>> reporter: cnn was there in 2008 for a similar covert operation. that time it was tsa testing its own officers. >> can't see anything? >> yep. >> reporter: at the checkpoint the tester is wanted and papddwanded and patted down. the screener missed it. it's not until the tester lifts his shirt up. >> i see it now. >> reporter: the department of homeland security says it "immediately directed tsa to implement a series of actions, sefrlg several of which are now in place". >> is it the technology failing or screeners not following proper pros call? if tsa's equipment is failing and not doing the job, that's a larger systemic issue that tsa needs to address. >> our thanks to rene marsh for that report. now, we want to hear from you. what changes do you want to see at the tsa? tweet ut @theleadcnn or facebook