Checklists and drills are jolly useful things. They jog our memories; they help us not to overlook important items. They also take off us some of the mental load at times of stress by ‘automating’ actions or sequences of actions that might otherwise absorb our thought and attention. But they have a downside.
Precisely because we sometimes do them without thinking, we also sometimes do them without noticing. And therein lies a peril. Here are some examples:
Take the common-or-garden Flapless Approach. If I had a pound for every time I’ve seen this happen then I’d be able to pay for avgas these days without wincing. The pilot turns onto base leg for a flapless approach. He knows what he’s doing. He’s relaxed and confident. He reduces power early just like he’s been taught. He remembers to take it right off and just to trickle it back on because he’s not going to have the extra drag to pull against. He trims for his flapless approach speed and he doesn’t lower flap ‘cos it’s a flapless landing, right?
He turns onto finals and calls “Finals”, just tickling the power to keep his angle of approach correct without upsetting his carefully held speed. He’s in the groove and he’s doing well. He moves his hands to the flap lever but he remembers just in time and he doesn’t lower the rest of the flap as he usually does because it’s a flapless landing.
He returns his hand to the throttle, concentrating on maintaining his approach; which is looking pretty good, by the way. And very often, perhaps eight times out of ten, he doesn’t remember to put the Carb Heat to cold.
Why? Because he’s got used to doing both actions together. He’s built up a little routine. The actions have blended themselves into one little semi-automatic sequence. ‘Check up the approach, turn onto finals, make the call, set the flap, set the carb heat’. Knock out one of those actions and there is a high probability that another one or two drop out also. Don’t worry, we’ve all done it.
Here’s another. We’re at the top of the climb on a warm summer’s day. The pilot levels off and does his FREDA check just like he’s been taught. He applies carb heat. He checks the fuel: the quantity is OK, the pressure is good, the pump is now off. He checks the radio, it’s set up as he wants it. He checks the engine gauges and they all look good. Everything is going swimmingly. He’s on top of the world. He checks the DI against the compass. It’s a bit bumpy so he squints at the compass as it dances about unhelpfully. It oscillates back and forth and he wants to believe that it is still aligned with the DI but, to his annoyance, he finds that it has wandered off by ten degrees. But he can’t be sure because it just won’t stay still. Just as he decides on 10 degrees of drift he has second thoughts and thinks that maybe it’s out by 20.
He now not sure, so he decides to split the difference and he resets the DI. He is then abruptly conscious that his look-out has broken down so he quickly breaks off the FREDA check and guiltily scans the horizon, picking up a dot on the horizon that he has to watch for a moment or two before he can ascertain whether or not it is a converging aeroplane. He decides that it isn’t and he then settles down to enjoy the flight, congratulating himself on his airmanship whilst he nudges the throttle open a touch because the revs have unexpectedly dropped. The altimeter remains un-checked and the carb heat remains set to Hot until he notices his mistake at the next FREDA check.
Why did this happen? Because his little FREDA routine was compromised by having to fiddle about with the DI and then by remembering the very real need to maintain a good look-out. Both are essential actions, but both had the effect of disrupting his routine such that he didn’t notice that he hadn’t fully completed the check. Again, we’ve all done it.
And another. The pilot runs through his pre-start checks. He’s in a bit of a hurry. He flicks the fuel pump On in order to check that it pressurises the fuel system correctly. It does, but he forgets to turn it off because he is already moving on to the next item on the checklist, keen to get the engine started and warmed-up without delay. He starts up, taxies, and a few minutes later he is at the Hold running through his pre-take off checks. He gets to Fuel on his list. He checks the fuel quantity, ascertains that he’s on the correct tank for take-off, checks the pressure and then he flicks the fuel pump switch, turning it Off, before swiftly moving on to set the flaps for take off. As the aeroplane climbs out a minute or two later he congratulates himself on a quick get-away, oblivious of the fact that his smooth-running engine is now solely reliant on its mechanical pump to keep it fed with fuel. The safety net normally provided by the auxiliary pump is no longer there. Or rather, it’s still there but he’s turned it off.
Why? Because he’s come to treat the Pre-Flight Check List as an Action List. That Fuel Pump part of the sequence has become an action in which he flicks the switch; not one in which he checks the pump. And in this case, because of an earlier error he flicked the switch Off not On. It’s easily done but it could have far-reaching consequences.
