flexible plastic pipe is reeled onto a reel mounted on a truck and is temporarily laid on a field site by driving the truck along , permitting the flexible pipe to unreel . a brake on the reel puts tension on the flexible pipe as it is being unreeled . to retrieve the flexible pipe , it is cut into segments , each segment being of a shorter length than the total amount of flexible pipe reeled onto the reel . then , each segment is reeled onto the reel with the truck stationary and the reel driven through a transmission from the truck .