Glass cockpit vs steam gauges

Not quite following. IFR cert every two years can cover everything IFR, be it digital or analog. Why would there be a second cert?
You do get one altimeter certificate for each altimeter. :dunno:

Yes, but not quite the same mental picture. And I'll often move the Bug to Minimums or Pattern Altitude quite a ways out. So this would be an always-there quick reference.
But if you already moved the bugs, how would the system know which altitude to be highlighting?

Also, I'm not sure I understand your description of what you want - Could you sketch it up? I'm curious!

I’m not familiar with your system, but it seems like there should be a better way to manage bugs.
Always bug the altitude you are cleared to climb/descend to right now, but don't change it more than the next altitude where you want to level off. Then, when you have a more advanced autopilot you'll already have the right habits and it won't kill you if you get distracted.
 
I’m not familiar with your system, but it seems like there should be a better way to manage bugs.
Bugs are Bugs.... YOU set them where you want for what you're doing in flight. So if you're using the Altitude Bug for something else, it does not show you that you've drifted a bit off Altitude because it may not even be in sight.

But the reason the old steam gauges were so much better in this regard is because it presented you with a "picture" of where the needles were pointing. And the mind will comprehend a picture MUCH quicker than it will text or digits. Something like 60,000 times faster. So if you learned in a glass cockpit, you may not realize the difference. And I'm not opposed to glass, just saying they could have incorporated some of the advantages of the steam gauges, while getting rid of all the down sides of the mechanical failures.
 
Bugs are Bugs.... YOU set them where you want for what you're doing in flight. So if you're using the Altitude Bug for something else, it does not show you that you've drifted a bit off Altitude because it may not even be in sight.

But the reason the old steam gauges were so much better in this regard is because it presented you with a "picture" of where the needles were pointing. And the mind will comprehend a picture MUCH quicker than it will text or digits. Something like 60,000 times faster. So if you learned in a glass cockpit, you may not realize the difference. And I'm not opposed to glass, just saying they could have incorporated some of the advantages of the steam gauges, while getting rid of all the down sides of the mechanical failures.
The "hundreds needle straight up and down" for cruise is definitely helpful, even in peripheral vision. That said, a massive 10" attitude indicator is also pretty obvious in peripheral vision, so I'd call it a wash. A 10"+ PFD with an analog altimeter next to it for backup gives you the best of both worlds.

I'm still curious what your vision is for the depiction. Sounds like it might be a really good idea, I just can't wrap my head around it based on your description.
 
Bugs are Bugs.... YOU set them where you want for what you're doing in flight. So if you're using the Altitude Bug for something else, it does not show you that you've drifted a bit off Altitude because it may not even be in sight.
So maybe you aren’t managing your bugs well.

Bugs are bugs, but automation management is a learned skill.
 
Except when they disagree by 40 feet.

That’s a somewhat easy one to solve for. Pick one as the primary and sync the second to it. I usually set my both to baro during preflight, verify the VSIs move when the alt static is engaged, and then see which altimeter matches (or is closest) to field elevation. 99 times out of a hundred, the G5 is closer than the analog is, so I sync the analog altimeter elevation to the G5 elevation.

The same ‘problem’ exists with the magnetometer-based heading indicator and the magnetic heading indicator (compass), yet few find issue with that.

If there’s one limitation I’ve found, it’s displays that don’t allow for a minimums (DA/DH) display. This seems to lead to many folks using the altitude bug as a minimums display, and that, to me, is what can really lead to some less than optimum usage of displays to enhance situational awareness.
 
I trained in 172's and two out of three were 'steam' gauges and one had a pair of G5's. No big deal moving back and forth amongst each plane. I then bought my own plane to finish training and put in a couple of GI275's and kept the other 4 instruments in the 6 pack. I found that I struggled with the ASI/VSI on the tape and found myself looking back and forth from the analog to digital gauges unless I covered up the analogs. Flash forward to my current plane which is all glass and within 10-15hrs of flight, I became completely comfortable with the all digital information. Necessity forced me into rapid acceptance and learning. Could I go jump in a 'steam gauge' plane (one that I have experience with) and be comfortable flying it? Sure thing, but I really love the presentation of the all glass panel.
 
