Bar tack. A concentrated series of zigzag-like stitches used to reinforce points of stress.

Barometric pressure release. A device of the automatic opening of a free-fall parachute operating on the differences of barometric pressure.

Becket. A piece of tape or webbing sewn to a parachute or pack to form a loop through which a cord or thread may be passed.

Beeswax. A wax, usually mixed 1:1 with paraffin and heated. Webbing is dipped into it to prevent fraying.

Bellyband. A reserve tiedown strap.

Bias construction. Construction where the warp and filler threads of the material are at 45 degrees to the centerline of the gore.

Bias cut. A diagonal cut across a piece of fabric. Canopy fabric may be cut on the bias and assembled so that both warp and fill threads run at a 45 degree angle to the vertical centerline of the gore.

Block construction. An arrangement of the gores such that the warp threads are parallel to the peripheral hem.

Bobbin. A small spool used to hold thread. Commonly found in sewing machines.

Bodkin. A large-eyed needle, flat or round, and usually blunt, used to draw tape, ribbon, elastic, or cord through a loop or hem. Used to pull pack opening bands through containers.

Bolt. A compact package or roll of fabric.

Break tie. Any tie or tacking designed to break under a specified amount of stress.

Breakaway. The jettisoning of the malfunctioned main parachute by activating riser releases and deployment of the reserve parachute; also known as cutaway.

Breakcord. A thread or tape tied between parachute components that is intended to break under the desired load during deployment.

Bridle. A line that attaches the pilot chute to the apex of the canopy or to a sleeve or bag.

Bungees. Pack opening bands.

Burble. The turbulent and unstable airflow behind a falling object, such as a skydiver in free fall.

Cable ripcord. A flexible metal cable 3⁄32" diameter made of 49 strands of stainless steel wire. The cable runs from the ripcord grip to the locking pins. It is housed in a flexible, protective tube.

Calendering. The process where a machine with heated rollers is used to finish fabric. The heat and pressure process lowers permeability by forcing the fibers between each other and flattening them.