a concern about having the pitot heat on all the time? It isn't necessary, but if it doesn't hurt anything either, why not? Better than forgetting it the one time it is needed.
 
Thanks!!

Randy

Thanks for sharing this. I learned a lot, great job on getting back on the ground safely. I have been in a few tense moments in my flying am amazed at how easy it was for me to concentrate on the wrong thing and how long (minutes) it took to figure out just to fly the plane.

I have had my ELT activate in flight and break squelch and swamp my radios, that constant noise\alarm is so very distracting.

Thanks again



Steve
 
Is there a concern about having the pitot heat on all the time? It isn't necessary, but if it doesn't hurt anything either, why not? Better than forgetting it the one time it is needed.

If you have one of the temperature-regulated pitots, I’d say leave it on, with the possible exception of cold wx starts, when you might not want any excess current draw. These things draw about 10 amps when full on, so electrical load needs to be considered. For the non-regulated pitots, I’d try to turn them off when not needed. Since they run full-on, most of the time they will be hotter than needed. First time you land with it still on, go to tie down, brush the pitot with your hand and burn your skin off, you won’t ever forget.
 
Sorry, I should clarify. I didn't mean literally all the time, 24/7, only when airborne. Turn it on before take-off and turn it off after landing. That way there's airflow to keep it from overheating. In my day job, pitot heat comes on after engine start and off after landing.
 
At the risk of drifting off topic I am curious how many pilots get trained how to land without a functioning airspeed indicator? I was fortunate to have an old school instructor who taught me. The 2 things that surprised me were how easy it is to do consistently and safely and that my landings tended to be better when I didn’t look at the airspeed. You fly using the sight picture of the runway in the windscreen, which gives you the correct pitch, and you make sure the runway isn’t moving up or down in the windscreen, which gives you the right glideslope. If both of these are right, then AOA is right, which means the speed us right. When I practiced this with my instructor he would put a cover on the ASI and pull it off right before flare in the speed would be bang on. I landed better because I was more focused on getting the attitude and glide slope jyst right, constantly adjusting pitch and power. I had to master it before he let me solo. Of course this is strictly vfr. It doesn’t work if your wind screen is full of cloud.

He also taught me that when stuff goes wrong, your brain shrinks. Looks like that’s what happened here. The pilot is not an idiot, he is a human bean. I’m sure we’ve all been there. When you get there and if you recognize it you have load shed and focus on nothing but flying. Most accidents are caused by distraction, and probably in a lot of cases stress plays a part.
 
Sorry, I should clarify. I didn't mean literally all the time, 24/7, only when airborne. Turn it on before take-off and turn it off after landing. That way there's airflow to keep it from overheating. In my day job, pitot heat comes on after engine start and off after landing.

Little airplanes have little power supplies (alternators), I always hate to waste energy unnecessarily so having pitot heat on all the time is wasting 7-8 amps avg. just seems wasteful and makes the alt work that much harder.

Just remember to turn it on when in freezing temps in the clouds, which for me is almost never (live in TX).
I probably shouldn't be in those conditions in the first place.
 
Randy,
The line in the video that caught my attention was: I am IFR Rated. You are most likely able to tell your story because of that. Thanks for posting.

As I watched the clouds get thicker and thicker, it was very uncomfortable watching. Im glad I knew the end of the story!
 
Little airplanes have little power supplies (alternators), I always hate to waste energy unnecessarily so having pitot heat on all the time is wasting 7-8 amps avg. just seems wasteful and makes the alt work that much harder.

Just remember to turn it on when in freezing temps in the clouds, which for me is almost never (live in TX).
I probably shouldn't be in those conditions in the first place.

There-in lies the trick. Sometimes a person will forget to turn on the pitot heat in clouds. It's quite easy to forget when task saturated. That's part of the reason for this thread's existence. Is it worth the extra 8 amps on an alternator for the rare situation like being discussed in this thread? I suppose that's a question each pilot will have to decide for themselves based on how and where they operate their aircraft.
 
...Although I love the looks of the panel I think it offers a good lesson on panel ergonomics as well, constantly leaning over to set up the GTN looked like a real problem, doing that with no AP is always going to put you in a bank. A couple of times there it looked the bank angle was quite steep, almost the beginning of a spiral. Looked scary...

I'd like to hear the OP's thoughts regarding this point? Hindsight is 20/20. So now that you've been in the hot seat, how do you feel about the placement of the GTN-650 on the right side of the panel? Did you find the reach to be cumbersome, difficult, distracting, awkward, etc?