And why is that, if they’re both coming from the same static system?
The electronic displays have the possibility of having a lot more adjustments made than an analog altimeter. In particular, the G5 can be calibrated separately at sea level, 10,000, 20,000, and 30,000 feet. There's no technical reason why they couldn't have it be every 1,000 feet, but that's probably overkill.
 
And why is that, if they’re both coming from the same static system?

Truthfully, I’ve never given it much thought. Probably a variety of reasons, to include granularity of displayable altitudes, solid state computing, vs the aneroid wafer and mechanical linkages, as well as the fact one altimeter is likely downstream of another in the static system.

There’s probably a more correct answer I need to learn, but right now I’m neck deep in learning GI275 PFD/CDI/EIS and GFC500 capabilities and operation.

We’re off to Bavaria for Christmas & Mew Year’s today so I’ll be spending any free time doing ground study until probably the middle of next month.
 
And why is that, if they’re both coming from the same static system?
The G5 doesn't have to deal with internal frictions and wear that an analog altimeter does. Plus the G5 as built in error compensation abilities vs a +/- tolerance range applicable to analog devices.
 
Truthfully, I’ve never given it much thought.
Truthfully, that’s the reason for my question. ;)

A lot of people just get it in their heads that “tech is better,” but don’t understand why it is (or maybe isn’t), what potential failure modes it adds, and how those failure modes would manifest themselves.

It kind of goes back to the “how much systems knowledge do we need” thread.
 
Truthfully, that’s the reason for my question. ;)

A lot of people just get it in their heads that “tech is better,” but don’t understand why it is (or maybe isn’t), what potential failure modes it adds, and how those failure modes would manifest themselves.

It kind of goes back to the “how much systems knowledge do we need” thread.

So we had a weird issue right before our last .411 cert where ATC advised our reported altitude did not match what they were seeing via the transponder.

Being dual G5, the PIC (not me) reverted to HSI to PFD mode and noticed the two PFDs altitude tapes mismatched, with the reversionary display being correct. I don’t know what that PIC does with respect to syncing altimeters nor what the analog altimeter showed. IIRC, the difference was about 100’. During the static cert, a small leak was found and corrected.

Since then I’ve tried to include a PFD to PFD crosscheck in my preflight.
 
So we had a weird issue right before our last .411 cert where ATC advised our reported altitude did not match what they were seeing via the transponder.

Being dual G5, the PIC (not me) reverted to HSI to PFD mode and noticed the two PFDs altitude tapes mismatched, with the reversionary display being correct. I don’t know what that PIC does with respect to syncing altimeters nor what the analog altimeter showed. IIRC, the difference was about 100’. During the static cert, a small leak was found and corrected.

Since then I’ve tried to include a PFD to PFD crosscheck in my preflight.
The kind of questions that come to my mind are, how did he determine that the reversionary display was correct, and would this error have shown up on preflight?

Pitot/static malfunctions seem to create a lot of confusion before they’re correctly resolved.
 
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The kind of questions that come to my mind are, how did he determine that the reversionary display was correct, and would this error have shown up on preflight?

Pitot/static malfunctions seem to create a lot of confusion before they’re correctly resolved.

My understanding is ATC said “We show you at x100 feet, what do you show?” His response was x,000 feet. Recycled transponder and got the same.

Reverted the bottom G5 to PFD and it showed x,000 feet, matching what ATC showed.

I’m mot sure this the PFDs would mismatch on the ground unless there was a blockage somewhere after the split in the static system to feed the separate G5s. Even then, I’m not sure it would show up.
 
I'm still curious what your vision is for the depiction. Sounds like it might be a really good idea, I just can't wrap my head around it based on your description.
To be quite honest, I haven't really thought it all the way through since I'm not in any position to push it through. But in the simplest of terms I'd probably just put a visible circle around the Airspeed and Altitude tapes and have a Dot that moved around the circle. Again, the mind picks up "pictures" SO much faster. So in cruise the dot is at 2pm and I glance over and it's moved to 3pm, I'd notice that. I'd also possible notice it if it started to move in either direction.

