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Skydiving terms glossary
A
- AAD: Automatic Activation Device. A device that senses rate of descent and altitude and which will attempts to mechanically activate the reserve parachute if the skydiver passes below a set altitude at a high rate of descent.
- A/C: Abbreviation for aircraft.
- A LICENSE: The first level your USPA license which signifies that a skydiver has advanced beyond the novice phase. Persons holding a USPA A License are able to jumpmaster themselves, perform basic relative work jumps, water jumps and pack their own main parachute.
- ACCELERATED FREEFALL (AFF): USPA: Harness-hold freefall skydiving student training discipline developed under Ken Coleman and adopted by USPA. AFF-rated USPA Instructors accompany the student in freefall during the initial training jumps.
- ACCELERATED FREEFALL CERTIFICATION COURSE AND TRAINING CAMP: A course registered with and authorized by USPA HQ to train, qualify and test candidates for Jumpmaster and Instructor ratings in the Accelerated Freefall method of student instruction. Also known as AFF CC.
- ACCELERATED FREEFALL GRADUATE STUDENT: A novice skydiver who has successfully completed the training of the Accelerated Freefall method but has not yet obtained a USPA license.
- ACCELERATED FREEFALL SEMINAR: A gathering of USPA Accelerated Freefall rating holders to exchange, discuss and introduce new ideas to develop, improve or assure the quality of techniques and instruction used in the Accelerated Freefall method of instruction.
- ACCELERATED FREEFALL STUDENT: A skydiver trainee being trained by the Accelerated Freefall method who has not yet graduated from AFF Level 7.
- ACCURACY: Also known as Precision Landing, this is a competition discipline in which the skydiver attempts to land on an established target. At the National level the target is 3 cm in diameter, about the size of a quarter. Accuracy landings of various difficulty, from 20 meters to 2 meters, are required for USPA licenses. See the SIM for details.
- AFF: See ACCELERATED FREEFALL.
- AGL: Above ground level.
- AIRCRAFT: Any machine or device, including airplanes, helicopters, gliders, balloons, etc. capable of atmospheric flight. Parachutes are not considered aircraft.
- AIRSPEED: The speed of a flying object through the air, commonly used in reference to aircraft or canopies.
- ALTERATIONS: Changes to the original configuration, such as removal of a gore, installation of an AAD or the addition of a deployment device. Any change or modification to any part of the parachute assembly from its original manufacturer. s specifications.
- ALTIMETER: A device indicating altitude.
- ANGLE OF ATTACK: The angle at which the wing is presented to the apparent wind. With square parachutes this changes when the brakes are applied.
- ANGLE OF INCIDENCE: The angle at which a canopy is trimmed to glide through the air.
- AOD: Old name for AAD.
- APA: Army Parachute Association, affiliated to the BPA, based at Netheravon.
- APPARENT WIND: The wind perceived by an observer. See relative wind.
- APPROVED: An item for which the FAA has issued approval documents. 1. Approval may be in the form of a TSO, which is stamped on the article, by a military designation such as NAF, AAF or AN contract number, which is also stamped on the article, or by an STC or a Field Approval (Form 337). 2. Any alteration to an approved item will void the approval unless it is done in accordance with a specific alteration approval issued by the FAA.
- APPROPRIATELY RATED: adj. Refers to a USPA Instructor or Instructor Examiner rated in the method-specific instructional discipline necessary to perform a particular task in accordance with the BSRs.
- ARCH: n. Position skydivers use to orient the front of their torso to the relative wind. Described, it is hips forward with back arched; legs extended to 45 degrees, toes pointed; knees at shoulder width; arms bent 90-120 degrees at the shoulders and elbows and relaxed; head up.
- ARTISTIC EVENTS: Skydiving competition events that include freeflying, freestyle skydiving, and skysurfing.
- AS 8015A: Aerospace Standard 8015A defines the tests and minimum safety and performance standards which must be met for a parachute to receive approval under TSO C-23c. Adopted in 1984 to supersede NAS 804.
- ASP: Accelerated Skydiving Program. This usually includes two tandem jumps and an enhanced version of the AFF course.
- ASTRA: An AAD made by FXC Corporation.
- ASPECT RATIO: The ratio of a canopys width (side to side) to breadth (front to back). Seven cell canopies typically have an aspect ratio of about 2.2 to one, while nine cell canopies are usually between 2.8 and 3.0 to one.
- ATC: Air Traffic Control
- AUDIBLE ALTIMETER: An alarm used by skydivers to alert them about reaching one or more pre-set altitudes.
- AUXILIARY PARACHUTE: Another term for the reserve or emergency parachute used on intentional jumps.
- AUTOMATIC ACTIVATION DEVICE (AAD): A self-contained device attached to the parachute which automatically activates the parachute container opening sequence at a preset altitude, time, percentage of terminal velocity or combination thereof.
B
- B-12(s): Clip hardware sometimes used for leg-strap attachment on a parachute harness. Refers generally to the MS 22044 hardware originally used on the U.S. Army B-12 parachute assembly.
- B LICENSE: The second level your USPA license. Persons holding a USPA B License are able to jumpmaster themselves, pack their own main parachute, perform water, night and relative work jumps and participate in record attempts.
- BACKSLIDE: To move backward in freefall relative to a neutral reference. Usually unintentional and undesirable, caused by poor body position.
- BAG: The deployment bag in which the canopy is packed.
- BAG LOCK: A malfunction of a freefall system where lines have deployed but canopy is still trapped in bag.
