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Some thoughts on the state of instruments/avionics

gereed75

Well Known Member
I recently had a thought about the current state of cockpit instrumentation and avionics.

When I built those many years ago, it was in the infancy of reliable glass. For a variety of reasons, I installed a full set of steam gauges arrayed around an early Dynon D10 For primary attitude reference. Included were some fairly “primitive” navcomm equipment - A Garmin GNC 300, a venerable Kx155 with glideslope and a Garmin Mod C transponder ( a 325 I think) a basic CDI, good coupled autopilot. All good, capable and pretty snazzy at the time.

It wasn’t long that the whole shebang was “obsolete” as full featured glass became available. I soldiered on, even flying a fair amount of single pilot IFR.

Then came the first gen tablet based EFB’s. Wow what an advance!

Those tablets have gotten way better. Now no charts ( I carry two EFB’s - they are so cheap, why not have a backup). I have ADSB in and out (working great with my old transponder) That adds up to lots of GPS receivers, the comms are still working great, flying approaches with geo referenced EFB approach plates is a cake walk.

My point?? - in a way I feel like I leap frogged the whole “glass is great” gap. What I mean is that with good reliable basic instrumentation and nav, and good ADSB, and reliable capable tablet EFB’s, I have pretty much every capability that a full integrated glass cockpit has, but never had to actually go there.

In some ways I feel it actually might have advantages over fully integrated glass - it has more redundancy, I probably won’t ever button myself into a screen I can’t get out of at a critical time, it is comfortably old school and intuitive (at least to me)

Not knocking full glass, it is cool. But for those looking to buy older airplanes, or those looking to spend on new glass, it seems to have fewer advantages now than when it was replacing primitive steam gages and “interpret the needles” nav systems.

Am I missing something?
 
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I have Foreflight on my iPhone and my iPad mounted on the dash...love it. I also have a full EFIS in the panel in front of me and another EFIS with moving map right next to it. Those things together give me far more flight and performance data than my iPad does, but more importantly it also gives me my engine managment. Additionally, I can send flight planning data to it from my 430W, or I can enter a flight plan into it directly, or I can design a flight plan on my iPad at home, and upload it to the EFIS when I get to the plane. Then, if I want to, I can couple that flight plan into my autopilot. Naturally, my radios are run by the EFIS, so all the frequencies for my next airport come up on the EFIS and all I have to do it touch the screen to switch frequencies. Dizzying. But yeah....iPads are great.
 
screen brightness

I think your premise is sound. One factor that nudged me to install an EFIS is the screen brightness. The ipad is not bright enough on some days. Also, as MacCool mentioned, the engine monitors included with the EFIS are nice.
 
Old Glass

I have sort of a similar situation. I started out all steam with a vacuum system. I replaced the AI with a D10-A. Then I decided to get my IFR ticket and added a few things including an Trio Pro Pilot and a GTN 625 for IFR coupled approaches. I have a Garmin 796 portable which I kept mounted to the panel. Garmin Pilot app, GTN and 796 all connect to each other via bluetooth for flight plans and ADSB from GDL 50 mounted under the panel. As for engine instruments, I have some original Vans and some replaced with 2" MGL singles. All work great and most have battery backup.

I have a friend that keeps telling me I should take out all the old stuff and replace with a G3X touch setup. Don't get me wrong, If I was building now, I would go with that setup but the G3X was not available when I started my progressive upgrades.

So as it would be nice to have a great new panel, you know what they say, "if it ain't broke, don't fix it"
 

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If I'm not mistaken, one advantage of new glass is the data recording ability - both engine and flight data.
 
I learned to fly in 1970. I rebuilt an Aeronca 11AC with my father and he taught me to fly. On April 4, 2021 I will fly to celebrate 50 years since my first solo.

My father and I owned a J-3 Cub for 23 years and I traded it for an RV-12. I added a 2nd Dynon EFIS and two mini-iPads, both running ForeFlight. I can split the screens on the EFIS to have EMS on one and primary flight on the other. One iPad stays zoomed-in for close traffic and the other displays route and weather. I flight plan on my home PC and transfer to the two iPads via Cockpit Sharing with Bluetooth.

And then couple LightSpeed ANR headset with my hearing aids that use Telecoil controlled from an app on my cellphone. The background noise is so low it sounds like I’m flying a turbine.

As a retired engineer, it just amazes me to be able to share in this technology. Situational awareness and safety are greatly improved.
-
 

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With a first gen glass panel I do have good engine / fuel flow / limit warning displayed via a GRT EIS.