Given your recent experience, would you place the GTN in the same position if designing another panel?

When designing a two screen panel, there seems to be a tradeoff in choosing screen positions. In biasing both screens toward the left seat, the obvious benefit is situating more displayed information nearest the pilot who, in most cases, will be manipulating the controls. This comes at the expense of less information in front of a right seat pilot and seemingly at the expense of creating a further reach to the stack.

Conversely, a center mounted stack is seemingly more easily manipulated by the left seat pilot and is just as easily manipulated by a right seat pilot. And placing the second screen on the right gives a right seat pilot a full compliment of information in direct view. This configuration seemingly renders the information displayed on the second screen less useful to a left seat pilot.

Everything is a compromise and everyone has a preference. But real world experience proves more useful than creating a spreadsheet listing perceived pros vs. cons.
 
I'd like to hear the OP's thoughts regarding this point? Hindsight is 20/20. So now that you've been in the hot seat, how do you feel about the placement of the GTN-650 on the right side of the panel? Did you find the reach to be cumbersome, difficult, distracting, awkward, etc?

Given your recent experience, would you place the GTN in the same position if designing another panel?

I always value Walt's opinions on this forum, and thought he was very observant for picking up on this point about the "reach" to the GTN.

I also agree that it's all about "trade-offs" when deciding layout. Having two screens on "my side" of the plane gives be MUCH better view of up to 4 screens at once (in split screen mode). I usually fly with at least 3 of the possible 4 showing at all times. This really helps my situational awareness. The GTN is slightly farther away, yes, but manageable (I have long reach). I'm not usually flying with another pilot right seat, and when I do, they are often CFI's that are used to looking at the other side for info (think C172 panels in training aircraft).

So, with 20/20 hindsight, I would keep the two screens together on pilot side for pilot's benefit. But, because of my panel layout, I have a totally empty spot in the middle just above my fuel selector (see pic of panel) where it could have gone. I think GTN there would have had better placement there.

If I didn't have that spot to put GTN, and I had to choose only between 1 left screen, or a farther reach to GTN, I'd stay with the 2 screens on one side like I have it.

Part of the struggle Walt is witnessing, is not related to reach as much as it is eroded competency from being behind the airplane and the turbulence that is not as noticable with the stabilizing feature of the camera. (Touch screens in turbulence are hard no matter where they are.) Flew GNS530 for years. GNS navigators MADE you select an initial approach fix. The GTN defaults to "vectors to final". In the middle of the chaos, I didn't "pick" the IAF, so it defaulted to vectors to final if you don't make another IAF choice. Then I had to redo. All stressful in that situation. Had the GTN been closer, MAYBE it would have helped???? (but I'm not sure).
 

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I always value Walt's opinions on this forum, and thought he was very observant for picking up on this point about the "reach" to the GTN.

I also agree that it's all about "trade-offs" when deciding layout. Having two screens on "my side" of the plane gives be MUCH better view of up to 4 screens at once (in split screen mode). I usually fly with at least 3 of the possible 4 showing at all times. This really helps my situational awareness. The GTN is slightly farther away, yes, but manageable (I have long reach). I'm not usually flying with another pilot right seat, and when I do, they are often CFI's that are used to looking at the other side for info (think C172 panels in training aircraft).

So, with 20/20 hindsight, I would keep the two screens together on pilot side for pilot's benefit. But, because of my panel layout, I have a totally empty spot in the middle just above my fuel selector (see pic of panel) where it could have gone. I think GTN there would have had better placement there.

If I didn't have that spot to put GTN, and I had to choose only between 1 left screen, or a farther reach to GTN, I'd stay with the 2 screens on one side like I have it.

Part of the struggle Walt is witnessing, is not related to reach as much as it is eroded competency from being behind the airplane and the turbulence that is not as noticable with the stabilizing feature of the camera. (Touch screens in turbulence are hard no matter where they are.) Flew GNS530 for years. GNS navigators MADE you select an initial approach fix. The GTN defaults to "vectors to final". In the middle of the chaos, I didn't "pick" the IAF, so it defaulted to vectors to final if you don't make another IAF choice. Then I had to redo. All stressful in that situation. Had the GTN been closer, MAYBE it would have helped???? (but I'm not sure).
Thanks for the thoughtful feedback.
 