- BASE: n. 1. When building a freefall or canopy formation, the initial target individual or group of people to which the others fly. 2. BASE (LEG): n. The portion of the three-legged landing pattern where the jumper flies across the direction of the wind downwind of the landing area before turning for final approach into the wind toward the target..
- B.A.S.E. JUMP: A jump made from a fixed object rather than an aircraft. BASE is an acronym for building, antennae, spans (bridges) and earth (cliff).
- BASIC SAFETY REQUIREMENTS (BSR): Minimum standards generally agreed upon as the accepted standard for safe skydiving activities. Published by USPA.
- BCPA: British Collegiate Parachute Association- A group run by and for college students, associated with the BPA. Runs regional and annual competitions for BPA members still undertaking education.
- BEECH: Short for Beechcraft, an aircraft manufacturer. Usually used in reference to a Beech D-18, a.k.a. Twin Beech. At one time these were common skydiving planes, but they are becoming obsolete.
- BELLY FLYING: Freefalling in a belly to earth position i.e. formation skydiving.
- BI: Basic Instructor
- BIC (Basic instructors course): Attended in an effort to gain a sufficient level of proficiency with reference to teaching.
- BLADE RUNNING: Swooping under canopy through a series of wind blades along the ground.
- ** BOARD OF DIRECTORS (BOD). USPA**: Those representatives elected by the general members of USPA every two years as set forth in the USPA By-Laws; authorized by the by-laws to have general charge and control of the affairs, funds, and property of the organization and to carry out the objectives of the organization and its by-laws; elects officers from among current USPA Board members. The USPA Board of Directors consists of: 1. National Directors-those directors elected at large by the general membership; 2. Regional Directors-those Directors of a specified geographical area, elected by and responsible for representing the interests of the skydivers in a USPA Region; and 3. An ex officio member representing the National Aeronautical Association.
- BOC (Bottom of Container): Refers to the location of the pilot chute. An increasingly common position for main deployment devices, as opposed to belly or leg mounted.
- BODY POSITION: Ones freefall body posture. Variations in body position are what make a wide range of freefall maneuvers possible.
- BOOGIE: A gathering of skydivers, usually focused on fun rather than competition. Big drop zones host several boogies a year, often on long holiday weekends.
- BOOTIES: Jumpsuit 'feet' which hook over the front of the shoe.
- BOUNCE: To land at unsurvivable speed. Also to frap, or go in.
- BOX MAN: A neutral, face to earth body position in which the arms form right angles at shoulder and elbow, and the legs are spread at about 45 degrees from the long axis and bent 45 degrees at the knees. Generally considered the ideal position for Formation Skydiving.
- BPA (British Parachute Association): The governing body of sport for parachutists within the BPA, run by an elected Council of 15 sport parachutists, with a number of full-time employees fulfilling technical and administrative tasks.
- BRAKED TURN: A turn under an open parachute canopy made by using the steering toggles to slow the forward speed of the canopy and then allow one side to fly slightly faster to change heading. Used to reduce altitude loss in a turn.
- BRAKES: The brake lines of the canopy are synonymous with steering lines. Used together, they slow the parachute. Used independently they result in a turn.
- BREAK AWAY: See CUT AWAY.
- BRAKES: The brake lines of the canopy are synonymous with steering lines. Used together, they slow the parachute. Used independently they result in a turn.
- BREAKAWAY HANDLE: See CUTAWAY HANDLE.
- BREAKOFF: n. Procedure in group skydiving where jumpers cease group activity and separate. In freefall, jumpers begin to track at a predetermined altitude for a clear area to open safely; jumpers building canopy formations break off at a predetermined altitude to gain safe separation and allow jumpers to prepare for a landing approach.
- BREAK ALTITUDE: 1. RWA predetermined altitude at which all jumpers turn 180° from the center of the formation and track in order to have enough airspace to safely open their parachutes. 2. CRW The altitude after which no more incoming canopies are allowed to dock. Also known as the Hard Deck.
- BRIDLE: The thin webbing strap from the pilot chute to the top of the canopy. Part of the deployment system which consists of pilot chute, bag and bridle.
- BSR: Basic Safety Requirements. BSRs are USPA guidelines. They do not have force of law but are generally regarded as excellent minimum safety standards.
- BURBLE: The area of turbulence behind an object going through the air, whether a person in freefall or a canopy in flight.
- BUM SPOT: An error of judgement by the jumpmaster, in which you have been despatched at a point at which you will probably find it impossible to get back to the PLA.
- BUNGEE: Rubber band used for stowing lines.
C
- CAA: Civil Aviation Authority, the body responsible for air standards, safety and operations in UK airspace.
- CATEGORY: A stage of progression from 1-8, with a specific set of guidelines for achievement, laid down by the STC. Followed by all students undertaking training at BPA Affiliated Parachute Clubs. Category 1-8 jumpers are classified as student parachutists.
- C LICENSE: The third level your USPA license. Persons holding a USPA C License are able to jumpmaster other licensed skydivers, pack their own main parachute, participate in certain USPA competitions and in record attempts, perform relative work, night, and water jumps and are eligible for the USPA Jumpmaster rating.
- CALL: The time remaining until you are to board the aircraft. For example, a fifteen minute call means you will board in fifteen minutes.
- CANOPY: The construction of a fabric or drag surface of a parachute which includes the suspension lines from which the load or person is suspended.
- CANOPY FORMATION (CF); CANOPY RELATIVE WORK; (CRW): n. 1. The intentional maneuvering of two or more open parachute canopies in proximity to or in contact with one another during descent. 2. The FAI competition discipline involving the building of canopy formations.
- CANOPY RELEASE: A device which allows immediate separation of the parachute canopy and risers from the harness.