So again, the purpose would be to create an image that the mind would embed. Then it is a very fast function of the brain to confirm or take note of a change in the location of the dot. And I'm saying "dot" because that is what is coming to mind right now. If I were to actually lay it out graphically, I might come up with a totally different idea. But again, you do NOT want to read numbers and then interpret them, which is what the mind does with all text. You want both the numbers for specifics and a pictorial representation for that quick confirmation glace.
 
My understanding is ATC said “We show you at x100 feet, what do you show?” His response was x,000 feet. Recycled transponder and got the same.

Reverted the bottom G5 to PFD and it showed x,000 feet, matching what ATC showed.

I’m mot sure this the PFDs would mismatch on the ground unless there was a blockage somewhere after the split in the static system to feed the separate G5s. Even then, I’m not sure it would show up.
So he didn’t pick the one that was “correct,” he picked the one that matched what he was sending to ATC.

Based on the fact that it was due to a leak, I’d assume the higher altimeter was actually The one that was more in error since the pressure in the cabin is generally slightly lower than static pressure…if you have an alternate static source, open it in flight and you’ll likely see a very similar change in altitude indication.

Also, based on a (large) static leak I had, it’s entirely possible that the leak could affect the encoder end of the system without affecting the primary altimeter at the other end.

Ultimately a 100 ft error isn’t significant operationally, but with a larger error it’s important to be able to troubleshoot effectively. It’s easy to fall into the trap that somehow ATC can be a tiebreaker, but they’re simply seeing a part of our system.

Following up on that, if you determined somehow that the encoder was wrong, do you know how to turn off your Mode C if ATC says to “stop altitude squawk”?

Quite the rabbit hole, isn’t it? ;)
 
Or it could have been a transponder altitude reporting issue which allows up to a 125 foot variance between what the altimeter reads and what ATC sees.
But since one of the altimeters matched the encoder and a leak was subsequently found, would that actually apply?

It does kind of surprise me that ATC was questioning a 100 ft difference, though.
 
Truthfully, that’s the reason for my question. ;)

A lot of people just get it in their heads that “tech is better,” but don’t understand why it is (or maybe isn’t), what potential failure modes it adds, and how those failure modes would manifest themselves.

It kind of goes back to the “how much systems knowledge do we need” thread.
Some here may know of a book titled Through the Overcast, by Assen Jordanoff, a comprehensive textbook about instrument flying written in the 1930s when practical IFR was a new thing. The author goes to considerable length explaining the mechanical functioning of flight instruments of the day which, for those of us flying “steam gages,” is still 100% relevant. What’s more, modern glass instrumentation still uses pressure sensed by a pitot/static system to derive altitude and airspeed information, even if the raw inputs are processed by an ADC.

Many of us instructed at schools that had a collection of retired instruments, each with a section of its case cutaway to allow us to see its mysterious inner workings. Those helped students grasp the reality that despite their exorbitant cost they were actually quite dumb, so using them effectively required pilots to be knowledgeable regarding their operating principles and limitations (and why a gentle tap on the glass is sometimes needed). I doubt any schools today have a cutaway G5—might as well be looking at a circuitboard removed from a video game—but at least it would be obvious that glass-tapping would result in nothing more than an annoying smudge.

Of course, you already know all this; but someone else may find it interesting.

BTW, Through the Overcast is worth reading for the illustrations alone.
 
Some here may know of a book titled Through the Overcast, by Assen Jordanoff, a comprehensive textbook about instrument flying written in the 1930s when practical IFR was a new thing. The author goes to considerable length explaining the mechanical functioning of flight instruments of the day which, for those of us flying “steam gages,” is still 100% relevant. What’s more, modern glass instrumentation still uses pressure sensed by a pitot/static system to derive altitude and airspeed information, even if the raw inputs are processed by an ADC.

Many of us instructed at schools that had a collection of retired instruments, each with a section of its case cutaway to allow us to see its mysterious inner workings. Those helped students grasp the reality that despite their exorbitant cost they were actually quite dumb, so using them effectively required pilots to be knowledgeable regarding their operating principles and limitations (and why a gentle tap on the glass is sometimes needed). I doubt any schools today have a cutaway G5—might as well be looking at a circuitboard removed from a video game—but at least it would be obvious that glass-tapping would result in nothing more than an annoying smudge.

