A jumper experienced broken suspension lines on his new main parachute that required him to cut away and deploy his reserve. Later, when investigators inspected the main parachute, they determined that tension knots, which most likely developed in the jumper’s semi-stowless deployment bag, caused one line to saw through the other lines. Jumpers must carefully fold suspension lines into the pouch of a semi-stowless bag to allow the lines to pull free in an orderly manner.