- CASCADE: The point where two or more suspension lines of a canopy join into one. Cascading the suspension lines results in reduced bulk and drag.
- CCI: Club (or Centre) Chief Instructor, Advanced instructor (or Advanced Instructor/Examiner) nominated as the person in charge of a parachute operation.
- CELL: Square canopies are made up of pressurized cells, usually seven or nine. Each cell consists of a load bearing rib at each side to which the suspension lines are attached. A third, non load bearing rib runs down the middle of the cell. The cell is pressurized through the open mouth at the front and also through cross ports in the ribs. Adjacent cells share load bearing ribs.
- CENTER POINT: The point around which movement takes place. In an individual the center point is considered to be in the middle of the torso. In a group, it is the point that the formation centers around.
- CERTIFICATED: Refers to FAA-approved parachutes such as commercially manufactured parachutes and government surplus models which were manufactured under military contract. The FAA uses this term to describe any product it has approved as airworthy and to describe persons it has approved for various functions such as pilot, rigger, etc.
- CESSNA: An aircraft manufacturer. Single engined Cessnas such as 180s, 182s and 206s are the workhorse of smaller drop zones, carrying four to six jumpers.
- CF (Canopy Formations): Formation Work with 2 or more square canopies. Used to be known as CRW (Canopy Relative Work).
- CHECK OF THREES: Pre-jump equipment self-check performed in the aircraft__: check three-ring release system (and RSL) for correct assembly; check three points of harness attachment for snap assembly or correct routing and adjustment; check three operation handles--main activation, cutaway, reserve--in place.
- CHORD: n. The longest dimension from the front to the back of a wing at any given point along the span.
- CHUTE ASSIS: French for sit flying, or freefalling with one's seat presented to the relative wind.
- CLASSICS: Style and accuracy.
- CLEARED: adj. Refers to a student who has received a signature from a USPA Instructor to advance.
- CLIMBOUT: n. The act of a jumper positioning himself or herself in or near the door or on protuberances or structures outside the aircraft to prepare for launch, usually with a group.
- CLOSING LOOP: A lace that when threaded through eyelets in the parachute container flaps and locked with a closing pin, keeps the parachute contained until activation.
- COACH: A skydiver with some formal training in the art of instructing freefall technique.
- COACH, USPA: n. The entry-level USPA instructional rating whose holder may teach the general (non-method-specific sections of the first-jump course) and conduct group freefall skills training and jumps with students, all under the supervision of a USPA Instructor.
- COLLAPSIBLE PILOT CHUTE: A hand-deployed pilot chute that automatically collapses after deployment.
- COLLAPSIBLE SLIDER: A slider rigged so the jumper can compress or wrap it to reduce drag (see also SLIDER).
- CONTAINER: The portion of the assembly that is used to store the folded parachute canopy. Not to be confused with the term pack. See PACK.
- CRABBING: A canopy is crabbing when it is flown at an angle sideways to the ambient wind, resulting in a path across the ground that is sideways as well as forwards.
- CREEP: To creep is to practice formation skydiving sequences while laying prone on a creeper.
- CREEPER: A board equipped with wheels on which a skydiver lays to simulate freefall maneuvers.
- CReW: Canopy Relative Work, old term for CF.
- CORK: v. During high-speed group freefall maneuvers, to lose control and decelerate rapidly.
- CROSS BRACED: (adj.) Refers to a canopy designed with longitudinal trussing between the vertical ribs to flatten and stiffen the wing in flight.
- CROSS CONNECTORS: Straps attached to the risers. For CRW they should be from front to rear only, to prevent the docked jumper from sliding back up the lines. Especially important for plane formations. Also used with some RSL systems and attached from side to side to prevent premature reserve deployment if only one riser is released.
- CROSS PORTS: Vents or holes cut in ram-air canopy ribs of a cell that allow air flow from one cell to another to ensure even pressurization of the canopy.
- CROSSWIND: Perpendicular to the direction of the wind.
- CRW (Canopy Relative Work): now officially known as Canopy Formations (CF). CRW involves flying open canopies in close formation, where the pilots actually take grips on each other's parachutes.
- CRW BASE-PIN: The initial docking of two canopies on which the rest of a CRW formation is built.
- CURRENT: To "be current" is to have jumped recently enough to retain proficiency in the sport. Uncurrent skydivers, depending on their experience, must be supervised to some degree when they resume jumping. See the SIM.
- CUT: Command given to the pilot to slow the aircraft speed for exit.
- CUTAWAY: Separating or releasing of the main canopy and risers from the harness by activating riser releases. A procedure for handling a malfunctioned main canopy that must be followed by deployment of the reserve. Also called BREAKAWAY.
- CUTAWAY HANDLE: A handle, usually mounted on the harness, used to release both main risers. Sometimes referred to as a single point release.
- CYPRES: A type of AAD. Made by AirTech of Germany, this is the most common type of AAD and the first modern design to be widely adopted by expert skydivers.
D
- D LICENSE: The fourth and highest USPA license. Persons holding a USPA D License are able to jumpmaster other licensed skydivers, pack their own main parachute, participate in all USPA competitions and record attempts, perform relative work, night, water and certain demonstration jumps, are eligible for all USPA ratings and for appointment as a Safety & Training Advisor.
- DACRON: A common construction material for canopy suspension lines. Dacron lines are thicker and softer than so called "microlines".
- DATA CARD: Every parachute carries a data card with information on the reserve parachute, including type, last date packed, owner, serial number, etc.
