SINGLE SECTOR AIRLINE TICKETS could be on the way out, according to reports reaching ABTN from the United States. With the security people paranoid, the Transportation Security Administration has taken the view that a one-way ticket is a terrorist tool and is compelling airlines to have their computers flag one-way tickets holders for extra screening. On a recent trip a reader (an ex-airline person), was erroneously issued a series of one-way tickets for what was actually a return trip, including an overnight stay. That caused the reservation system to flag his name and stamp his boarding pass at each stop with ”SSSS” ” the dreaded 'Quad-S' ” which alerts TSA agents to give him a personal ”once over”. This happened four times in a single day and was, to say the least, inconvenient. He is worried now that he may be on some kind of Big Brother terrorist watch list! He suggests that Europeans travelling on one-way tickets might eventually become similarly afflicted.