For those still building, I would recommend if possible, to consider keeping your AP and GPS together. I have a Garmin 307 center stacked on top of my 650. I operate it like it’s a FMS. Everything is right there, so you have minimal distraction and hand movement when things get busy. In this video you can see the back and forth between the AP and GPS. If your IFR your eyes will be following your hand from the screen to the AP, to the GPS and back around. Having a center screen is nice, but the second screen is a convenience since all display information is always available anytime on the pilot screen. Having the AP and GPS in the center stack and next to the pilots screen minimizes both hand and scan movement. This makes a difference when the cockpit gets busy. But I know every builder has their own vision of what works for them and that’s understandable.
 
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Little airplanes have little power supplies (alternators), I always hate to waste energy unnecessarily so having pitot heat on all the time is wasting 7-8 amps avg. just seems wasteful and makes the alt work that much harder.

Just remember to turn it on when in freezing temps in the clouds, which for me is almost never (live in TX).
I probably shouldn't be in those conditions in the first place.

This is why they make a regulated version of the pitot heat... so its not on when its not needed
 
Can the EFIS systems, Garmin, Dynon, GRT Etc. create a caution when the OAT drops below 10c by chance? This way if you don't want to run your pitot heat you can get a heads up that your in temps that can cause icing. I believe most airlines and military use 10 Celsius vs. zero as the anti ice turn on point.
 
What I was trying to get at was for folks that don't have Anti Ice but do have Pitot heat they could use the 10 Celsius rule of thumb like the airlines do for anti ice if they don't want to keep it on all the time, and if the glass avionics offer a warning option for temperature.
 
Understand

I understand; my point was that the airlines use the pitot heat all the time. In this case, using the pitot heat would have prevented the OPs issue, completely.

I equipped my -10 with the regulated pitot...it gets turned on after start and turned off at shutdown. Barring a mechanical failure, the Issue the OP had should never happen...
 
Update on a another "lesson learned" since this incident occurred.....

The AP did NOT disengage when airspeed went to zero due to ice! I disengaged it manually.

Here's what happened (and I think it's good for all of us to know) the Garmin AP has a safety feature programed so if it sees airspeed dropping to stall speed, the servos will ease the nose over to avoid an anticipated stall. This feature goes away when air speed hits 30 KIAS. When my airspeed was dropping, AP was pitching nose down. When KIAS dropped below 30, I felt a sudden and strong pitch up (at same time stall warning goes off). My perception was that this was AP disengaging due to no airspeed. It was not. So, when I grabbed control stick, I was not concerned about hitting disconnect switch, which I did.

Bottom line, Garmin AP will work without any indicated airspeed! (Think ground checks.) I could have hit the Blue level button in this situation, but I didn't think it was working without airspeed. It was! Hopefully, this is another lesson for others that can save a life down the road.

Garmin is looking at some changes that may help others in my situation down the road. Thank you Garmin for using this to help us all. GREAT customer service!
 
To clarify the previous comments about ice protection, pitot and static heat is on whenever airborne. It's the other ice protection systems (props, wings, windshield, engine intakes, etc.) that are turned on at +5*c or +10*c prior to, or after entry into visible moisture. All depends on the system, conditions, aircraft and company.
 
Randy,
Thank you for posting this. You were really lucky as you already know. Your attitude toward learning and teaching is commendable and should be praised greatly.

As a Commercial pilot that has flown most of my entire career single pilot, I can say one thing for certain. Your skills saved your life. You struggled, but you ultimately won.

That said, I hate when the conversation revolves around technology and auto pilot safety. Your video shows exactly what happens when technology fails and a pilot is too reliant upon it for success. Technology literally can "fail" because we "disengaged" it ourselves. In fact, as you know, you were on the verge of failing more technology by randomly pulling circuit breakers.

Again, you did an amazing job. Be proud that you saved your life.

I hope people can see that more technology in their aircraft is not neccisarily the answer to increased safety. But that solid proficient skills will always trump technology.

Thanks for sharing
 
Another Thanks To OP and Follow Up Question

Update on a another "lesson learned" since this incident occurred.....

The AP did NOT disengage when airspeed went to zero due to ice! I disengaged it manually.

Here's what happened (and I think it's good for all of us to know) the Garmin AP has a safety feature programed so if it sees airspeed dropping to stall speed, the servos will ease the nose over to avoid an anticipated stall. This feature goes away when air speed hits 30 KIAS. When my airspeed was dropping, AP was pitching nose down. When KIAS dropped below 30, I felt a sudden and strong pitch up (at same time stall warning goes off). My perception was that this was AP disengaging due to no airspeed. It was not. So, when I grabbed control stick, I was not concerned about hitting disconnect switch, which I did.

