Sunday, November 27, 2005

Glass Cockpit

Recent aviation literature has concentrated a great deal of attention on "glass cockpits" -- integrated, all-digital electronic instrumentation packages for airplanes. These have been common in business jets and airliners for quite a while, but recent activity has centered around general aviation airplanes of the types I fly. Until Friday, Nov. 25, I was skeptical of the claims of the reports in the aviation press. One is always hearing about some new device that will revolutionize the way we do something, but past experience shows this is often not true: in particular, digital instruments in cars, except for the Heads-Up Display (HUD) that lets you see a speed readout without taking your eyes off the road, always seemed to me to be different but no better. I was never convinced that any other presentation was as intuitive as old fashioned round, white-on-black gauges. Such gauges show you more than a digital readout: they show you whether the reading is high or low, and whether it's increasing or decreasing, even if you don't look at it long enough to pick out the numbers.

So, I was prepared to pooh-pooh the idea that glass cockpits, when they finally came to general aviation, would be a huge step ahead in performance. I was prepared to conclude they were different (and much more expensive) without being better.

Well, on Saturday I went flying, for the first time, in an airplane with a glass cockpit, the Garmin G1000. I'm trying to recover instrument currency/proficiency after my favorite two airports were closed by 9/11 in 2001, and then in 2003, my wife gave birth to premature triplets (one didn't make it, but the others are now free of medical complications). I'm now flying out of Easton, MD, on the Eastern Shore near our vacation house.

The plane was a Cessna 182, a model I've flown before, although not as many hours as my favorites, the Beech Bonanza, Piper Seminole, or Piper Arrow. Anyway, I relearned something someone told me many years ago -- maybe it was my own father. When you spend "enough" money on something, it shows. Cessna (and the owner) spent enough on this airplane. The instrument panel looks like something out of "Star Wars". There are no gauges except 3 backups for emergencies that you don't normally have to look at. The main instruments are 2 TV screens, about a foot wide and 10" high, one in front of the pilot and one in front of the right seat passenger. The pilot's screen, the "Primary Flight Display" (PFD), shows a graphic image of an attitude indicator, airspeed indicator, and other "aircraft control" devices, while the right screen, the "Multifunction Display" (MFD), shows a moving map with your route indicated as a bright line and your current position indicated as an icon of an airplane. Superimposed on that image, you also get "blips" where the other airplanes are that are somehow processed from the returns of the controllers' radar and/or the transmissions of the other airplanes' transponders. We unintentionally tested this feature when the instructor pointed to one blip and said the other airplane was closer than he liked, and he hadn't yet seen it with the naked eye, but it was always better to know it was there. Well, I looked in the direction indicated by the instrument and wow! There was an airplane on our rear quarter, flying across our wake. This is an incredible development for safety, taking most of the risk out of collision avoidance.

The magic MFD screen can also talk to weather radar stations and display precipitation echoes, lightning strikes, and freezing levels along your route, or indeed anywhere in the country, since it's tied in to XM satellite technology. It even shows topography because it's connected to GPS and has a terrain map stored in it. If you're getting too close to the ground, the image turns yellow and then red. (The instructor says you should turn this feature off as you approach your destination, because it will give you a scare when the map turns red as you descend for landing).

The mechanical gyros, vacuum system, and magnetic compass have been eliminated. A ring laser gyro (used in many military systems) provides attitude reference and a fluxgate compass, a solid state thing with no moving parts, provides the system with a north-seeking indication. Since all this is electric, there is a second power bus with its own battery that can run the PFD for about half an hour after the main battery and alternator have died. Air charts, including instrument approaches, are stored in the device's memory, along with all the radio frequencies, airport locations, runway lengths and orientations, and ground based navaid locations. A GPS and a VOR/Localizer receiver are built in too, although you can't operate them without going through the MFD. (There's no ADF, but since NDB's are all there in the GPS database, you can get the MFD to simulate one, with additional imformation showing how far away it is). The FAA says you still need to have the paper charts with you as a backup, but I think a skilled user of the G1000 might never have to take them out of his flight bag. It appears the manufacturer thought of everything.

I was impressed. The instructor says it usually takes 5 to 10 hours of instruction to get proficient with this equipment, but I think it's worth it. If I'd had something like this on previous flights, some of my unpleasant moments would have been much easier (like that time I had to land in Monmouth County, NJ, and stay there overnight because of thunderstorms on my way back from Martha's Vineyard to DC). It also happens that the airplane itself is a very nice new one with exceptionally roomy accomodations and an amazingly smooth-running engine that isn't even as noisy as most planes I've flown before. It even seems some 10 to 15 knots faster than any other 182 I've flown.

It also became just a perfect day for flight -- the wind died out, visibility was perfect, and as I flew, the sun set in an amazing display over the Bay. We landed just 20 minutes after sunset, too early to log the landing as a night landing, but it was dark enough for me to get the flavor of night flight again.

While I could pick a few nits -- the glide slope indications on the Instrument Landing System (ILS) graphic are tiny, inconspicuous blue diamonds, and the altimeter display is not intuitive -- I've changed my mind about glass cockpits. If I could afford to own an airplane, and the glass cockpit was priced within reason, I would get it. Thumbs up, Garmin.

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