Screen brightness was definitely an issue with early EFB’s. I now run a Samsung Galaxy Tab 8 - no issues with readability.

With any modern flight following / planning software I can tap on airports and get all the info including metar’s and taf’s, just gotta knob in the freq’s - no big deal. I do not consider the inability to preload waypoints into the autopilot a lose of capability. If you can’t get the airplane pointed toward or coupled to a waypoint while airborne you have other issues. The GNC will load sequential approach waypoints and the autopilot will couple to them. Of course watching it all on the geo referenced approach plates, overlaid on the chart, switching to an airport diagram when on deck - just like or maybe better than some older integrated glass.

The one thing I thought about not having is synthetic terrain vision. I do have TAWS on the EFB. Might miss terrain vision in an IFR emergency, assuming it’s actually useful in such a case.

I agree, no engine data download record (EFB’s record flight data). That is a big nice to have feature that I am missing
 
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Glass or steam, you still have to be able to hand fly the airplane because autopilots fail and sometimes get set improperly. Fly the airplane. Tactical.

All the screens and displays can provide lots of information -- sometimes useful, sometimes superfluous, sometimes distracting. Strategic information.
 
Combination is risk mitigation

I think it's smart to keep a simple steam A/S and Altimeter somewhere in the panel to go with all the nice electrons dependent stuff. I love glass when it works, and most of the time it works, but sometimes it no work or the battery BMS no work, or a switch no work, or a wire come off, or a software glitch shows up, or the heat monkey makes the resister monkey crazy, or the canbus terminerator no terminate, or the temp probe craps out, or the backup battery lasts 3 min instead of 30, and so on. Having had to bring her back to earth with only the simple steam gauge a couple of times, its nice to be able to mitigate the risk a little with very little investment.

I write this while the next generation is staring at their smartphones screens right now and not looking around or out the window. While i am here judging them about being glass mad, I'm staring at my Ipad and placing an online coffee order. I'm pathetic.... hehehehe

The good thing is that you have the choice because its an experimental. So far, the superior folks that represent us hasn't taken that privilege away yet.

Good luck with your upgrades!
 
Good glass

A good glass panel presents additional information and in an intuitive and helpful fashion. For example, there's seeing airspeed 90, but then having a small scale beside it that shows the trend of the airspeed, for example what the current trend says the speed to be at in X seconds. So you're slightly slow on approach, but you see the small scale pointing downward, now you intuitively know you're slow and slowing. This needs a different correction applied if the scale was upwards indicating that you are slow, but increasing. Yes, you could always note the speed and come back the next time around the scan to see trends, but that takes longer.

Another big one on RVs in particular is the ability to enter Vne in TAS. Yes steam gauges can have a moving "barber pole", but I haven't seen one in an RV or any small GA airplane.

I'm not knocking steam gauges, they obviously work. However glass panels have vastly more capability and present more information in a more intuitive fashion. Glass also weighs less and costs less to install (some exceptions obviously). That's why everything is going towards glass panels. If I currently had a nice steam gauge set-up, I'd leave it alone. The cheapest panel is the one already in the plane. If it ain't broke, don't fix it.
 
The cheapest panel is the one already in the plane. If it ain't broke, don't fix it.

The problem with modern glass is that when it breaks, often the whole thing breaks. You can’t just replace your ASI, for example. And it does become obsolete. Sometimes that means that the newer version is faster-brighter-easier, and sometimes it means that the manufacturer no longer supports it and it can’t be repaired. I am going through that now. I had an Advanced Flight 4500...it was amazingly capable for 10 year old electronics and I had NO intention of upgrading it. Until it broke. The ADAHRS module went TU. Rob Hickman could have cobbled a fix for it, but I was faced with the problem that if I spent the money to fix it, I’d have a functional, but still-obsolete 10 year old PFD. Cleverly, they make a new version that drops in to the same panel cut-out so I went that way, but some day I’m going to be faced with replacing this EFIS. Or my Navigator, or my transponder, or something that won’t fit in this panel and I’ll probably be looking at a new panel. Then I’ll be forced to wonder if I should put all that old glass back in that new panel. *sigh*
 
Obsolete

I hadn't considered that avionics manufacturers would stop supporting older panels. That's quite unfortunate.

My concern with the thought of "obsolete 10 year old PFD". A steam gauge panel was is obsolete 20 or 30 years ago. They started showing up in airliners in the 80s. Obsolete isn't a reason to replace something or not like it anymore. My friend's 1970 Plymouth Barracuda 440 is also obsolete, but he's not getting rid of it.

