I know you are a big proponent of TAA's but there should be some abilities in the aircraft for pilot's to have an out. So far every system I've flown, I've needed an out.Case 1: Brand new Piper Warrior with a Avidyne system on a VOR approach. Luckily in this aircraft they have a standby VOR gauge that I was able to use in navigation in conjunction with the standby flight instruments. I completed the approach old school style with one old CDI head to cross reference fixes and land in a spring hailstorm. If not for the standby CDI or knowing how to use it unlike many magenta pilots I would have had to stay up till the storm passed or diverted 50 miles to wait for the storm to pass.Case 2: In a Beechcraft Sundowner coming in on a GPS approach we lost RAIM then lost all GPS indications before crossing the FAF. Had to go miss and come back around on the old ground based stuff.Case 3: In a G1000 Cessna 182T was another fun one with an all glass cockpit. We lost everything again for a few minutes and had to fly off only a compass and attitude indicator. Really a pain when you are in the rain, IFR, night and in the mountains. Would have been a lot better if these G1000 had back up nav systems so we could triangulate our location.

Case 2: But that's OK, nothing to worry about... We'll just go ahead and continue to decommission NDB's and VOR's since we have this high-tech GPS thingy... Let's just not talk about how fragile the GPS infrastructure really is.Case 1/3: While you don't specifically mention what failed in the Warrior, what was the root failure in the Skylane? The systems are specifically designed with redundancy, so to lose the entire thing would have meant multiple, simultaneous failures. At that point, if the system is being operated as designed, you're entering statistical anomaly zone. I'd be curious what the final determination of the cause of both those failures you listed was.While having backup instrumentation in a glass a/c is a good idea, at what point do you draw the line? Do you have a complete set of traditional steam gauges as a backup in case the glass fails? At that point, what's the use of the additional weight of the glass? You'll never be able to achieve 100% reliability in any avionics (at least not what people would be willing to pay). Don't get me wrong, instrument pilots need to know WHAT their instrumentation is telling them, HOW it's deriving that information, and then DETERMINE if what's being told them is accurate. If a pilot wants to blindly follow what the magical screen is telling them, and fly into a mountain, and kill themselves, that's an ADM issue, not an avionics one.Interesting question: If you had a student come to you, in their own plane (a brand new C172 NAVIII, which they earned their PPL in) and want you to teach them so they can obtain their instrument rating, in said plane. Would you require them to go fly steam in another plane so they know how to do it "olde skool"?

Case 2: But that's OK, nothing to worry about... We'll just go ahead and continue to decommission NDB's and VOR's since we have this high-tech GPS thingy... Let's just not talk about how fragile the GPS infrastructure really is.

It is scary how easily it can be jammed. Another related story, our school aircraft were used for a little testing. GPS was NOTAM'ed out of service for the area around our airport. Well here comes in a new Wedgetail. Very cool sight watching it fly low level around the basin. Then a call went out over the radio asking what GPS Lats/Longs were. Everyone reported back with the same Lats/Longs. A quick thanks for the help from the Wedgetail and they bugged back out over to Seattle. We were thinking it must have been some sort of GPS jamming/repositioning for diverting missiles.

Case 1/3: While you don't specifically mention what failed in the Warrior, what was the root failure in the Skylane? The systems are specifically designed with redundancy, so to lose the entire thing would have meant multiple, simultaneous failures. At that point, if the system is being operated as designed, you're entering statistical anomaly zone. I'd be curious what the final determination of the cause of both those failures you listed was.

Case 1 was a loose connection on the Avidyne. I had it go out a second time and had my camera with me and I attached that picture. Case 3 is still unknown to me but it most likely was a software glitch and came back after resetting the system.

While having backup instrumentation in a glass a/c is a good idea, at what point do you draw the line? Do you have a complete set of traditional steam gauges as a backup in case the glass fails? At that point, what's the use of the additional weight of the glass? You'll never be able to achieve 100% reliability in any avionics (at least not what people would be willing to pay). Don't get me wrong, instrument pilots need to know WHAT their instrumentation is telling them, HOW it's deriving that information, and then DETERMINE if what's being told them is accurate. If a pilot wants to blindly follow what the magical screen is telling them, and fly into a mountain, and kill themselves, that's an ADM issue, not an avionics one.

Well the glass is saving us 300 pounds in the King Air. Steam backups are airspeed, altimeter and attitude. I don't think it would add more than 10 pounds to put a CDI in or even better a RMI that way we have a backup directional indicator because a compass is about as useless as fuel on the ground in that airplane. The problem is not when the screen is working but when it goes out and even the best of pilots will have very little information.

Interesting question: If you had a student come to you, in their own plane (a brand new C172 NAVIII, which they earned their PPL in) and want you to teach them so they can obtain their instrument rating, in said plane. Would you require them to go fly steam in another plane so they know how to do it "olde skool"?

I've done this to the client in his 182T. We did a few full IFR cross countries to see how he would do. If they don't want to I am not going to push it on them but I let them know how important it may be in the future even if they never think they will ever be in a steam airplane again.Let me try the attachment again.

It is scary how easily it can be jammed.

What's even more scary is how much of our technological infrastructure (not just positioning) relies on GPS, specifically timing. I remember the GPS outage in San Diego a few years ago, which was caused by the Navy conducting testing on one of their shipboard arrays. Was causing significant interference in the L band, and the first indication that GPS wasn't working were airborne GA pilots making reports to ATC.

Case 3 is still unknown to me but it most likely was a software glitch and came back after resetting the system.

