I'd like to know the TSA's success record in detecting threats to our safety. I'm not talking about some dude with a knife in his pocket, or a drug dealer with

I'd like to know the TSA's success record in detecting threats to our safety. I'm not talking about some dude with a knife in his pocket, or a drug dealer with a vial of whatever in his underwear. I'm talking about some guy with the intent AND the means to do harm to an airplane or a passenger in an airplane. How many of those type people have the TSA stopped? A Google search returns very little in the way of results, so I'm lacking data in making a decent determination on their success/failure rate. Are we even told about these events, if they occur?