Glass Panels

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I am curious if you have any thoughts on the pros and cons of Glass
panels. It would seem that all the manufacturers have jumped on the
band wagon, and that all future aircraft will be equipped with glass
only. Are glass cockpits really that good? (I have never flown one.)
You have written a very candid review of the Cirrus aircraft. Would
you consider writing a similar article on your experiences with glass
panels in general? Is there any evidence that Glass panels are safer
to fly than traditional panels? Is a low-time pilot better off in a
glass cockpit, or actually worse off? Does the FAA allow instrument
training and IFR flight tests on glass panel aircraft? (I assume they
do) Have any of these "glass only" pilots been able to transition
sucessfully to a traditional panel? Is it true that there are
expensive maintenence contracts, and that they are hard to read in
direct sunlight? Are they prone to sudden and complete failure?

-- David Sanford, September 26, 2008


I think we should step back and ask what the purpose of the panel is. In visual conditions, the panel is checked about 5 percent of the time to make sure that airspeed and altitude are reasonable. The pilot would also check on the engine and fuel situation. Current glass panels use an airspeed tape rather than drawing a round dial. The airspeed tape was developed for airliners where holding an assigned airspeed is an important and common task. The round airspeed indicator is, I believe, much more useful for GA flying. A quick glance will tell you roughly where the current airspeed falls in the range of acceptable airspeeds. In a GA plane it is much more useful to be able to see "airspeed close to stall" or "airspeed close to red line" than "airspeed exactly 210 knots and trending toward 215".

In instrument conditions, it has been demonstrated by 10-year-olds with no formal training that the Microsoft Flight Simulator view of the world is ideal for novices. GA glass panels are beginning to get the synthetic terrain presentation that has long been common on the PC desktop, so in that sense the glass panel should be hugely better for low-time pilots tasked with flying instrument approaches.

I believe that there was a NASA study comparing the highway-in-the-sky presentation of the new synthetic terrain panels against the traditional 6-pack round dials. High time airline pilots performed about the same, but the low time pilots were much more consistent with the highway-in-the-sky glass panel.

To your questions... Will I write an article on glass panels? It probably wouldn't be useful because all new airplanes come with glass panels anyway. Are glass panel airplanes safer? I think a synthetic terrain glass panel should be significantly safer. There are more airline pilots who have crashed Boeings into mountains than there are 10-year-olds who unintentionally crash Microsoft Flight Simulator into a mountain. Is a low-time pilot better off with a glass panel? If he or she is going to fly VFR-only, I don't think it makes any difference because the primary task is to look out the window.

Does the FAA allow IFR training and checkrides in glass panel aircraft? They do, though partial panel is slightly different, e.g., in the Cirrus the examiner will fail the primary flight display and have the applicant fly an approach using the backup round dials. There are definitely a handful of guys who've trained in modern airplanes and ended up transitioning back to round dials when they moved up to a used Piper Malibu or similar. I haven't heard of anyone having trouble with basic attitude and airspeed control, though God help me if I had to fly a missed approach and hold using an NDB instead of the Garmin!

Are the glass panels tough to read in direct sunlight? Maybe slightly, especially if there is dust on the screen. But if you're getting direct sunlight into the cockpit it is a pretty good day for flying and you can get almost everything you need by looking out the window.

Maintenance contracts? No. You do pay for software upgrades if you want them. You pay for Jepp database updates if you want convenience and to do GPS approaches, but you'd pay for those in a steam gauge airplane equipped with GPS.

Sudden and complete failure? The Avidynes in the Cirrus have behaved themselves ever since the latest software upgrade. I've never seen a Garmin G1000 fail, but I did hear of a complete all-systems G1000 meltdown in an early Cessna Mustang. This was due to a software bug that became the subject of a service bulletin.

-- Philip Greenspun, September 28, 2008

I am hoping to talk Phil into writing an article about glass panels in general, but I would like to hear from others who have comments about glass panels as well.

-- David Sanford, September 26, 2008

I have never heard of any COMPLETE failure of a G1000, in the mustang, it was NOT a complete failure. I fly and work on the G1000 most every day, the software is different for each plane.

As far as safer it would be hard to compare because ALL G1000 plane have a auto pilot and that is what really make it safe along with the terrain data.

It is the way things are going to be in the years to come, Most all plane come from the factory with glass and most are the G1000 in GA. integration makes thing flow allot better than with steam gages. If you do fly IFR by hand then the BIG horizon makes it much easyer to fly and having the airspeed and altitude are great to use when you get used to them.

In Oct or Nov the (SVT synthetic vision) will be available for all the G1000 Cessna's. That is one of the good things about the G1000 system is we get new software every year at no cost that is like getting a new feature added to the system. (the SVT will be a added feature at a cost)

Resale value is a thing to think about because there is a big jump from steam to glass. In the G1000 Cessna's we have not only LNAV but VNAV that is all integrated and the altitudes are all loaded for you for a approach from the Jepp NAV data and will give you a glide slope like indication to fly by, but if you have the GFC700 auto pilot it will all couple all the way down to DH.

I could not tell you much about the Avidyne I have never flown one, but I do not see it being around long now that the one last hold out Cirrus is now using the G1000 in the top of the line planes.

-- john jones, September 28, 2008

It will be interesting to see if SVT and more sophisticated autopilots result in a better safety record for planes that are equiped with them. Thanks for your comments!

-- David Sanford, October 6, 2008

It may make more pilots want to scud run with SVT.

-- john jones, October 19, 2008