Even as a half-dozen companies are rushing to get FAA approval for systems that will allow the in-flight use of personal cellphones on business aircraft, other government entities have questioned cellphone use on airliners, citing security concerns. In December last year the Federal Communications Commission (FCC) proposed allowing the use of cellphones on airliners and offered the usual comment period. One of those comments came in the form of a 23-page brief that reflects the concerns of the Department of Justice, FBI and Department of Homeland Security. It emphasized the agencies’ desire to be able to efficiently intercept suspected terrorist communication by onboard cellphone or Internet. The agencies also expressed concern that terrorists might use cellphones to detonate improvised explosive devices remotely. In its comments, the Justice Department suggested that if the FCC decides to permit cellphone use, the agencies should be given the authority to tap airborne cellphone conversations within 10 minutes of the request.