Well that's a whole different thing. If you were arrested, charged, but it was dismissed then that does not affect you with the TSA at all. You are in the clear.

The airlines might see something in the FBI database, but unless they ask if you have ever been arrested you should be OK. They may not see any details of the charge, but they may see that it happened.

Sorry about the confusion, you gave me the impression that you had a conviction.

Worst case, an airline asks about arrests. In that case you should probably be honest, but the airline will probably not have access to any details to verify what you tell them.