I look at it like anything else. What's the ongoing cost of repair? Is replacement the more financially feasible option? If the necessary part needed for repair isn't available, that narrows down the options a bit ;). Keeping up with the Joneses will lead to frequent and expensive panel upgrades.
 
I hadn't considered that avionics manufacturers would stop supporting older panels. That's quite unfortunate. ...
Considering you can get a supported EFIS for about $1500 I don't think it's too big of a problem. If you find a supplier that will keep supporting the stuff outside the EFIS - like the autopilot servos, engine probes, etc. then an EFIS upgrade will be much less painless.

https://grtavionics.com/product/sport-ex-efis/

That said, I hope I'm back here in 10 or 20 years moaning that my EFIS is now obsolete! :D
 
you also need to compare it to the cost of maintaining the older panels also. How much have I spent over the course of my flying for gyro rebuilds, new vacuum pumps, and analog gauge rebuilds or replacements. the cost of a couple of gyro rebuilds covers the cost of a new efis screen.

bob burns
RV-4 N82RB
 
you also need to compare it to the cost of maintaining the older panels also. How much have I spent over the course of my flying for gyro rebuilds, new vacuum pumps, and analog gauge rebuilds or replacements. the cost of a couple of gyro rebuilds covers the cost of a new efis screen."

Probably not as much as a lifetime of batteries, update bundles, etc. What was once "free" to fly ifr - photocopied approach plate, or Fltplan.go, or the DOD area books at minimum cost, is now over a grand for the bundles annually. The airplane becomes unairworthy without the avionics updates and navdata bases. There is plenty of on going cost with the modern panel.

larry
 
It’s true that round gauges break too, so panel maintenance is always going to be a thing. But if your ASI breaks, you can buy a new one and pop it back in the same hole, same plumbing. If your EFIS breaks, there may or may not be a replacement that uses the same cutout, or it may or may not be compatible with other installed components. And now your choice is getting a new panel cut, and then re-install of ALL of your panel instruments. And then you have to decide if you’re going to put that old, old 430W back in the panel because it’s still working (for now), or if you’re going to upgrade to a different, current, navigator.

Advance Flight appears to be addressing that. They’re part of Dynon now, but their big thing appears to be custom panel re-design. Looks like a very cool option, but would likely be a $20,000 upgrade. IOW...one has to consider that they need to include in their long term maintenance budget, money for the possibility of a new panel every 10 years or so.
 
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dedicated portable

I like the dedicated portable because they seem more reliable than the tablets. I fly with two tablets because sometimes one will not initialize unless you have an internet connection (Google or Apple in the middle adds difficulty for the software guys). the dedicated portable has not had that problem for me. I had a wireless failure on an iFly dedicated portable that they repaired for $25 and in the meantime I used my neighbors iFly unit. one minute to install and carry on. you can't beat that ease of operation.

and since I use iFly for all, I only need one subscription to cover all my nav software. covers up to four units with plates. $150 per year total.
 
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Older gauges

While reading this thread I couldn't help but remember the good old days of vacuum pumps to run those gauges. Those trusty pumps that never seemed to fail or leak with their simple tubing and filters and that 1 inch gauge that was somewhere on your panel. All you had to do was pony up a thousand or so dollars every 600 hours to keep that reliability.

And those neat little stick on instrument gauge covers if it did. Then flying on compass, and turn coordinator. What was it? "ANDS" or the civil war thing, "the south leads".

John Koonce
N 78MU
 
The airplane becomes unairworthy without the avionics updates and navdata bases. There is plenty of on going cost with the modern panel.

larry

Sorry - not true. It may not be legal for IFR flight without up to date databases in the IFR navigator, but you can let everything else expire and use free charts outside the boxes to fly as much as you like. We have five airplanes with glass cockpits, three of which are IFR capable, and at this time, we only might keep one IFR legal - but all of them are “in a condition for safe operation” (the word “airworthy” doesn’t apply to E-AB’s).

Paul
 
funny!

While reading this thread I couldn't help but remember the good old days of vacuum pumps to run those gauges. Those trusty pumps that never seemed to fail or leak with their simple tubing and filters and that 1 inch gauge that was somewhere on your panel. All you had to do was pony up a thousand or so dollars every 600 hours to keep that reliability.

And those neat little stick on instrument gauge covers if it did. Then flying on compass, and turn coordinator. What was it? "ANDS" or the civil war thing, "the south leads".

