at doing vs flying

Some examples from the web:

• Look, you are really great at doing hair.
• I'm great at doing voices.
• We all know that we are very good at talking about it and we are equally bad at doing anything material to address the problem.
• This is what the US and the EU are experts at doing.
• But our attempts at doing this are crude and blundering compared to the fine-grained specificity of the parasites.
• And you know how good I am at doing what I'm told.
• He's so bad at doing the right thing.
• They will do whatever it takes to protect the Federation and wouldn't blink at doing this.
• I find that incomprehensible because it is an amendment which goes to the very heart of integrating environmental considerations into other policy areas, something that the European Investment Bank has not been successful at doing.
• You know those people who are just really terrible at doing accents?
• Come on, we have finally succeeded at doing the thing that we have talked about since we were little kids.
• And still, if I look ahead at doing fasting,
• I'm not as good as you are at doing what I'm told.
• Due to the fact that the several "processing stations" are not in logical, physical sequence - and often far away the one from the other - and most often busy at doing something else...
• They become masters at doing it.
• A failed and feeble attempt at doing the right thing.
• She's an expert at doing nothing.
• And of course, math is very powerful at doing that.
• His first effort at doing so had already failed.
• And now we had a shot at doing these movies.

Some examples from the web:

• Which implies an entirely different type of flying object.
• And inform a Fly-Eye flying camera.
• Never walked onto a flying base before.
• One, the R.A.F. Is not a flying circus.
• Now I'm a flying, talking donkey.
• Were found also plans for a flying saucer made by a person who worked for Mussolini, probably following studies on the recovered flying saucer in 1933.
• And sparks start flying inside too.
• Because flying is like adrenaline to tense pilots.
• Means counting on a bunch of civvies flying close formation.
• Nobody's flying these planes today.
• Joss Whedon's vision keeps flying.
• Maybe when kids started flying off cars.
• The resolution passes with flying colors.
• Amelia Earhart demonstrates her flying prowess and adventurous spirit.
• Seen more people die driving than flying.
• I have some questions about flying machines.
• Ground flying trainers and parts thereof, n.e.s.
• Because flying through here is insanity.
• I should be flying this mission.
• Build a great building set Italian flying boat.