Moisture + freezing can cause Kevlar fibers to stick together. The load is then concentrated on a few fibers which break.
If this relatively exceptional situation occurs several times during a professional tandem season in a ski resort, the minimum resistance required can be reached in less than a year, especially with intensive use (250 flights per year for example) and with acrobatic maneuvers!
If your lines are made of Kevlar and you are flying in very cold weather with lines that may have been wet, have their resistance checked !