And finally, just to show that none of us are immune, here’s how the same sort of thing caught me out just last month. It was towards the end of a lovely day. I had my fifth punter lined up for a trial lesson in the Moth. Actually I had the fifth and sixth, but the sixth hadn’t turned up for the detailed pre-light briefing that I always give in the classroom. So I was slightly irritated that I was going to have to brief twice and also that I was now likely to be a bit short of time as a result. It wouldn’t matter normally but I had someone’s Skills Test to do straight afterwards and I didn’t want the candidate kept waiting. So I was suddenly under a teeny bit of time pressure and my normal well-practiced routine was starting to fray.
I landed with the fifth guy, refuelled and left the Moth near the pumps. I walked my pax back to the Ops Desk and there picked up the sixth guy who had by then turned up. I decided to do a briefing for him on the hoof. After all, he looked a sensible guy. And I’ve done this trip a million times, I thought. What could possibly go wrong? So very unusually I briefed him as we walked to the aircraft, answered his many questions, showed him round the cockpit and got him strapped in and helmeted so that we were now ready to start. I turned on the fuel, flooded the inlet manifold, blew it out, locked the cowling. “Throttle Set! Switches On – Contact!”.
I swung the prop and the engine caught first blade. Good old Gipsy. I walked back around and leaned into the cockpit and do all the post-start faffing about: turn on the other mag, check the oil pressure, set the engine to a comfortable tick-over, test the mags, plug back into the intercom to check that the pax was still comfortable sitting all alone in his cockpit. Then I fumbled about with my own helmet, turned on the video system, put on my jacket and finally locked the video recorder’s key-pad before tucking it into my jacket pocket. Phew; at last I was ready. I closed the throttle fully and then walked back around to the front of the aircraft to pull the chocks away. Guess what? No chocks. You could have knocked me down with a feather.
Now, I am meticulous, absolutely religious about safety when hand-swinging – particularly when hand-swinging my own aeroplane. I always tie back the stick, I always check that the throttle is fully closed for start, and I always put in the chocks. It’s a routine and I must have done it more than a thousand times. And in all that time I don’t believe that I’ve ever forgotten to put the chocks in. But I had this time, for sure. Why?
Well, I thought about it later that day when I reviewed the incident to myself. I believe that the seeds lay in the breaking of my well-worn routine. My classroom briefing covers the need for chocks – but I didn’t brief there as I normally do. When the Moth is at the pumps I always walk out via the concrete to pick up the big yellow chocks there – but this time I was too engrossed in briefing my pax as we walked, which I don’t normally have to do. When I was strapping him in I was conscious of the need to get started promptly so as not to delay the next guy’s exam. These are all reasons and not excuses. I’d done what I’d sworn I’d never do and I’d hand-swung an aeroplane without first chocking it. Luckily none of the other ‘holes in the cheese’ had lined up and no harm was done. The throttle was fully closed, the stick was fully back. The aeroplane didn’t move an inch. In fact no-one but me even noticed that the chocks were missing. But it was a timely reminder that none of us is immune to the perils of a broken routine.
So the message is this. checklists and routines are useful, nay they are essential. Remember that a check list is just what it says it is, it is a check list and not an action list. But in any event when, as often it must be, the check or routine is disrupted, then let a little red light go on in your mind. ‘Routine Broken: Sit Up and Pay Attention!” The normal routine that you are used to has been disrupted and something may be about to fall through the gaps. And it just might be something important. Like a set of chocks.
A few pointers to finish
- The Olympic restrictions are now lifted and normality has been
restored. Well done everyone on NOT getting caught out by the airspace restrictions.
- We’re approaching that part of the year when the setting sun
shines right down Runway 24 (thus lending weight, incidentally, to the theory that Old Sarum castle and its adjacent airfield were designed by the same firm of architects responsible forStonehenge). Do be careful if you are planning to return to land late in the afternoon. A setting sun shining in your face through a smeared or dirty windscreen can provide all the ingredients for a nasty mishap. So, keep the windscreen clean and think about what you are going to do if you can’t see well enough to land.
- Talking of hazy/low-sun situations, remind yourself which is
the most dangerous arc on which to keep a particularly close eye if you’re flying with a low sun and/or haze limiting your view in one particular direction. Well obviously, keep a good lookout in all directions; that’s taken as read. But the one to keep an even closer eye on is your view down-sun (ie, the clearest arc from your perspective). The reason? Because anyone converging on you from that direction is squinting into the sun or the haze and you can depend even less upon them seeing you. So you may be ‘looking for two’ in that direction.
Be safe: but never stop learning.
Regards,
David Wood