Of course, you already know all this; but someone else may find it interesting.

BTW, Through the Overcast is worth reading for the illustrations alone.
Wasn’t it taught in a non instrument plane caught above a solid layer to put the plane in a spin then recover breaking out the bottom preferably before hitting the ground?
 
Wasn’t it taught in a non instrument plane caught above a solid layer to put the plane in a spin then recover breaking out the bottom preferably before hitting the ground?
Yes, as well as instrument-capable planes with non-instrument rated pilots. I used to work with a guy who was a military pilot before and through WWII. he said even in B-17s they were told to spin down if they weren’t rated (which most weren’t prior to WWII.)

Probably more relevant today (although becoming less so with people removing turn coordinators in favor of an additional ADI) is the technique that the U of Illinois came up with in conjunction with AOPA back in the 50s…

 
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But since one of the altimeters matched the encoder and a leak was subsequently found, would that actually apply?
The 125 variance is part of the 2 year Part 43 inspection and measured on the output side of the xspndr in close proximity to the aircraft. I merely posted it for your rabbit hole journey. Operationally, all you can do is follow your AFM/POH limits, etc. But I have seen aircraft that were pegged by ATC on their altitude reporting only to find the reporting systems was within spec. As to the ATC reporting the 100ft, I've found with the prevalence of more aircraft with ADC based equipment there seems to be less acceptance of those type variances. It can especially sting if an owner has legacy equipment installed and he paid me easy money to tell him his aircraft is good.
 
Some here may know of a book titled Through the Overcast, by Assen Jordanoff, a comprehensive textbook about instrument flying written in the 1930s when practical IFR was a new thing. The author goes to considerable length explaining the mechanical functioning of flight instruments of the day which, for those of us flying “steam gages,” is still 100% relevant. What’s more, modern glass instrumentation still uses pressure sensed by a pitot/static system to derive altitude and airspeed information, even if the raw inputs are processed by an ADC.

Many of us instructed at schools that had a collection of retired instruments, each with a section of its case cutaway to allow us to see its mysterious inner workings. Those helped students grasp the reality that despite their exorbitant cost they were actually quite dumb, so using them effectively required pilots to be knowledgeable regarding their operating principles and limitations (and why a gentle tap on the glass is sometimes needed). I doubt any schools today have a cutaway G5—might as well be looking at a circuitboard removed from a video game—but at least it would be obvious that glass-tapping would result in nothing more than an annoying smudge.

Of course, you already know all this; but someone else may find it interesting.

BTW, Through the Overcast is worth reading for the illustrations alone.
The book is available for free on archive.org btw.

The Instrument Flying Handbook used to have better descriptions of the instruments and their operation as well.
 
Even basic EFIS (I have dual G5s) are a huge upgrade over the old analog gauges. Everything is right in front of you, including CDI information. The HSI self-corrects for drift using an external magnetometer, and I don't miss the vacuum system and random vacuum or vacuum instrument failures. I learned IFR on analog instruments, but the adjustment to EFIS was relatively easy. I still think it takes more brain power to interpret a speed tape compared to the analog dial, but I'm at peace with it for now. The altimeter tape is similar, but somehow not as problematic. But for IFR EFIS is a game-changer. It's almost like cheating. The one thing I notice most is how accurate the electronic AI is at displaying attitude. It's slightly different for every airspeed and loading for various flight regimes, but on the other hand very easy to set exactly the right attitude and power setting for precise IFR configuration.
 
I've owned my RV-9A for a little over six years and have put about 650 hours on it. It had steam gauges plus an IFR GPS. I regularly fly IFR. This spring, I updated the panel to all Garmin G3X Touch, ADS-B in/out, autopilot, IFR GPS. There was a very small learning curve. My instrument scan changed, and I had to get used to the tapes, especially on approaches. But it really was a small learning curve. After just a few approaches, everything fell into place. Now, I can't imagine going back. There is so much information at your fingertips. I truly believe I'm a safer pilot with all of this information, plus I do a better job at managing/monitoring my engine, too. The other unadvertised benefit is between the new avionics and a lithium battery, I saved 52lbs!
 
