Mildew. A type of fungus or mold that forms on fabric and leather in damp environments. Mildew weakens some materials and if it appears on a parachute canopy, the areas must be cleaned, repaired, or replaced.

Military specification (MIL-SPEC). A specification set by military agencies and used for the procurement of military supplies and equipment.

Minor repair. A repair other than a major repair.

Modification. 1. A change. 2. Often refers to the removing of canopy area to effect steerability and forward glide.

Mouth lock. A device that holds the mouth of the canopy closed until the lines are deployed.

MPH. Miles per hour.

MSL. Mean sea level.

MS. Military Specification under the MS system.

NAS-804. National Aircraft Standards Specifications Number 804; this is the minimum performance standards required by Technical Standard Order, TSO-C23b, for parachute assemblies manufactured under this TSO.

National Airspace Standards (NAS). National Aircraft Standards.

Needle. A small, slender, pointed piece of steel with a hole for thread used for sewing.

Nicopress. A copper sleeve used to join cables to form loops or splices.

Nylon. A synthetic material of protein-like structure derived from coal, air, and water, which is adapted for fashioning into filaments of extreme toughness, strength, and elasticity and used in the manufacture of parachutes.

Opening shock. The decelerating force exerted on the load following that of the snatch force. Caused by the acceleration of the canopy and the air mass associated with it.

Opening time. The time elapsing between the opening of a parachute pack and the opening of the canopy to its fullest extent.

Oscillation. Pendulum-like swinging of the suspended load beneath the inflated canopy; usually the result of trapped air escaping under the lower lateral band.

Outboard. Facing to the outside, such as a ripcord facing to the side of the jumper rather than toward the breastbone.

Overhand knot. A simple knot tied separately in each end of a piece of cord above a square, surgeon’s, or other knot to prevent the end from slipping through the lower knot.