I can’t find itnow, but there was a little test where pilots were asked to perform tasks relying on the interpretation of speed and altitude tapes, and the error rate (as in wrong-direction corrections being applied) was higher for the altitude tape than for the speed tape, even for pilots with signifocant glass experience. So while we seem to adjust to a display where the scale moves instead of the needle (whch, together with the linearity, is the main difference between tapes and classic instruments, the representation is still maknly analog), there seems to be something about the altitude display that makes it more difficult to interpret.
I rather like the G1000, but I agree that the design of the controls is very poor. There are just too many possible ways of changing a setting: hardkeys, softkeys, menus, data fields etc. etc. and there doesn’t seem to be much, if any, system in what design choice was made for any particular setting. This makes the learning threshold for the G1000 needlessly steep.
Once you know you way around it is not bad at all and I much prefer it to analogue panels.
(Caveat: The G1000 is the only glass system I’ve used so I have nothing concrete to compare with.)
I just want to pick up on one point in the original response.
I’m from an IT background too, and for 3 years of flying my Tecnam with a Dynon D120 EFIS, I told everyone the same thing, that I just don’t like speed tapes. I always landed using analog, which was conveniently located in front of my face.
When building the RV10 I decided it was time to change. The biggest thing that convinced me was the screen going from 7 inch to 10 inch.
And sure enough it paid off, I’m now happy to land using a speed tape. And now I wouldn’t go back to steam.
I think that there is another point here, which is the size of the PFD.
I fly six-pack, G1000, G5/600 and Aspen on a fairly regular basis and one of the plus points for the Aspen is that the Selective Radial Scan is tiny. It can be done barely moving the eyes, whereas on G1000 the eye movement is similar to a six-pack.
When I first moved to glass, I too, found the tapes quite disorientating. Now I am used to them and am OK, but I agree with the comment that it’s all about bugging. I would find it very difficult to fly an altitude without a bug, that takes a lot of interpretation, while on a round dial it is obvious.
I almost always fly a light twin on short final at half way between blue and red lines (it just seems to work) which gives a great visual cue, but on a single I bug Vat as being the only way to get a quick visual reference.
I think it’s generally fairly well accepted that the best and most intuitive way of displaying something is a “analog” dial, round gauge or tape combined with a fixed position digital number. A “rolling” number in any form, is confusing. Most modern cars got this right.
We can get used to anything, even the most counter intuitive stuff.
If the display is digital or analogue/mechanical in a physical sense means nothing IMO.
I have so far only flown planes with 6-packs, so I cannot compare. For the top row at least you know more or less where the arrow is supposed to be, so even when looking outside it’s in the field of view, you don’t have to actively look at them all the time.
The local ATO does base training until CPL level with 6-packs, and makes transition to glass after. He claims some airlines won’t take fresh students that have only seen glass, as they are unable to use the reserve analog gauges in case of panel or electrical failure. Of course the recent planes that have only analog as reserve is only going down with time.
In terms of the readability of analogue over digital I am not convinced that the first is easier to read. I think those of us that have been around for a while have grown up with analogue displays. We are very accustom to them. That makes it more difficult to transition and may lead to the argument analogue is easier to read. There was an intersting study about people from tribes that had little or no exposure to the developed world. They found it very difficult to cope with straight lines because that was something they rarely if ever saw. I suspect the younger you are the easier, albeit even the youngsters and seeing more analogue gauges again. It would however be interesting to know if any studies have been done.
I think as many others have said glass displays need time, and with enough time (which will depend on each person, and probably some will always struggle) most will end up preferring glass. I think this is solely because glass displays are capable of conveying so much more information. I dont think it would really matter if you replaced the tapes on a glass display with an analogue style dial which are appearing in some high end cars. However I think the reason for replacing tapes with dials is that they seem retro which we seem to think is “trendy”.
Without doubt anyone who has not used a glass display before or who has limited time on a glass display should acquire or buy a PC simulator of the avionics. It is the best time you will spend and so much better than time spent doing the same thing in the air. It will become second nature which is the key, especially for IFR.
One of the advantages I think Glass might have, is that while checking your altitude / speed, you can still see the line of the AI. Or at least your brain will have it in it’s close periphery.
Probably makes a bit of a difference. The SR71 apparently had a very dim laser that would draw an almost unnoticeable AI line all along the cockpit, and I imagine they put it there for some reason.
No images in that wiki article, curiously. Google turns up nothing useful too, but it does turn up this patent.
