Earlier this week the NTSB launched a review of how glass cockpits have changed the safety of light airplanes. It is an important question, but like most discussion of advanced avionics, it misses the mark because it is too broad.
The electronic displays that have replaced the mechanical primary flight instruments in virtually all new production airplanes are not the issue. It is the information that is displayed on these PFD and MFD that matter. The NTSB is wondering if simply changing from the mechanical gyros and air data instruments to an electronic display of the same information matters, and the answer is no.
The important question is does the airplane have a fully integrated autopilot and flight director, and if so, have fewer pilots botched approaches and hit the ground? Does the airplane have a good traffic alert system, and if so, has it been involved in fewer midair collisions? Is an accurate terrain warning system installed, and if so, were there fewer controlled-flight-into-terrain accidents? Is there an altitude alerting system, and if so, were there fewer altitude deviations? Is there satellite weather, and if so, did pilots fly into severe convective weather less frequently?
I love glass cockpits and we will never go back, but the expanse of glass is only a canvas on which to present more information. A glass cockpit without a good flight director, terrain and traffic warning, weather information, and increasingly synthetic vision, is not going to make a difference in how well GA pilots do when it comes to controlling an airplane in IMC.
I hope the NTSB will refine its study and look at each of the new capabilities that have accompanied the glass revolution instead of simply trying to determine if a basic PFD makes a difference. It doesn't. But the glass display has made possible the delivery of new information that can ward off many of the most critical hazards of IFR flying and that's what matters, and I want to know how much difference that new information has made to safety.
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Submitted by ahwells on March 11, 2010.
Mac is right on target. I do have some information on XM weather that is related to the Scott Crossfield accident. When he flew into the convective weather, there was another aircraft nearby that had a Garmin 386 on board and operational. The pilot of the second aircraft, a Seneca, deviated around the cells that Crossfield couldn't see coming. ATC called the Seneca to see if that pilot could contact Crossfield when they lost him on the scope, and the second pilot also listened on 121.5 but did not hear a beacon. The second pilot's radar track on FlightAware showed deviation around the big cells - an abrupt change of course. I know the second pilot was using the XM weather on the 386 because the second pilot is my son.
Submitted by Hogey74 on March 11, 2010.
I agree. Aside from simply ignoring important points, maybe the numbers are not big enough to get significant results when looking at subsets of information that Mac has (I think) correctly indicated as being needed.
In a somewhat related point, has anyone heard about a study done recently looking at a very different way of presenting information on flat panels? It was in New Scientist a few months ago and a mate described it to me over the phone. They set up an artificial horizon that did not move and arranged a number like speed or altitude or heading to roll and move upwards and downwards to show the attitude of the aircraft. So, if you were diving to the right, a numerical representation of your airspeed (say) would be canted over to the right and well down below the fixed horizon. It sounds dead wrong to me but in this study it was found that people correctly identified the "upset state" of the aircraft and commenced correct remedial action much more quickly than with normal presentation of attitude information. Interesting, huh? I would have to try it myself to believe it however. Cheers John
Submitted by Chuck Clark on March 11, 2010.
I recall a review Mr. McClellan published a few years ago on the Chelton EFIS. I had just installed the Chelton EFIS in my King Air B-200 and thought that Mac missed the greatest value of the Chelton system. I've found the greatest value of the Chelton EFIS to be the presentation of the flight path vector.
Think lateral 'track' over ground and vertical 'track' for ascents or decents. The Chelton EFIS provides a prominent marker on the PFD depicting your craft's true flight path both laterally and vertically (as opposed to its heading, which can be considerably different from its lateral track with high cross-winds, or pitch attitude that can be high while you are descending under low power). The consolidation of these two valuable indications is shown as a circle on the Chelton PFD that provides a clear indication of where the aircraft is going. The Chelton EFIS also provides clear indications of both lateral and vertical targets of waypoints, fixes, etc. with 'highway-in-the-sky' symbology.