John Koonce
N 78MU
John, I think you forgot the /s for sarcasm! :D
 
I agree. I really miss having a single point of failure with vanes that wear away (by design) and commonly fail at 500 hours while flying my family in the clouds! My favorite part was replacing the instruments that connect to that vacuum pump too! Gyroscopic procession and the DG was always fun to keep me on my game...that may be what I miss the most. :D

Joking aside it costs me $350 a year to keep my charts up to date in the IFR navigator and cost me a flat rate $500 when I had to send one of my 8 year old Dynon screens in for repair. After hundreds of hours traversing the continent with glass I cannot imagine going back to steam gauges. The cost to maintain the glass has been less than that for steam gauges for me and the increased safety with glass is not negotiable.

Did I mention the last time I tried to get a new display for my trusty KX-155 and what that cost for 68' Cherokee before we sold it? :eek:

While reading this thread I couldn't help but remember the good old days of vacuum pumps to run those gauges. Those trusty pumps that never seemed to fail or leak with their simple tubing and filters and that 1 inch gauge that was somewhere on your panel. All you had to do was pony up a thousand or so dollars every 600 hours to keep that reliability.

And those neat little stick on instrument gauge covers if it did. Then flying on compass, and turn coordinator. What was it? "ANDS" or the civil war thing, "the south leads".

John Koonce
N 78MU
 
Other ways to address Vacuum pump failure concern

My panel is a mix of steam, dual ILS, a 430W, and portables. It has evolved over time. I have XM weather on my 496 and Foreflight on the iPad with a Stratus. I chose to address the vacuum pump reliability issue by installing a wet (oil lubricated) vacuum pump. It is good for the life of the engine and beyond. I replaced my standby electric attitude indicator with a G5 plumbed to the pitot static system. The Stratus gives me yet another AHRS. I could fly the airplane in an emergency in IMC with different points of failure for hours. So far I have had no bearing issues with my AI or DG gyros after 1400+ hours. The plane is flown regularly (no aerobatics), which I have heard is good for the gyro bearings.

LeRoy Johnston RV-6A Esperanza
 
Won’t go back...

I’ve spent thousands of hours navigating behind nothing more than dual vor’s/ils/,dme, rmi/hsi. In the busiest airspace in the country. As the world moved towards RNAV arrivals and departures and approaches, the FAA basically converted these complex rnav procedures into a series of radial dme fixes and labeled it “for non-RNAV aircraft only.” They were often nightmares to fly with steam. I’m not EVER going to willingly put myself in a position of routinely flying in today’s airspace with steam gauges (IFR) alone.
Something else I didn’t see mentioned....how many of our airports and our alternates have an approach that a steam-driven a/c can legally fly without declaring an emergency? My 300xl can go direct, but fly complex approaches? My airport has 5 rnav approaches, but only one VOR-A. No matter how much I may or may not like my steam gauges...the changing IFR “system” is leaving us without many options. I’d say this fact alone will drive many, often kicking a screaming, into upgrading the panel.

(Edit: Not to undermine the abilities of the basic gps systems like the 300xl driving steam indicators...they are and were a SUPER tool to have. Im just saying that the SA gained from any of today’s glass outweighs what I see as a minor increase in the likelihood that I am forced to rely on my backup instruments.
 
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62 years old, learning to fly, bought a low hour 2012 Van's RV-12 already built with the Dynon Skyview System and 2 axis AP, from a multiple RV builder. A good plane for flying around the patch.

Original owner bought a redundancy package with old school AS and Altitude round gauges, also added a Dynon D1 horizon, airspeed and elevation gauge and Garmin Aera 550 Map with GPS coverage.

I just got a new Ipad Mini with 256 Gb, and will probably get Foreflight package for it.

Glass EFIS is all I know.... I will be finishing up my Private Pilot's license soon, Foggles hours and night time hours still needed, then the check ride.

I'd be lost in older conventional intrumented airplanes of the past, at least without Maps, GPS and ADS-B In and Out.
 
I recently had a thought about the current state of cockpit instrumentation and avionics.

When I built those many years ago, it was in the infancy of reliable glass. For a variety of reasons, I installed a full set of steam gauges arrayed around an early Dynon D10 For primary attitude reference. Included were some fairly “primitive” navcomm equipment - A Garmin GNC 300, a venerable Kx155 with glideslope and a Garmin Mod C transponder ( a 325 I think) a basic CDI, good coupled autopilot. All good, capable and pretty snazzy at the time.

It wasn’t long that the whole shebang was “obsolete” as full featured glass became available. I soldiered on, even flying a fair amount of single pilot IFR.

Then came the first gen tablet based EFB’s. Wow what an advance!

Those tablets have gotten way better. Now no charts ( I carry two EFB’s - they are so cheap, why not have a backup). I have ADSB in and out (working great with my old transponder) That adds up to lots of GPS receivers, the comms are still working great, flying approaches with geo referenced EFB approach plates is a cake walk.