The one thing I notice most is how accurate the electronic AI is at displaying attitude. It's slightly different for every airspeed and loading for various flight regimes, but on the other hand very easy to set exactly the right attitude and power setting for precise IFR configuration.
Yes! To the point that there are constant complaints on a lot of various forums about how "my new AI doesn't show level in cruise, it's always two degrees nose down." Yes, exactly correct! And it will change based on how heavy you are, how fast you're going, and all of the other things that change AoA. (Yes I know what AoA is, but in level flight it's analogous to pitch.)

Glass lets us really see how various factors affect things like AoA and TAS. The changes aren't very big, and they were happening before but we just couldn't see them. Now, we can.
 
Confounding variable is that with glass almost always comes a competent autopilot. Was not always the case historically. Have flown both, and find that hand flying a six-pack in IMC for hours is easier, with less distracting information, than with glass. AP changes the calculus.

Since everyone has an iPad with FF now, it's not clear that the difference is really all that great, since a lot of the eye candy on the glass screens is equally well portrayed in FF. Often with automatic flight plan transfer.

Personally find the "original" GA glass, aka G1000, poorly thought out. Newer stuff is better. Also personally find that the entire comparison is moot unless flying IFR routinely - a compass and an iPad will always get you there VFR. Not that you really need the compass if you have an iPad.

Which comes full circle to OP and his friend - know of numerous fancy installs of glass done by owners who just like it, the 50-100k does not matter to them; if/when they want someone to help them figure the stuff out, either because they do a bit of IFR or because they can't read the book or both, it's clear that the new panel is no different to them than restoring a nice old car - just looks nice and cost be damned.
 
Confounding variable is that with glass almost always comes a competent autopilot. Was not always the case historically. Have flown both, and find that hand flying a six-pack in IMC for hours is easier, with less distracting information, than with glass. AP changes the calculus.
I would definitely buy that... I guess it could go either way, glass lets you see tiny excursions quickly and thus correct before altitude starts diverging. If you're willing to accept a bit of slop attitude-wise and not chase it, it's really easy to keep your altitude within about ±20 feet with glass. You won't even see the slop on the 6 pack, but you may end up having to spend more time correcting. All depends on your technique.

Since everyone has an iPad with FF now, it's not clear that the difference is really all that great, since a lot of the eye candy on the glass screens is equally well portrayed in FF. Often with automatic flight plan transfer.
Yes - I flew plenty of IFR with a ratty old KLN89B and an iPad for the first 5 years I had the plane. I do think that there's a lot of value in the improved map, flight plan transfer, WAAS capability, etc with the GTN750, and while I use the iPad somewhat less I can also use the two a bit differently than before. For anyone who trains on steam gauges and is comfortable with them, what I've got now is quite good: 6 pack with GI275 AI, and a 2-axis autopilot with preselect. I do like having full glass when it's available to me, but I can also live with spending all that money on avgas instead.

Personally find the "original" GA glass, aka G1000, poorly thought out. Newer stuff is better.
Interesting. How so?
 
Interesting. How so?
The G1000 is basically a 430/530 with a big screen. Same logic, way too many plies for most actions. The 750, on the other hand, is a much better interface, with redundant and complementary means of performing an action. Also believe it's meant to be designed such that any action is never more than two plies deep. A pilot's box, whereas the 430 and its descendants is a SW engineer box.

FWIW, find it much easier to maintain altitude within ± 20' with a simple steam setup, but that may all be muscle memory. The tiny excursions have a time constant that is too low for my taste in glass - guess the steam is somewhat more damped.
 
The G1000 is basically a 430/530 with a big screen. Same logic, way too many plies for most actions. The 750, on the other hand, is a much better interface, with redundant and complementary means of performing an action. Also believe it's meant to be designed such that any action is never more than two plies deep. A pilot's box, whereas the 430 and its descendants is a SW engineer box.
Yes - The G1000 is very much like the GNS series, and the G3000 is very much like the GTN series.

