Tuesday, December 16, 2014

Flying An All Digital Glass Cockpit You Had Better Have Some Analog Back Up.........

As it is approaching Christmas, I am going to offer a present early, an abbreviated blog. Do I hear you cheering out there? Well, here goes. This is aimed at you digital types, with all glass cockpits. In case you missed it, all glass.  Do you have any back-up analog instruments? No. Well here is why you need them if you do any IFR flying in real weather conditions.  Let us suppose that you are on an ILS  instrument approach with a visibility of ½ mile and a ceiling of 200 to 300 feet. I’ve been there many times and it not only requires precision, but an alternative option. The option to quit the approach if it is not working out, for whatever reason.  What if at the last few feet of your descent, the digital (glass) system fails? Yes, just goes blank. If you have your analog gauges insight and working, you should be able to institute a missed approach.

Why am I going there? Because in reviewing  some glass cockpit configurations, I fail to see a complete or good partial analog back-up system. At the very least there should be an airspeed indicator, artificial horizon and altimeter. What about compass heading, rate of climb/descent etc? I think it could get pretty hairy quickly, especially if you are not practiced in this kind of situation.

Well that reminds me of a trip I had with my boss, and working associate in the company Piper Pa-34 Seneca.  This was all analog back in the mid 70’s. Nice planes as long as both fans were going and if you weren’t in a hurry. I was flying in the right seat, my boss was chief pilot in the left. We were getting vectored  for an ILS approach to runway 28 or 24 at Cleveland’s Hopkins,not sure which at this time. All at once my associate asks me to take over and fly the approach. I was shocked when he admitted that he hadn’t obtained his IFR ticket yet, something I hadn’t known. As I was legal and up to date, I accepted the offer. There was a problem in that I didn’t have a complete set of gauges in front of me and had to look at his for some data. The thing that I remember was craning my neck and struggling to see the ILS needle. Well, anyhow it turned out OK, with us breaking out at about 350 feet above the ground, with the runway barely in sight. The landing was good and we taxied to the gate and shut down all systems. That night I had an extra brew.

The moral here is that you never know when a problem will occur. The better prepared you are, the better you can handle the unexpected.

Have a Merry Christmas,  a Happy Hanukkah or whatever you celebrate, and a Happy New Year.

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