- DC-3: A type of aircraft, the Douglas DC-3 is a large, twin engined airplane capable of carrying over 40 jumpers. Like the Twin Beech, DC-3s are being rapidly replaced by more modern turbine engined aircraft.
- DE-ARCH: To flatten out or reverse one's body position from the normal arched box man. A de-arch results in a slower fall rate than an arch.
- DEAD SPIDER: Slang for de-arch.
- DEBRIEF: Post skydive analysis.
- DECISION ALTITUDE: The altitude at which a skydiver is trained to begin execution of emergency procedures. Usually 2,500 feet AGL for students, and 1,800 feet for expert skydivers.
- DEPLOYMENT SYSTEM: The components of the parachute that control deployment of the canopy. Includes pilot chute, bridle and bag.
- DELAY: The period of time in freefall.
- DELAYED OPENING: Obsolete, See FREEFALL.
- DELTA POSITION: A modified stable freefall position made by a skydiver drawing his arms back near his sides, which results in a head-low attitude. This position increases rate of descent and horizontal movement.
- DEMO or DEMO JUMP: A jump made away from an established drop zone for the benefit of spectators. Also an exhibition or display jump.
- DENSITY ALTITUDE: An expression of air density relative to standard atmospheric pressure at sea level. The pilot calculates pressure altitude and temperature and compares the result with an equivalent altitude MSL at standard temperature.
- DEPLOYMENT: That portion of a parachute. s operation occurring from the moment of container opening (or pilot chute release when using a hand-deployed pilot chute) to the instant the suspension lines are fully stretched out but prior to the inflation of the canopy.
- DEPLOYMENT BAG: A device which contains (holds) a parachute canopy until the suspension lines have deployed. Bag may or may not provide a place to stow suspension lines. A pilot chute lifts a deployment bag away from a parachute container, causing the suspension lines to be extended before the canopy emerges from the deployment bag.
- DEPLOYMENT DEVICE: A sleeve, bag or other device used to control the opening sequence of a parachute.
- DIAPER: A type of deployment device consisting of a fabric panel attached near the lower part of a canopy which prevents canopy inflation until full line stretch. Used frequently with round parachutes to reduce opening shock and malfunctions.
- DIRECT SUPERVISION: The person providing direct supervision must be physically present during instruction, packing, or other activity being supervised, standing by to assist if necessary. The supervisor must take responsibility for the actions of those being supervised.
- DIRT DIVE: To rehearse a skydive on the ground.
- DIVE: One of the methods of exiting the aircraft and can be short for skydive.
- DIVE BLOCKS: Hand grips (not loops) on the front and/or rear risers to facilitate diving and controlling the canopy.
- DIVE FLOATER: A dive floater is a skydiver who is inside the airplane in the exit line up, but leaving prior to the base. This configuration only occurs on large formations.
- DIVE LOOPS: Many advanced skydivers have loops or "blocks" on their front risers to make it easy to grip the front risers for steering purposes. Also called front riser loops.
- DIVER: Anyone diving out of the plane during a formation skydiving exit.
- DIVER EXIT: Leaving an aircraft by diving out of the aircraft door; made without positioning or bracing to achieve a stable entry into the airstream.
- DOCK: Take up a grip on a freefall formation or the linking of one canopy to another.
- DOOR EXIT: Leaving an aircraft by diving out of the aircraft door; made without positioning or bracing to achieve a stable position.
- DOOR JAM: To practice an exit in the aircraft door of a mock up of it prior to the skydive.
- DOWN PLANE: A CRW formation with two canopies, both pointed toward the ground. This can also occur to a single skydiver with both main and reserve deployed.
- DOWNWIND: 1. adj. The direction toward which the air is moving. 2. adv. or adj. positioned farther along the wind's path. 3. n. (jar.) a downwind-facing landing.
- DOWNWIND LEG: The portion of the landing approach flown with the wind blowing from behind the jumper.
- DROGUE: A trailing drag device used to retard the movement of an object through the air, used in skydiving to regulate the fall rate of tandem skydivers.
- DROGUEFALL: In tandem skydiving, the portion of the descent where a drogue has been deployed between freefall and main parachute deployment..
- DP: Dummy-pull (also known as DRCP). Training stage, as part of preparation for Free-fall.
- DROP ZONE (DZ): Also know as DZ. A specified area into which skydivers intend to land. Also refers to a commercial parachute center.
- DUAL ASSEMBLY: Refers to a two-canopy parachute system, includes the main and reserve canopies and all other components.
- DUMMY RIPCORD PULL (DRCP): See PRACTICE RIPCORD PULL.
- DUMP: Deploy Canopy.
- DUST DEVIL: A mini wind hurricane that can collapse a parachute.
- DYNAMIC STALL: n. An action that occurs following the flare of a ram-air canopy, where the load (jumper) has swung forward under the canopy from the braking action and begins to swing back.
- DYTTER: A brand of audible altimeter.
- DZ: Drop Zone. A notified portion of airspace within which skydives/ parachute descents are made.
E
- EMERGENCY PARACHUTE: A certificated parachute which is intended for emergency use.
- ELLIPTICAL: A wing shape characterized by a tapering leading and trailing edge so that the middle of the canopy is wider, front to back, than the ends. This configuration is typical of many high performance canopies.
- END CELL: The cells furthest out on a canopy on either side.
- END CELL CLOSURE: Deflated end cell. Routine opening problem, usually correctable.
- EP: 1) Exit Point. Point over the ground determined as the release point from the aircraft, such that freefall drift, throw-forward and other factors cause you to arrive at the opening point at the right height. 2) Emergency procedures – procedures taken when a malfunction occurs.
