Attitude Indicator

I spent a few years in the Air Force (10, actually) in my younger days. My job was Avionic Navigation Systems. I remember one night when they asked me to do a "ride along" to see if one of our systems was working. It was a KC-135 out of Rapid City, SD. We started making runs between Memphis and Albuquerque refueling C-5's, at the time the world's largest aircraft. We had a pilot-in-training at the helm and a pilot-in-training in the C-5 and I was riding in a flying fuel tank with a refueler-in-training trying to stick a jet-fuel-filled stick into a small hole above the windshield of this plane while we flew at 400 mph. I was thinking, "That thing could suck us into one engine and probably not notice." Ah, yes, good times.

KC-135 refueling C-5

Well, that done (the thunderstorms stopped us early) (think about that for a moment ... fuel plane in the air, lightning, that kind of thing), we headed back home and I got to watch the ILS (Instrument Landing Systems) stuff I worked on in action. I sat in the jump seat behind the pilots watching the instruments (because, to be honest, there aren't many lights to see in South Dakota at midnight). It was odd. I could have sworn that I was sitting precisely perpendicular to the earth in my seat. I mean, I wasn't leaning or anything and the plane wasn't leaning as far as I could tell. Everything appeared to be parallel and perpendicular. But then I looked at the attitude indicator.

Aircraft Attitude Indicator

Yeah, that's right. Airplanes have an indicator that tells you the attitude of the aircraft. No, not how the airplane is feeling. For aircraft the "attitude" is the orientation with respect to the horizon. Seems dumb, doesn't it? As it turns out, it's not. Forces of which you're not aware -- forces like inertia and all -- will tell your brain that you are in one particular horizontal plane when, as it turns out, you're not. So there I am, perfectly perpendicular to the earth, as I said, and the artificial horizon on the attitude indicator is telling me that I'm tilted over almost 20° from perpendicular. Well, that can't be right! And then the runway lights came into view and, sure enough, we were banking. And I couldn't tell.

How does the attitude indicator know what I couldn't tell? It uses a gyro that gives it a fixed orientation to the earth. Turn the plane any direction you want and this thing won't be fooled. It knows what's up and what's down ... better than you do. Your internal sensors will tell you lies about the attitude of the aircraft. You need reliable, external sensors to get this right.

I think of that attitude indicator in a lot of conversations these days. I think it's interesting the parallel between an aircraft's "attitude indicator" and the attitudes of people that have shifted from "perpendicular". I recently saw a website with "hundreds of reasons" that Christianity is wrong. (I'm waiting for the sequel, "hundreds of reasons" why every other religion is wrong. Probably shouldn't hold my breath.) They listed some amazing arguments. Like, "The Bible assumes there are demons and everyone knows there are not." That is, this argument is based on the internal sensors without any external support. "It's true because I know it" without any other reason. In fact, a large number of the arguments on that site were based on this approach. One that amused me and saddened me at the same time was "Christianity is false because the 10 commandments didn't list a law against discriminating against LGBTQ persons." Wow. The Bible does list the behavior as sin (which, in the view of most people and in the normal definition of the term, is discrimination), but it's wrong for not making a rule against discriminating on that issue? And why is the Bible wrong on that point? Because everyone knows that such moral discrimination is wrong. The same issue. An internal attitude sensor without any external verification. It's the same approach you'll get on moral issues. Some people refer to a "moral compass" (had an interesting conversation with a few family members just the other day over that concept). Only it seems as if most people have their own "true north". The same issue. Internal measurements without any valid, reliable source.

I prefer to use a valid, verified source for this kind of stuff. I do this because I've been in an airplane and I know how screwy my internal attitude sensing can be. Now, let's see ... where can I find a good, reliable source for what is best for the human being? Oh, I know! Shouldn't the Manufacturer provide a user's manual for that? Oh, wait! He did! We call it "the Bible." I need that kind of gyro, always oriented to true perpendicular, always reliable, always right. That gives me a good attitude indication.