Springfield Chapter Missouri Pilots Association

June 2002

Flying Journal - Another Perfect Attitude Indicator Saturday

ATTITUDE INDICATORS, PART I: We were a little skittish after our total electrical failure last month. But it was a perfect Saturday for flying-if you're a duck! A ceiling of overcast clouds at 300 feet. Wait, now the ASOS is saying 500 feet-no, 300 again . . . but now it's 300 BROKEN. Wait a while . . . la-de-da, ho hum . . . Oh, 700 broken, now 900. Check the forecast and radar again. Cell phone consultation with my student. Actually, he had wanted some more actual IFR, but it would be our first actual in this different, larger aircraft, with an old, very on-standard instrument panel scan pattern.

I was legally current, but it had been 5 months since my last proficiency check. I just noticed the NTSB has released the final report on the Carnahan crash. Probable cause: spatial disorientation from moving head back and forth to include the secondary attitude indicator on the co-pilot's side in the instrument crosscheck. As a CFII, I am practiced at cross-panel IFR, but I suppose it's a long way across the panel of a Cessna 335, as it is on this PA-32.

Anyway, we were not eager to encounter low IFR so he ran an errand. I graded papers while waiting for him at the airport. The ceiling is now fairly consistent around 900 to 1100 feet, perfect for this stage of instrument training-the real thing, but plenty of room underneath if anything goes wrong.

Runway 32 at SGF now has the full length available and we took off from our old secondary runway that's now the primary. I was wondering if the only constant really is change? Of course I'll bet I'm not the only one glad that common sense has prevailed and short-term parking at SGF is open once again. Departing to the northwest, somewhere over Willard, my student checked in with Departure Control about the time we entered the swirling bottoms of the clouds. I sense he is drifting past our assigned heading. I glance at the attitude indicator to check his bank angle. Well, I know this plane doesn't have an attitude indicator, but the older artificial horizon. When you are used to the other, this one may appear to be reversed, like shooting a back course approach, or crossing your hands on your bicycle.

The strange instrument has caused him to correct in the wrong direction. I detect rising concern in his voice. I resist the urge to say, "See? That's what killed Buddy Holly and Ritchie Valens. You know, 'The Day the Music Died?'" But we'll talk about that later.

Last time I did that, an avionics company immediately got to sell a new attitude indicator. Reverting instead as trained to professionalism, I just point out the actual horizon line and draw attention to it instead of the bank marks at the top. He corrects appropriately, relaxes, and we continue our approaches uneventfully but alertly. At 3000 feet, we are comfortably enclosed in soft white clouds, with occasional reassuring glimpses of the ground below. We can tell the ceiling continues to lift when the controller calls VFR traffic for us two miles ahead at 2500. All we can do is report we are still in IMC. The Saturday VFR chowline is beginning to form on its way to Bolivar.

ATTITUDE INDICATORS, PART II: On June 5, Missy Shelton from KSMU News called me. Someone at the station remembered I used to announce there and also was a flight instructor. They wanted a reaction to the Carnahan report. I don't know if I got my point across or not. I suspect the general public (and certainly the family) will focus on the "instrument failure." But I am pretty sure most instrument pilots would feel that failure of an attitude indicator should not in crash.

Remembering that my vacuum pump failed on my first flight as PIC on an IFR flight, I resolved when I became an Instrument Instructor to be sure and make my students practice lots of "partial-panel" work with various simulated instrument failures. Of course Carnahan's Cessna 335 had that second AI, which may have been a mixed blessing, if the cross panel view led to spatial disorientation? While losing any gyro instrument is probably more serious than a blow-out on a car, we really wouldn't expect either to cause a fatal crash, but we all know that both incidents could, depending on the particular situation and the reactions of the pilot or driver.

ATTIDUDE INDICATORS, PART III: It was great to have almost an entire hour of actual IFR training on a fine Saturday. About the time we finished it became good VFR weather. Of course I figured my student would be ordering up a new attitude indicator, as he did when he upgraded his previous plane. But guess what? Being a very thorough researcher, he discovered that the autopilot system (which works fine) operates entirely from the old artificial horizon, and would also have to be replaced to upgrade, a much greater expense than just the AI. So I guess we'll become expert at flying with both types of instrument.Whatever kind of instruments you are flying, beware the fast-developing summer thunderstorms and fly safely!


[Copyright 2002 - Earl Holmer]