They do both have their drawbacks. The "groups/pages" thing on the GNS/1000 could be viewed as a bit clunky, but it does have a few buttons that get you directly to places (like FPL). I don't like how the GTN/3000 units make you go to Home for every. freaking. thing. I'm very glad I have my GMA 350c so I can just say "Show Traffic" and get directly to a different page. And everything still works correctly, like the Back button will still take me directly from traffic to maps if that's where I was. But, doing it without the 350 is very clunky and makes me wish it were easier to jump directly to frequently used stuff. The only exception to the "everything goes through home" is that you can tap the next leg at the bottom of the map and it goes to the flight plan. There's also the option of replacing one of your data fields with a button that goes to certain pages, but then you lose the data fields which I think are much more important. :dunno:

One of these days they'll come out with yet another new thing that will certainly be better while also leading to new gripes. ;)
 
… I don't like how the GTN/3000 units make you go to Home for every. freaking. thing. ….
It doesn’t have too, though.

From default nav page, map and flight plan pages are one click away. Back takes you to the menu. From any page long press home takes you yo default nav.

Most of my time spent on a GTN is the default nav page since I customize the six available fields. Flight plan is my next preferred page since everything from route to VNAV to SID/STAR/Approach loading occurs from there.
 
It doesn’t have too, though.

From default nav page, map and flight plan pages are one click away. Back takes you to the menu. From any page long press home takes you yo default nav.

Most of my time spent on a GTN is the default nav page since I customize the six available fields. Flight plan is my next preferred page since everything from route to VNAV to SID/STAR/Approach loading occurs from there.
This is where Garmin falls down in writing manuals. The existing ones are very dry listing of functions. It would be great to have a section called "cool shortcuts", an example being go to the flight plan page from the default Nav page by pressing on the magenta waypoint. There are a bunch of these, and they are in the manual, but buried in mind numbing and often repetitive text.
Another example would scenario based section. e.g. "how to fly an RNAV approach". It's there, but not in way that corresponds to the sequence used in flight.
The videos Garmin has on their website do a much better job, but don't tend to show shortcuts.
 
Yes! To the point that there are constant complaints on a lot of various forums about how "my new AI doesn't show level in cruise, it's always two degrees nose down." Yes, exactly correct! And it will change based on how heavy you are, how fast you're going, and all of the other things that change AoA. (Yes I know what AoA is, but in level flight it's analogous to pitch.)

Glass lets us really see how various factors affect things like AoA and TAS. The changes aren't very big, and they were happening before but we just couldn't see them. Now, we can.
Yep. I've had to relearn my "numbers" for IFR configuration and adjust for different CG loading. With two in front 90 kt and level flight is 4 degrees nose up and 2200 rpm (This is near max forward CG.) When I'm solo its 2 degrees nose up and 2200 rpm. Cruise settings have similar effects. The old analog AI, was "it's somewhere around 2 dots high," but it is so difficult to read accurately, you never notice the differences, and you cancel them out anyway by adjusting the knob (again and again). Having absolute and reproducible numbers is really nice, and you can definitely tell attitude differences of +/- 1 degree.
 
It doesn’t have too, though.

From default nav page, map and flight plan pages are one click away. Back takes you to the menu. From any page long press home takes you yo default nav.

Most of my time spent on a GTN is the default nav page since I customize the six available fields. Flight plan is my next preferred page since everything from route to VNAV to SID/STAR/Approach loading occurs from there.
I'm guessing you have a 650? Like the 430/530, the 430 had a "default nav" page, while for the 530 the default nav page was the map.

My 750 is the same way, I don't have a separate default nav page. I have a map page with 10 data fields (two of which are eaten up by the transponder controls). I still have four along the top and four in the corners of the map.

So, I can get to flight plan right away, and of course the map, but most often I want to switch to Traffic for example. Can't do it directly unless I wait for the "oh crap" alert. "Show Traffic" is definitely my most used voice command.

Another place I want to go fairly frequently is the VNAV page, and that is the one page in the entire interface that there's apparently no voice command for.
 
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