Can we all can complete ILS approaches to minimums on a partial-panel with severe cross winds? Assuming the Chelton EFIS and associated GPS sensors haven't STB, on final in IMC with the Chelton EFIS you see a 'synthetic' runway on the PFD, including any displaced thresholds, the landing zone, etc. The flight path vector on the PFD shows where you are going. Fly the plane to put the flight path vector on the syntheic runway 'numbers' in the PFD and you will hit them.
I've found the Chelton EFIS to be most useful in night approaches to uncontrolled fields without instrument approaches. You load the airport/runway, specify the approach descent angle you want (e.g. 3%, 3.1%, etc.) and the Chelton EFIS provides a 'highway' to the selected runway. The integral TAWS function depicts and warns against any terrain conflicts.
I think most critiques of 'glass panel' tecnology miss the point. I agree that if the glass panels simply portray the same data on a digital flat-screen, there's little benfit. If an EFIS can provide a flight path vector to the pilot, especially when coupled with 'synthetic vision' portrayal of terrain, three dimensional waypoints, and runway landing zones, it is a huge improvement in situational awareness and safety.
Submitted by tom connor on March 11, 2010.
I went to the Cessna TAA course on the C-182 Nav III for CAP and then tried to teach it to others under their guidelines. I thought they made it a lot harder than necessary and many pilots said no thanks. Personally, I don't see much difference from a similarly equipped steam gage aircraft. Having said that, there are few similarly equipped steam gage aircraft.
IMHO, a VFR pilot could care less if the panel is glass or steam, in fact for the person who falls in love with the pretty screens I think it is a detriment. But for the IFR pilot, the data fusion, geo-referenced presentation and synthetic vision is worth a lot of peeks out the window. Just as important is the elimination of the vacuum pump and associated instruments, or at least their demotion to second or third string.
I also own an aircraft and installed a JP instruments EDM-800, a Rocky Mountain microencoder and numerous digital engine instruments from Electronics International and use a G-496 for weather and sports. I lust for a Dynon D10 or higher to replace the Micro-encoder so I have a backup to the vacuum driven widgets. The in-flight and post-flight data analysis from the EDM-800 data recording has saved me many an unpleasant surprise, and I am also lusting after the JPI 830/930 so I can record more data and look in one place for it. Therein is the downfall of lots of data at various locations in the cockpit: Either something useful goes undetected or it's a bit busy. Keeping all the balls in the air between setting up a localizer/Glideslope and programming the G-496 for '[situational awareness' can be a handfull, and therein is the beauty of the tight integration in modern glass systems.
The FAA has redesigned almost all Montana ILS approaches by replacing marker beacons/NDBs with DME fixes or named waypoints. Hence a G-430W will soon replace a perfectly good Collins microline com/nav. Tied to the ancient Century I wing leveler with nav tracking I suppose that classifies the plane as TAA. It may not be as pretty as a G1000, but some say I can afford it.
Submitted by kglesq on March 11, 2010.
That the NTSB would commission a study that so completely misses the point of glass cockpits is disturbing.
In a direct apples to apples comparison, wherein the information being displayed on steam gauges is identical in content to that displayed on a glass panel, I would expect one could discern no difference in safety whatsoever.
As Mac noted, the difference is that the comparison is NOT one of apples to apples, but of apples to oranges. Glass does no better a job in displaying basic attitude, heading, and ILS/VOR info than a regular AI and HSI. The improvement comes from the display of map, terrain, traffic, and weather--along with the ability to superimpose that data over its sister components.
That the NTSB would fail to recognize that is unbelievable, and yet another waste of taxpayer money.
Submitted by mphelps on March 12, 2010.
Ahwells.
Could you contact me offline at eNewsletter@flyingmag.com?
Thanks.
Mark Phelps, Editor Flying eNewsletter
Submitted by pkelly on March 12, 2010.
Mac hits the nail on the head. The NTSB reflects the 'mainstream' government problem of drawing conclusions based on superficial evalution. If they would take the time to drill-down deeper to look at the underlying issues the end result would be much more meaningful. I'm convinced most of our goverment leadership (can be an oxymoron), is satisfied with doing the bare minimum, which is exactly why we have so much 'big goverment retoric', yet few problems get resolved.
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