- EXHIBITION JUMP: See DEMO JUMP.
- EXIT: Leave the aircraft and enter freefall.
- EXIT POINT: That point on the ground over which the skydiver jumps from the aircraft.
- EXIT WEIGHT: The total weight of the jumper and all equipment and clothing.
- EXTRAORDINARY SKYDIVE: n. Night jump, water jump, jump from above 15,000 feet MSL, exhibition jump, pre-planned cutaway jump, and other jumps requiring special equipment and procedures that might be unfamiliar to most jumpers.
F
- F-111: A fabric common in mid range canopies, F-111 is slightly permeable to air and wears faster than zero-p fabric. Pronounced "F one eleven".
- FAA: The Federal Aviation Administration is the agency of the US government that regulates aviation activity, including skydiving.
- FAI: Federation Aeronautique International. The international organization governing air sports.
- FARs: Federal Aviation Regulations, the laws governing aviation.
- FALL RATE: The speed at which a skydiver falls. Matching fall rate is essential to successful formation skydiving. This is done with jumpsuits, weights and body position.
- FARMER McNASTY: Unenlightened term for a disenchanted drop zone neighbor with whom communications with jumpers are strained or have broken down.
- FEDERAL AVIATION ADMINISTRATION (FAA): An agency of the U.S. Department of Transportation whose primary function and responsibility is to control the nation. s air traffic, including the certification of all civil aircraft and accessories, licensing of all civil pilots, mechanics and riggers and administration of the Federal Aid to Airports Program.
- FEDERATION AERONAUTIQUE INTERNATIONALE (FAI): An international organization which governs all aviation sports, certifies all official aviation and space records and governs official international competitions. Operates through a non-profit National Aero Club in each country.
- FEDERAL AVIATION REGULATIONS (FARs): The parts of the Code of Federal Regulations that apply to aviation.
- FIELD PACKING: The temporary stowing of a parachute in the container after a jump, so that it is more easily transported.
- FINAL APPROACH: The final portion of flight before a jumper or aircraft lands.
- FINGER TRAP: A method of installing a loop in a brake line without producing rough spots on the lines, the finger trap is accomplished by sliding one line into the other. The loop serves as a method of setting brakes in the desired position for the parachutes deployment.
- FLARE: 1. v. (Under canopy**: To convert the downward speed of a parachute momentarily into lift. 2. v. In freefall**: To decelerate prior to approaching a formation. 3. n. The act of flaring. 4. n. A membrane used to distribute the load of a parachute at the line attachment points of some canopies.
- FLAT DELTA: Freefall position with the body on one plane, legs extended and arms swept back, used as a starting or intermediate position when developing a track.
- FLAT LINE: Continuous warning tone from audible altimeter at about 1500 to 1600 ft meaning act now.
- FLAT FLYER: FS jumper.
- FLOATER: Skydivers who leave the airplane before the base are called floaters since they must use a slow fall rate to get up to the base. Floating also refers to an exit position outside the airplane.
- FOREIGN PARACHUTIST: A parachutist who is neither a U.S. citizen nor a resident alien and is participating in parachute operations within the United States using parachute equipment not manufactured in the United States. (FAR 105 definition).
- FORMATION: 1) A freefall skydiving formation of more than one jumper. 2) A flight of more than one jump plane.
- FORMATION SKYDIVING (Relative Work): 1. Aerial maneuvers by two or more freefalling skydivers with each other, usually to form geometric formations. 2. Competition discipline of flat-flying.
- FREEFALL: The portion of a parachute jump or drop between aircraft exit and parachute deployment in which the parachute is activated manually by the parachutist at the parachutist's discretion or automatically, or, in the case of an object, is activated automatically. (FAR 105 definition).
- FREE FLY: v. To exit unlinked with other jumpers.
- FREEFLYING: n. 1. An unrestricted freefall discipline characterized by varied presentations to the relative wind. (see also SIT FLYING and HEAD DOWN). 2. n. The competition event of freeflying.
- FREESTYLE: 1. A solo freefall discipline that involves choreographed multi-orientation static and dynamic maneuvers. 2. The competition event of freestyle performed as part of a team with a camera flyer (freestyle skydiving).
- FULL FLIGHT: The stabilized state of hands-off canopy flight under an open and fully functioning parachute.
- FS (Formation Skydiving): Skydiving discipline in which two or more skydivers join together in different predetermined sequences or positions to make different freefall formations. (Previously known as relative work).
- FRAP: To make a mistake and die.
- FROMMEL: What happens when a skydive formation self destructs.
- FUNNEL: A funnel occurs when one or more skydivers find themselves in an unstable body position and end up in a skydivers burble. The resulting loss of stability for the other skydivers usually causes the formation to break up.
- FXC: A company manufacturing AADs. One FXC design is common on students but considered by many to be unsuitable for expert skydivers. A new FXC design, the ASTRA, went on the market in the spring of 1996 and is relatively unknown.
G
- GATW: Acronym often used in student logbooks, meaning "Good All The Way".
- GLIDE: n., v. The combined horizontal and vertical movement of a descending canopy.
- GLIDE ANGLE: The trajectory of a wing expressed as the distance forward to altitude lost, e.g., a 3:1 glide angle means the wing will travel three feet forward for every foot downward.
- GLIDE RATIO: The distance a canopy flies forward compared to down. A canopy with a 3:1 glide ratio flies three feet forward for every foot of vertical descent.
- GO-AROUND: n. An in-flight operation where the aircraft circles at jump altitude.
- GO TOGGLES: A non-locking front riser pulley system for mechanical advantage used during CRW.
