I am not a nervous flyer, but every once in a while I will observe something that concerns me.  Inevitably this leads to an internal debate about whether I should second-guess the pros. After all, the pilots have wall-to-wall indicators and sensors to monitor problems. Flight attendants have heard it all, too. What makes me think I have noticed something life-threatening that they haven’t?

Recently, I watched out the window as my plane was de-iced, and there was not a doubt in my mind that a foot-long patch of ice remained on the top of the wing. I worried. I mean, how much experience could de-icer guys in Charlotte really have? And who checks their work? Luckily, the more rational side of my brain restrained me from calling a flight attendant over and looking like an idiot. Ten minutes later (once we were safely in the air), I forgot all about it and lost myself in a book.

When I asked Chris Cooke, Executive Travel’s pilot-columnist, about de-icing, he said the pilots are ultimately responsible for being sure it’s adequate: “After de-icing…during precipitation, the first officer is required to go back into the cabin and look out at the wings to assess the coverage.”

Learning this, I felt a little relieved to know checking procedures are in place. (The fact that the first officer on my flight did not come into the cabin, would have concerned me had I learned this prior to my flight, however.) In any case, I obviously made it home safely.

This is not the first time I’ve noticed something awry on a flight. Once I escorted a colleague to her gate and watched her aircraft taxi away with a burst of flames out the back. There was no one to ask about this as I walked to my own gate, so I breathed a sigh of relief when I knew she reached her destination safely. (I subsequently learned this is not an uncommon or unsafe occurrence.) USA Today’s Ask the Captain column covers a plethora of questions readers ask about sounds on flights that concern them. So I’m not alone.

Homeland Security’s campaign “If you see something, say something,” perhaps makes sense in spotting terrorist activity but would be annoying for airlines if passengers did the same. Backseat drivers not welcome! Have you ever observed something unusual on a flight and thought about ringing the call button?