Click, Look, twist
Adjustment knobs can be dangerous tools in the wrong situations and can cause big headaches. One experience I had with this was single-pilot IFR in a Cessna 172 with a G1000: I had just been given a frequency change, then right after I'd dialed it in and was reaching for the flip-flop key, a jolt of turbulence hit, scrambling the frequency and then switching it. As I reached over to fix it, I got another bump, thus pushing both frequencies off. Fortunately, I recalled and earlier frequency and was able to ask that controller for the new one, then got back under way without further incident. I realized later that a scrambled frequency wasn't that big of a deal. Twisting the altimeter knob while on autopilot, thinking it's the heading bug? That would have been much worse.
Learning from that, I developed the technique of click, then twist: grab a knob, click it one increment, look at the output, then when you see the desired output changing, twist it the rest of the way. Some airplanes, like the E175, are designed with different textured knobs to give you a tactile cue about what you're doing. This useful idiot-proofing design has been around since Alphonse Chapin, the father of modern UX, invented specific handles shaped for their purpose after a spate of B-17 crashes. Here you can see the big dimples in the mins next to the small ones for the baro knob:
Learning from that, I developed the technique of click, then twist: grab a knob, click it one increment, look at the output, then when you see the desired output changing, twist it the rest of the way. Some airplanes, like the E175, are designed with different textured knobs to give you a tactile cue about what you're doing. This useful idiot-proofing design has been around since Alphonse Chapin, the father of modern UX, invented specific handles shaped for their purpose after a spate of B-17 crashes. Here you can see the big dimples in the mins next to the small ones for the baro knob:
Even then, I always click it one increment first to make sure I'm not making a grave error.
Other panels, like the G1000s I used to fly more often, have the same knobs for COM, NAV, FMS, and ALT:
This means you need to be more alert when you reach over and start twisting, because you won't have the tactile reminder associated with each one:
This technique will save you from consequential problems. Having your baro off by .01, heading off by 1 degree, etc. will usually not be catastrophic. Sometimes going slow helps you get it right with fewer problems.
- Look for the desired value to change on the first click.
- If it doesn't change, click that knob one back.
- Look at where your hand was, then check that value to make sure it's still on target.
- Find the knob you originally wanted, then start over. When the desired output moves, spin it the rest of the way.
This technique will save you from consequential problems. Having your baro off by .01, heading off by 1 degree, etc. will usually not be catastrophic. Sometimes going slow helps you get it right with fewer problems.