Training and Safety Tip: Check your expectations
I remember looking at the sectional chart before arriving at an unfamiliar airport and noticing that one of the runways had a right-hand pattern. I thought to myself, “Ah, I’ve got to remember that.” That, in itself, is no big deal; however, right-hand patterns are in the minority, and I know the danger of responding out of habit. I also knew that all my friends would be on frequency and listening, should I make a mistake.
As I flew back in to the airport, I began chanting a little mantra in my head: right-hand pattern… right-hand pattern… right-hand pattern…
And yes, everyone heard. And yes, I was teased mercilessly. But, of course, I deserved it.
The trap I had fallen into has a name. It’s called expectation bias, a type of pilot error profiled in the FAA’s Risk Management Handbook. Expectation bias is a flavor of human error that occurs when your brain processes information in a way that conforms to what you expect, rather than the way it is.
What’s really interesting about expectation bias is that, at least when it comes to communicating with air traffic control, pilots will often read back the unexpected clearance correctly, but then act on what they had been expecting, just like I did. It’s sort of like having a mis-programmed autopilot in your head.
Even though this happened to me on arrival, expectation bias errors are actually most common during taxi operations. This is partly because we are taught to look at our taxi diagrams before calling for a clearance, and to visualize the probable route. This sets the stage for the pilot to expect a specific clearance. The risk is even greater where we routinely operate, at our home airfield, especially when certain routes are commonly used.
So while thinking ahead of the airplane is good airmanship, it’s important to temper your expectations. Take a breath and be sure to double-check what you just heard before you act.