Bottom line, Garmin AP will work without any indicated airspeed! (Think ground checks.) I could have hit the Blue level button in this situation, but I didn't think it was working without airspeed. It was! Hopefully, this is another lesson for others that can save a life down the road.

Garmin is looking at some changes that may help others in my situation down the road. Thank you Garmin for using this to help us all. GREAT customer service!

Many thanks for following up on the autopilot disconnect aspect. I am currently installing and wiring an almost identical dual G3X system, albeit in my RV-7 project, so this has been of interest.

Modern autoflight systems are complex enough that those like me who come from an airline or other professional flying background would probably agree that they have more than once heard or made the comment “why’d it do that?” on flight decks at work when the autopilot was engaged.

And the modern glass that we put in our little airplanes is every bit as full featured as those in modern heavy metal.

There is one question for the OP that is not clear to me at least. Did you hit the CWS (autopilot disconnect for those not familiar with Garmin-speak) button on purpose, or was it inadvertently pressed when placing your palm on the stick during that moment of stress, turbulence and high workload?

For those still in the decision making phase on stick button ergonomics, does placement of the autopilot CWS/disconnect button on the front of the stick right underneath where the palm normally rests create an increased susceptibility of inadvertent actuation?
 
Randy,

I want to join others in thanking you for bravely sharing your experience and your video. Most of us will never experience an iced up pitot probe, but watching your airspeed go from normal to zero in a few seconds was quite eye opening! Good job keeping the plane upright while you sorted things out and got the pitot heat going!

You invested wisely in your avionics. It is probably safe to say that most, if not all, modern ADAHRS units use airspeed in their attitude calculation algorithms, and the fact that your two independent, dissimilar, G5 and GSU 25 ADAHRS units were able to immediately recognize the loss of valid airspeed data (without any airspeed sensor failure in either unit) and adapt their calculations to use the remaining air and GPS data to keep your attitude indications rock solid and continue to support the pilot and autopilot is impressive.

Similarly, when you turned pitot heat on, your pitot thawed out, and your airspeed jumped from zero to normal speed in a few seconds, both of your ADAHRS units were again rock solid and were not negatively affected.

I have this equipment in my plane, and am glad to see that if I were to suffer a similar iced up pitot situation, the G5 and GSU 25 would continue to reliably provide altitude, pitch, roll, and yaw.

Bottom line, Garmin AP will work without any indicated airspeed! (Think ground checks.) I could have hit the Blue level button in this situation, but I didn't think it was working without airspeed. It was! Hopefully, this is another lesson for others that can save a life down the road.

The blue level button has been mentioned a couple of times in this thread, and I want to point out that using this button is entirely optional and not at all necessary, under any condition, to re-engage your autopilot.

Your autopilot was manually disengaged, but the flight director (autopilot modes) was still setup, and all that was necessary to restore the autopilot was to reach up and press the AP button in the center of the control panel.

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Even though you temporarily lost the use of IAS (airspeed hold) mode on your G3X Touch autopilot until your pitot probe thawed out, all of the other modes were fully operational and available to you.

One other comment is in regards to your AOA audio volume. The AOA tones volume level is independently adjustable from the Sound configuration page in your G3X Touch system. You might want to consider turning it down a bit. Personally, I have mine set rather low. It just loud enough to be a gentle reminder to me, but not so loud that it disturbs passengers or would be much of a distraction if it were on full time like yours was. Of course, turning off the audio panel while still retaining COM1 capability is another option to remove the distraction.

Thanks,
Steve
 
There is one question for the OP that is not clear to me at least. Did you hit the CWS (autopilot disconnect for those not familiar with Garmin-speak) button on purpose, or was it inadvertently pressed when placing your palm on the stick during that moment of stress, turbulence and high workload?

The short answer is, it was inadvertent.

I was convinced the AP had already disconnected itself, so in that moment, I wasn't concerned about hitting the AP disconnect button on my stick, nor was I trying to on purpose. Usually, I'm very aware of the disconnect button and always have a "light touch" on the stick to I won't disengage it with a strong grip. In this moment, I didn't care about a strong grip or the inadvertent disconnect of something I believed to be already "disconnected".

The Garmin data logs are VERY detailed. They showed it was a "manual disconnect", meaning, I hit the button. I was not trying to, nor was I trying not to, it just happened in the stress of everything else.

Hope this gives clarity to your question.
 
Another future configuration option that would be nice for these Glass systems is a audio alert when the autopilot kicks off on its own and a similar but different tone when its kicked off manually. For example a "Autopilot autopilot" for inadvertent disconnect. TACK TACK sound for manual disconnect.
 
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