Slaves to the checklist

Flip this switch, the fuel pump comes on. Set the throttle here, the engine burns 9.7 gallons per hour. We especially love the fact that we have checklists for all phases of flight. Many of us (guilty, yes that’s me) like a laminated spare in every pocket. And if we get distracted or realize we’ve gone out of order on the checklist, we simply start over at the top and all is right again. Neurotic? Maybe. Do we care? Not one bit. All of this contributes to a joyful overall feeling that our worlds are stable and predictable—until of course they’re not. We have a hotter than usual day and airplane performance changes. Or tower tells us to enter on a long final instead of the usual downwind, base, final sequence we have practiced. Or we pick up a little bit of ice or the wind speed increases or….

In certain instances, we may have to adjust our rigid checklist adherence. Yes, there are times when it’s wise to delay a checklist item or even skip it completely. Y’all put your pitchforks down for a minute and hear me out.

Here’s an account of an accident from the NTSB about a Piper Lance in South Carolina. “The pilot stated he had an uneventful cross-country flight and on the downwind leg of the destination airport traffic pattern, he switched the fuel selector from the right tank to the left tank and turned on the boost pump. While on short final approach, the engine started losing power and… subsequently impacted terrain about 600 feet short of the runway…. Examination of the wreckage by a Federal Aviation Administration inspector revealed damage to the wings, landing gear, and stabilator. The inspector also noted that although adequate fuel remained in both fuel tanks, the airplane fuel selector was in the ‘off’ position.”

A couple of things went wrong here. First, the pilot inadvertently selected “off” when he intended to select the left tank. But I’d argue that misstep could happen to anybody. It could certainly happen to me. The really avoidable mistake here is the decision to robotically follow the checklist and switch fuel tanks. Yes, the approach and landing checklist says fuel should be on the “proper” or fullest tank. However, if you are completing that checklist in the traffic pattern (rather than at a nice, safe altitude), the smartest choice would be to not touch the fuel selector at all. I see this on checkrides all the time in the Piper Archer. The applicant will have a timer set to go off every 30 minutes to remind them to switch tanks. This is great if we’re performing maneuvers up at a cruise altitude. But, if the timer goes off on downwind, I always ask the applicant to hold off until after we land. If something is going to go wrong (a failed valve, accidentally switching to off, and so on), I’d rather that happen when I have enough time to troubleshoot safely.

I’ve noticed a similar phenomenon on multiengine checkrides. I fly in and out of Olive Branch, Mississippi, where summers include 80 percent humidity and temperatures in the nineties, aka a density altitude nightmare. Multiengine checkrides call for a single-engine instrument approach. But what happens if you configure on profile, dropping gear and flaps at the final approach fix when you only have one functioning engine on an older airplane? You sink like a rock or worse, your airspeed degrades to unsafe levels while you attempt to maintain altitude. This is another case when you have to exercise some critical thinking. Just because the standard operating procedure calls for gear down when we intercept the glideslope, it might not be safe to do so in certain situations.

Several times through the years, I’ve had students ask me what power setting they should use in the traffic pattern or where they should turn base. “Over the lake or the red barn?” Or they’ll ask when they should pull power to hit a certain spot on the runway. “At the threshold or the five-hundred-foot mark?” I know they’re looking for that warm and fuzzy feeling definitive answers tend to give us. But we have to fly the airplane in our hands. Power settings change based on the performance we’re getting that day. We can’t always turn base at a certain landmark because no two airports are the same. We don’t pull the power to idle at the threshold every time either. What if we’re at a different altitude or airspeed than the last time? Decisions have to be made on the fly (pun intended). As much as I hate to admit it, aviation is probably good for those of us who gravitate toward its predictability. Airplanes teach us to adapt to consider the variables and realize when a change is needed. We can’t be slaves to our checklists.

myaviation101.com