- GOVERNANCE MANUAL, USPA: The official bound collection of the USPA Constitution and By-Laws.
- GPS: Global Positioning System. By picking up signals from satellites, a GPS receiver can tell the user position over the ground. Used in skydiving aircraft to spot the exit.
- GRIPS: Using the hands to hold onto another skydiver in freefall or during the aircraft exits. In formation skydiving, the formations are scored as complete when every skydiver has taken the correct grips.
- GRIPPERS: Hand holds built onto formation skydiving jumpsuits to make it easier to take grips.
- GROUND SPEED: The speed of an airplane or skydiver over the ground, as opposed to through the air.
- GROUNDRUSH: The illusion of the ground appearing to accelerate towards you.
H
- HACKY: 1) Handle of pilot chute shaped like a small hacksack. 2) Game in which a group attempt to keep a small hacksack (beanbag) in the air for as long as possible.
- HALF SERIES: A succession of manoeuvres, two alternate turns and a back-loop.
- HAND-DEPLOYED PILOT CHUTE or HAND DEPLOY: To activate the parachute by manually deploying the pilot chute as opposed to pulling a ripcord. See THROW OUT.
- HARD DECK: CRW The altitude after which no more incoming canopies are allowed to dock and the formation will break or start a Starburst.
- HARNESS: An arrangement of nylon webbing which is designed to conform to the shape of the load to be carried in order to secure it properly, so that the opening force and the weight of the load during descent are evenly distributed. The harness connects the wearer to the canopy through the risers.
- HARNESS HOLD: A skydiving training discipline where a student is trained for independent, solo freefall but is accompanied by at least one USPA AFF Instructor until meeting the requirements in the BSRs for self-supervision in freefall. On the initial jumps, the AFF Instructor(s) assist the student on exit via a harness grip.
- HEAD DOWN: adj., adv. Inverted vertical or nearly vertical freeflying orientation.
- HEADING: The direction an aircraft, skydiver, or parachute is facing. The ability to recognize and maintain heading is crucial to jumping with others successfully. "On" or "off" heading are terms commonly used to describe exits and deployments.
- HOLDING: When a parachute is flying directly into the ambient wind, it is said holding. See running and crabbing.
- HOOK KNIFE: A knife with a blade shaped like a hook. Sometimes used to cut lines in an entanglement.
- HOOK TURN: A sudden turn close to the ground (90 degrees or more) used to build up speed for a spectacular turf surf and gentle landing. When misjudged can result in smashed bones and a lengthy stay in the hospital. Because of the high risk associated with this maneuver, hook turns have an unfavorable connotation.
- HOOKER HARNESS: A single-point aircraft passenger restraint system that integrates with a parachute harness. Designed by Jack Hooker.
- HOP & POP: Slang for a very short freefall delay.
- HORSESHOE: n. A partial parachute malfunction where part of the deployed parachute is entangled with the jumper or his or her equipment.
- HOT FUEL: Hot fuel. When the airplane does not shut down during fueling. Do not board the aircraft while fueling is in progress.
- HOUSING CLAMP STIFFENER: A metal plate sewn to the top flap of a parachute container used to hold the ripcord cable housing in place and give rigidity to the housing.
I
- IAD: see Instructor Assisted Deployment.
- IN DATE: A reserve packed within the previous 120 days is said to be "in date". If more than 120 days have elapsed since the reserve was packed it is "out of date" and illegal to use.
- INSTRUCTOR, USPA: The holder of a USPA Instructor rating qualified in one or more of four methods of instruction: USPA Accelerated Freefall, instructor-assisted deployment, static line, or tandem. The mid level of the USPA instructional rating hierarchy. A USPA Instructor may train and certify a student for the USPA A License, supervise USPA Coaches, and is eligible for appointment as USPA Safety & Training Advisor.
- INSTRUCTOR-ASSISTED DEPLOYMENT (IAD): A method of passive deployment used for training skydiving students making their initial jumps. A USPA IAD Instructor controls a hand-deployed pilot chute while a student moves into position and jumps, at which point the instructor releases the pilot chute. The student is never connected to the jump plane.
- INSTRUCTOR CERTIFICATION COURSE (ICC): A course registered with and authorized by USPA Headquarters to train, qualify and test applicants for the USPA Instructor rating. May be conducted by an Instructor/Examiner or an S&TA with an Instructor rating.
- INSTRUCTOR RATING COURSE, USPA: A course registered with USPA Headquarters to train, qualify, and test applicants for the USPA Instructor rating.
- INSTRUCTOR EXAMINER (I/E), USPA: The highest level of the instructional rating program. An I/E is an experienced USPA Instructor who has met additional proficiency requirements and passed a series of written examinations on a wide variety of skydiving related subjects. An I/E has all of the privileges of a USPA Safety & Training Advisor.
- INSTRUCTIONAL RATING MANUAL (IRM), USPA: The manual containing the collected documents and references required to conduct any course for USPA Coach or USPA Instructor ratings.
- IPC: The International Parachuting Commission oversees sport parachuting. It is a committee of the FAI.
J
- JM: Jumpmaster, an experienced Skydiver, or Instructor, responsible to the CCI and pilot for the parachutists on each lift.
- JUDGE: The official who evaluates a competitor. s performance. USPA issues judge ratings at both the conference and national levels. The FAI issues a rating for internationally recognized judges.
- JUMP ALTITUDE: Actual altitude of an aircraft above the ground at the time a skydiver exits.
- JUMP RUN: The flight of the aircraft prior to exit, usually flown from the target to the exit point.
- JUMPSUIT: A cover all type garment designed for specific skydiving applications such as FS, freestyle or accuracy.
