Lasers on track

When businessman Malcolm Higgins heard yet another complaint about leaf sludgeon Britain’s railway lines causing delays, he wondered if he could fix it with a laser. Not being a scientist, or knowing anything about trains, lasers or leaves, he hired help from defence researchers at DERA and the Rutherford Appleton lab. They found that the hard, slippery black sludge could be chipped off the rail by nanosecond pulses of infrared laser light, which heat and rapidly expand the cellulose it contains. Higgins’s company, LaserThor, is now testing a prototype that can clear the track when mounted on service trains travelling at up to 60 kilometres per…