Trains may soon use lasers to clear debris off of tracks

Each autumn, leaves fall to the ground by the billions. Slightly annoying if you have a backyard but really annoying if you run a railroad company. It turns out those leaves are a slippery menace on train tracks. That’s why Dutch Railways is testing a high-energy solution: Train-mounted lasers. In a recent article, New Scientist lays out the seriousness of the fallen leaf problem. Movement grinds the leaves into a “hard Teflon-like residue” that coats the tracks, reducing traction and messing with signaling systems. 

IF THEY won’t budge, zap ’em! Train-mounted lasers are being tested as a way of clearing the path for high-speed trains. What requires such forceful removal? Leaves. Every autumn, fallen leaves are a dangerous problem for railways in much of Europe and North America. Passing trains squash leaves on the track into a hard Teflon-like residue that coats the rails, making it difficult for wheels to grip them. The reduced contact between wheels and track also affects signalling systems that are meant to keep trains from colliding. According to Network Rail in the UK, leaves caused 4.5 million hours of passenger delays in 2013. Last month, Dutch Railways began trials to zap leaves into oblivion with lasers. Angled downwards and fitted just in front of a wheel, the lasers vaporise built-up residue as the train passes. They also dry the rails to prevent new leaves from piling up. This gives trains better traction, allowing faster acceleration and braking.