at inflation, thus improving the opening characteristics of the canopy. BAND, RETAINING—A rubber band used to hold folded suspension lines in a container or faked lines together. B A R R E L ,  A U T O M A T I C  P U C H U TE RIPCORD RELEASE—That part of an automatic parachute ripcord release that houses the cartridge and piston or spring and piston. BARTACK—A concentrated series of zig-zag stitches used to reinforce points of stress. A bartack should have 28 stitches per half-inch (per MIL-O-81900AS). BEESWAX—A wax, generally with paraffin, that is applied cold or melted to thread to prevent raveling or cloth unknotting and to make thread easier to sew. BIAS CONSTRUCTION—A type of canopy construction in which the canopy cloth is cut and sewn so that the centerline of each gore runs at a 45-degree angle to the warp and filling thread of the canopy cloth. BINDING—A piece of tape or fabric folded over and stitched to a raw edge of cloth to prevent raveling or fraying. BODKIN—A large-eyed, blunt needle instrument for inserting thread, tape, ribbon, or line through a loop, hem, or channel. Used to feed suspension lines through canopy radial seams or to stow suspension line bights in certain parachute container assemblies. BOLT—A package or roll of cloth of varying widths. Also, a measuring term for 40 yards of material. BOTTOM, FALSE—Apiece of cloth sewn to the inside of a pack to retain the frame. It also serves as a base for attaching suspension line hesitater loops. BRAID—A narrow band of interlaced strands. BREATHING—The pulsating action of the parachute canopy when fully inflated. BUNCHED STITCHING—Stitches too close or more stitches per inch than required. BURL—A knot or lump in thread or cloth. BURNS, FRICTION—A hard spot on the suspension line caused by two lines rubbing together at high speeds, generally off-color and brittle. C—Abbreviation for Celsius. CABLE, ARMING, AUTOMATIC PARA- CHUTE RIPCORD RELEASE—A cable that, when attached to the ejection seat, lap belt, or other designated point, arms the automatic parachute ripcord release at seat/man separation. CABLE, POWER, AUTOMATIC PARA- CHUTE RIPCORD RELEASE—A cable covered by a housing, which transmits the force from the automatic ripcord release assembly to the ripcord cable. CABLE, RIPCORD—A flexible cable joining the locking pins and ripcord handle. CANOPY—The main supporting surface of a parachute that, when opened, reduces the rate of descent. It is usually made of nylon and includes a framework of cords, called suspension lines, from which the load is suspended. CANOPY, CONICAL—A canopy con- structed in the shape of a cone. See also CANOPY. CANOPY, EXTENDED SKIRT—A canopy that has a flat circular center or disk when spread out. See also CANOPY. CANOPY, FLAT CIRCULAR—A canopy that has the shape of a flat circle or disk when spread out. See also CANOPY. CANOPY, GUIDE SURFACE—A mush- room-shaped canopy in which alternate roof panels are extended to provide guide surfaces. See also CANOPY. CANOPY, HEM-RIGGED—A canopy that the suspension lines are attached to the skirt hem and do not pass over the drag-producing surface; for example, the 26-foot conical canopy. See also CANOPY. CANOPY, RIBBON—A canopy composed of concentric cloth ribbons, supported by radial ribbons and tapes. See also CANOPY. AI-2