- JUMPMASTER (JM): n. 1. A skydiver, typically a senior jumper or instructional rating holder, who coordinates boarding and exit order, jump flight procedures, spotting, and emergency operations with the pilot. 2. v. To dispatch jumpers. 3. n. Prior to 2002, a USPA instructional rating for supervising student jumps.
- JUMPMASTER CERTIFICATION COURSE (JCC): A course registered with and authorized by USPA Headquarters to train, qualify and test applicants for the USPA Jumpmaster rating. May be conducted by an Instructor rating holder.
K
- KEY: A signal to move on to the next step in a skydive.
- KILL LINE: Line through bridle which collapses pilot chute after canopy opens to reduce drag.
- KING AIR: A turbine aircraft made by Beechcraft and common in medium sized drop zones.
L
- LANDING PATTERN: n. The deliberate flight path, usually rectangular, that a jumper uses in the final phase of descent under canopy.
- LAUNCH: Two or more jumpers exiting the aircraft together (stable).
- LICENSE: Certificate of proficiency recognizing that a skydiver has met a specified level of experience, skill, and knowledge. There are four classes of USPA licenses: A, B, C and D. USPA licenses are recognized internationally through the FAI.
- LINE DOCK: The docking of two canopies with the canopy above the head of the person receiving the dock; an advanced CRW technique useful for plane formations.
- LINE OF FLIGHT: An imaginary line corresponding to the jump plane's path over the ground, the line of flight is a useful reference line on larger formation skydives. Also, during the jump run the skydivers will be distributed along this line of flight.
- LINE TWIST: n. A condition of parachute opening where the canopy has attained full or nearly full inflation but one or more complete twists have developed in the lines and/or risers. Can be dangerous when associated with a spin.
- LINEOVER: n. A partial malfunction of a deployed parachute resulting in lines going over the top of the canopy. Also refers loosely to the partial inversion of a round canopy. (see also Partial Inversion)
- LOG BOOK: Like pilots or sailors, skydivers log their activity and achievements in order to document their experience.
- LORAN: A navigational system similar to GPS except based on ground transmitters, LORAN is relatively obsolete.
M
- MAE WEST: n. WWII term for partial inversion.
- MAIN PARACHUTE or MAIN: The primary canopy of a dual (two-canopy) assembly.
- MAINTENANCE: Inspection, overhaul, repair, preservation and replacement of parts.
- MAJOR ALTERATION: An alteration not listed in the manufacturer. s specifications: 1. that might appreciably affect weight, structural strength, performance, flight characteristics or other qualities affecting airworthiness; or 2. that cannot be done by elementary operations.
- MAJOR REPAIR: A repair that if improperly accomplished may affect weight, structural strength, performance, flight characteristics or other qualities which determine airworthiness.
- MALFUNCTION or MAL: The complete or partial failure of a parachute canopy to accomplish proper opening, descent or flight characteristics.
- MANIFEST: 1) The list of skydivers on the jump plane. 2) The act of going to the office where this list is maintained to put yourself on a plane. 3) The location where manifesting takes place.
- MASTER RIGGER: The higher of two certification levels for FAA riggers. May perform more complex repair tasks and approved alterations. (also see Senior Rigger)
- MICROLINE: A modern type of suspension line considerably smaller than dacron line.
- MILITARY SPECIFICATION: A procurement specification promulgated by a military agency and used for the procurement of military supplies and equipment.
- MINI-THREE RING: Refers to a scaled-down version of the original three-ring release system. (see also three-ring release).
- MINOR ALTERATION: An alteration other than a major alteration.
- MINOR REPAIR: A repair other than a major repair.
- MODIFICATION: 1. An alteration. 2. Often refers to the removal of an area of a round canopy to achieve steerability and forward glide.
- MSL: Mean sea level. Used by pilots when defining altitude, MSL refers to feet above sea level as opposed to above the ground. Pilots always use MSL when referring to altitude.
N
- NAS 804: National Aircraft Standard 804 defines the tests and minimum performance and safety standards which must be met for a parachute to receive approval under TSO C-23b. Adopted in 1949 and superseded in 1984 by AS 8015A.
- NASSER TOGGLES: Control loops on the front risers attached to one or more A or A-B lines to facilitate diving the canopy toward a canopy formation. Designed by Nasser Basir.
- NATIONAL AERONAUTIC ASSOCIATION (NAA): The National Aero Club of the USA which represents the FAI. USPA is a division of the NAA.
- NATIONAL COLLEGIATE PARACHUTING COMMITTEE (NCPC): Supports and encourages skydiving as a collegiate sport; conducts an annual national collegiate parachuting championships.
- NATIONAL DIRECTOR: Those Directors elected at large by the general membership.
- NIGHT JUMP: A skydive made from one hour after official sunset to one hour before official sunrise. The FAA considers any jump made after sunset and before sunrise a night jump.
- NOTAM: Notice to Airmen. An air traffic advisory or notice filed with an ATC facility by an airspace user.
- NOVICE: A skydiver who has been cleared to self-jumpmaster, but who has not yet obtained a USPA license.
O
- OBJECT: Any item other than a person that descends to the surface from an aircraft in flight when a parachute is used or is intended to be used during all or part of the descent. (FAR 105 definition).
- OPEN BODY OF WATER: A body of water in which a skydiver might drown upon landing.
- OPENING SHOCK or FORCE: The decelerating force exerted on the load as the parachute deploys and inflates. Caused by the resistance of the canopy and items associated with it. Also called opening shock.