My point?? - in a way I feel like I leap frogged the whole “glass is great” gap. What I mean is that with good reliable basic instrumentation and nav, and good ADSB, and reliable capable tablet EFB’s, I have pretty much every capability that a full integrated glass cockpit has, but never had to actually go there.

In some ways I feel it actually might have advantages over fully integrated glass - it has more redundancy, I probably won’t ever button myself into a screen I can’t get out of at a critical time, it is comfortably old school and intuitive (at least to me)

Not knocking full glass, it is cool. But for those looking to buy older airplanes, or those looking to spend on new glass, it seems to have fewer advantages now than when it was replacing primitive steam gages and “interpret the needles” nav systems.

Am I missing something?

Nope...not missing a thing
 
I recently had a thought about the current state of cockpit instrumentation and avionics.

When I built those many years ago, it was in the infancy of reliable glass. For a variety of reasons, I installed a full set of steam gauges arrayed around an early Dynon D10 For primary attitude reference. Included were some fairly “primitive” navcomm equipment - A Garmin GNC 300, a venerable Kx155 with glideslope and a Garmin Mod C transponder ( a 325 I think) a basic CDI, good coupled autopilot. All good, capable and pretty snazzy at the time.

It wasn’t long that the whole shebang was “obsolete” as full featured glass became available. I soldiered on, even flying a fair amount of single pilot IFR.

Then came the first gen tablet based EFB’s. Wow what an advance!

Those tablets have gotten way better. Now no charts ( I carry two EFB’s - they are so cheap, why not have a backup). I have ADSB in and out (working great with my old transponder) That adds up to lots of GPS receivers, the comms are still working great, flying approaches with geo referenced EFB approach plates is a cake walk.

My point?? - in a way I feel like I leap frogged the whole “glass is great” gap. What I mean is that with good reliable basic instrumentation and nav, and good ADSB, and reliable capable tablet EFB’s, I have pretty much every capability that a full integrated glass cockpit has, but never had to actually go there.

In some ways I feel it actually might have advantages over fully integrated glass - it has more redundancy, I probably won’t ever button myself into a screen I can’t get out of at a critical time, it is comfortably old school and intuitive (at least to me)

Not knocking full glass, it is cool. But for those looking to buy older airplanes, or those looking to spend on new glass, it seems to have fewer advantages now than when it was replacing primitive steam gages and “interpret the needles” nav systems.

Am I missing something?

In my opinion, not missing a thing.
Same path for me.
Same thoughts.
I hope to catch up when the open architecture (hardware and software) revolution finally hits and glass is replaced by a HUD, or better yet, glasses. Watching development and think we are getting close.
 
I have Foreflight on my iPhone and my iPad mounted on the dash...love it. I also have a full EFIS in the panel in front of me and another EFIS with moving map right next to it. Those things together give me far more flight and performance data than my iPad does, but more importantly it also gives me my engine managment. Additionally, I can send flight planning data to it from my 430W, or I can enter a flight plan into it directly, or I can design a flight plan on my iPad at home, and upload it to the EFIS when I get to the plane. Then, if I want to, I can couple that flight plan into my autopilot. Naturally, my radios are run by the EFIS, so all the frequencies for my next airport come up on the EFIS and all I have to do it touch the screen to switch frequencies. Dizzying. But yeah....iPads are great.

Just think how cool it would be with open architecture so you can run Foreflight right on you EFIS or run your EFIS on your iPad. Or maybe better yet, buy Garmin’s EFIS software and run it on your Dynon.
 
Not knocking full glass, it is cool. But for those looking to buy older airplanes, or those looking to spend on new glass, it seems to have fewer advantages now than when it was replacing primitive steam gages and “interpret the needles” nav systems.

Am I missing something?

No. At work I fly a state-of-the-airline-art 787, but in GA I designed my panel so an analog airspeed and altimeter were primary, and the Dynon acted as a MFD for NAV, EMS, etc..

The reason I did this was at work I have another pilot (or two or three) backing me up while I interpret what the display is giving me, but in GA flying I want to be able to easily see out the corner of my eye that my airspeed needle is at the 4 o'clock position and I'm safe, I don't have to run an OODA loop to read a tape to decide if I'm high or low on energy when turning base-final and looking for the guy who called on a straight-in approach without saying how far out he was.

I see people loading airplanes up with glass this and glass that, and I can think is "When the **** hits the fan, and you're looking through the soda straw because of stress, are you REALLY going to be able to remember to do all that AND fly the airplane?"
 
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