Wouldn't surprise me. The only full-blown system failure I've had with glass (specifically the G1000) was software related. Apparently they loaded the version for the G1000 with the Garmin Autopilot (which the aircraft didn't have). Resulted in a full blown system failure in flight.

Yeah the G1000 failure occurred after they updated it to be able to use WAAS.

Yeah the G1000 failure occurred after they updated it to be able to use WAAS.

So Chris, this is what I've taken from what you've said about avionics failures: Don't let you near them.

So Chris, this is what I've taken from what you've said about avionics failures: Don't let you near them.

Pretty much I've seen almost every failure except for a complete display going black.

I had an altimeter failure ( along with prop overspeed and autopilot problem) in imc (steam Gauges) over the Smoky mtns back in the 90's. Guess what I used to save my bacon?-the altitude readout on a state of the art at the time Apollo 920 portable gps!

I had an altimeter failure ( along with prop overspeed and autopilot problem) in imc (steam Gauges). Guess what I used to save my bacon?-the altitude readout on a state of the art at the time Apollo portable gps!

And don't mention.............that if it comes to mountains, that today's GPS readings will be within feet, versus a possible several hundred from an altimeter reading. Of course it's the reading, that's used for seperation purposes. And yes, I'm still not following this total thread. It's still a waste of time. Perhaps it was mentioned and perhaps not................but one of my GPS equipped aircraft would have never flown into Superstition mountain, as one did last week.I've seen what moving map GPS is capable of, over the last 18 years. It only gets better. To belittle it, with multiple excuses, is beyond my imagination. I reserve that for student pilot forums, flight sim forums, and instructors who are not up to date with current technology, and still push the old values to the extreme.I will not read threads like this day after day, because it only p***** me off. Thank god, that I do participate in forums, where this technology is the correct way of doing things. All I can say to simmers and students, is open your horizons. Don't just go by a few examples, presented by those who feel that GPS should be regulated to the back seat, because it's a crutch or something. I'm sick and tired of airplanes flying into terrain, when they don't need to. That is all there is to it.L.Adamson

I will not read threads like this day after day, because it only p***** me off. Thank god, that I do participate in forums, where this technology is the correct way of doing things. All I can say to simmers and students, is open your horizons. Don't just go by a few examples, presented by those who feel that GPS should be regulated to the back seat, because it's a crutch or something. I'm sick and tired of airplanes flying into terrain, when they don't need to. That is all there is to it.L.Adamson

I'm curious who you're referring to? Lol. The point is people should learn to use both. Get a grip.

And don't mention.............that if it comes to mountains, that today's GPS readings will be within feet, versus a possible several hundred from an altimeter reading. Of course it's the reading, that's used for seperation purposes. And yes, I'm still not following this total thread. It's still a waste of time. Perhaps it was mentioned and perhaps not................but one of my GPS equipped aircraft would have never flown into Superstition mountain, as one did last week.I've seen what moving map GPS is capable of, over the last 18 years. It only gets better. To belittle it, with multiple excuses, is beyond my imagination. I reserve that for student pilot forums, flight sim forums, and instructors who are not up to date with current technology, and still push the old values to the extreme.I will not read threads like this day after day, because it only p***** me off. Thank god, that I do participate in forums, where this technology is the correct way of doing things. All I can say to simmers and students, is open your horizons. Don't just go by a few examples, presented by those who feel that GPS should be regulated to the back seat, because it's a crutch or something. I'm sick and tired of airplanes flying into terrain, when they don't need to. That is all there is to it.L.Adamson

Now don't get your panties in a bunch.The point is that pilot's should not rely on it all the time, which sounds like what you do.

And don't mention.............that if it comes to mountains, that today's GPS readings will be within feet, versus a possible several hundred from an altimeter reading. Of course it's the reading, that's used for seperation purposes. And yes, I'm still not following this total thread. It's still a waste of time. Perhaps it was mentioned and perhaps not................but one of my GPS equipped aircraft would have never flown into Superstition mountain, as one did last week.I've seen what moving map GPS is capable of, over the last 18 years. It only gets better. To belittle it, with multiple excuses, is beyond my imagination. I reserve that for student pilot forums, flight sim forums, and instructors who are not up to date with current technology, and still push the old values to the extreme.I will not read threads like this day after day, because it only p***** me off. Thank god, that I do participate in forums, where this technology is the correct way of doing things. All I can say to simmers and students, is open your horizons. Don't just go by a few examples, presented by those who feel that GPS should be regulated to the back seat, because it's a crutch or something. I'm sick and tired of airplanes flying into terrain, when they don't need to. That is all there is to it.L.Adamson

To be honest, your aircraft would have quite happily flown right into the side of Superstition mountain without a care in the world with all the latest avionics. The difference is in the PIC being able to manage the data that is being presented, interpret it, and finally make proper decisions based on it. As I see it, the argument isn't the fallibility of modern avionics, it's the fallibility of the person using it, ESPECIALLY one that isn't properly trained. I can teach a monkey to press DIRECT->TO, but you can't teach one to say "Hey, this doesn't seem/look right". The problem I have is with pilots who do push the DIRECT-TO button, and have absolute faith that the avionics will keep them out of danger, without any appreciation/training in what feeds the avionics, and the base/root information that is just being displayed to them in a different form.This is no different than the concept of teaching a professional mariner the fundamentals of celestial navigation. Is it required with this new fanged wizardry called GPS? Absolutely not. But if you don't understand the fundamental concepts, when GPS gives you a bad position (perhaps due to really poor HDOP), you won't understand why, what is happening, and take appropriate action.It's about the pilot, NOT the technology.