The TSA has banned radio-controlled toys from carry-on luggage - with good reason it seems:
‘In the South Carolina case, the authorities found a 12-minute Arabic-language videotape on the computer of Ahmed Abdellatif Sherif Mohamed, a student at University of South Florida, that had been uploaded to YouTube. In it, a narrator explains how to convert a toy car into a detonator, an affidavit filed in federal court Thursday says.’ - read the whole story from iht.com