- OPENING POINT: The ground point of reference over which the skydiver should open the parachute in order to most easily fly to the center of the target area.\
- ORGANIZER: Someone with leadership skills and skydiving expertise who plans formation skydives.
- OSCILLATION: 1. The swinging or pendulum motion of the suspended load under a canopy. 2. In CRW, the swaying or swinging of a CRW formation caused by poor docking, turbulent air or too much movement of the people in the formation.
- OTTER: The DeHavilland Twin Otter, a very popular turbine jump ship carrying up to 23 jumpers.
- OUT LANDING: Landing off target and/or off the drop zone.
- OUT OF DATE: See in date.
- OUTBOARD: Facing to the outside, such as a ripcord facing to the side of the jumper rather than toward the breast bone.
P
- PACK (or PARACHUTE PACK): An FAA term for the parachute assembly less the harness. It means the container, canopy, suspension lines, pilot chute, risers and connector links. The terms pack and container are not synonymous.
- PACKING DATA CARD: See data card.
- PARACHUTE ASSEMBLY: Consists of these seven component parts: harness, container, ripcord, risers, canopy, pilot chute and deployment device.
- PARACHUTE: A fabric device that slows the descent of a falling object; derived from the French words "para", to shield, and "chute," to fall. Thus, parachute literally means "to shield from a fall."
- PARACHUTE DROP: The descent of an object to the surface from an aircraft in flight when a parachute is used or intended to be used during all or part of that descent. (FAR 105 definition).
- PARACHUTE JUMP: A parachute operation that involves the descent of one or more persons to the surface from an aircraft in flight when an aircraft is used or intended to be used during all or part of that descent. (FAR 105 definition).
- PARACHUTE LANDING FALL (PLF): n. A method developed by the U.S. military to minimize the chance of injury from a hard landing under parachute. The jumper distributes the force of the landing in an orderly manner over the most robust areas of the body.
- PARACHUTE OPERATION: The performance of all activity for the purpose of, or in support of, a parachute jump or a parachute drop. This parachute operation can involve, but is not limited to, the following persons: parachutist, parachutist in command and passenger in tandem parachute operations, drop zone or owner or operator, jump master, certificated parachute rigger, or pilot. (FAR 105 definition).
- PARACHUTIST: A person engaging in intentional parachuting such as a skydiver, member of a military airborne unit or smoke jumper.
- PARACHUTIST IN COMMAND: Means the person responsible for the operation and safety of a tandem parachute operation. (FAA definition) Not necessarily a USPA instructional rating holder.
- PARAGLIDING: n. (also Parapente): An activity involving the use of a ram-air inflated wing, resembling a parachute, for gliding. Flights typically initiate by foot-launching from a hill or from a ground-based tow. Because paragliding jumping does not meet the FAA's definition of "the descent of an object to the surface from an aircraft in flight," it is not regulated by the FAA or addressed by USPA.
- PARASKI: Combination ski/accuracy event.
- PARTIAL INVERSION: A type of round canopy malfunction. It occurs when one or more sections of the canopy become inverted during inflation and form a small pocket which inflates, causing the canopy to be divided into two sections. The condition may or may not work out or may become a total inversion (where the canopy turns completely inside out). Also called a Mae West or lineover.
- PASSENGER PARACHUTIST: A person who boards an aircraft, acting as other than the parachutist in command of a tandem parachute operation, with the intent of exiting the aircraft while in flight using the forward harness of a dual harness tandem parachute system to descend to the surface. (FAR 105 definition)..
- PEAS: Pea gravel, used in the landing area as a target reference and because it is forgiving of hard landings.
- PERMEABILITY: The amount or volume of air which can pass through the fabric.
- PILOT: Person whom flys and is in charge of the plane.
- PILOT CHUTE: A small parachute used to aid or accelerate canopy deployment by acting as an anchor.
- PILOT CHUTE ASSIST: A connection of breakcord, velcro, etc., between the static line and the pilot chute which pulls the pilot chute out of the pack and then separates from it.
- PIN: 1) The skydiver who first gets to the base. Base/pin are the two people around which many formations are built. 2) The act of docking on the base. 3) The closing pin of the main or reserve container, which should both be checked prior to jumping.
- PIN CHECK: n. Pre-jump inspection of the main and reserve parachute pins.
- PIT: The pea gravel area.
- PLANE: A vertical CRW formation with the grip being feet of one jumper in the risers of another.
- PLA: The parachute landing area where it is intended skydivers/parachutist will land.
- PLANFORM: The shape or footprint of a wing surface.
- PLANING: In CRW, the transition from a stack to a plane, accomplished by the lower jumper adding brakes while the person planing pulls evenly with both hands on the lower jumper. s lines until his feet are at the risers. It is important for the person planing to keep his feet in the lines until reaching the risers to avoid deforming lower person. s canopy.
- PLF: Parachute landing fall. A technique used to minimize injury during rough landings, a PLF distributes the landing shock along feet, calves, thighs, hip and shoulder.
- POINT: 1) In FS or CF, each successfully completed formation scores one point. The formations themselves are often referred to in this way. 2) In CF, the last position in a diamond group.
- POISED EXIT: A departure from an aircraft wherein the jumper uses an external structure to brace himself and to assist in gaining a stable position immediately upon leaving the aircraft.
- POROSITY: The ratio of open area to closed area in a fabric. Graded as high, low or zero. Tightly woven material has a lower porosity than loosely woven material.
- PORTER: A single engined turbine aircraft carrying up to ten jumpers.
- POST DIVE: Review of a skydive after everyone has landed.
- PRO-DYTTER: A type of altitude warning device which gives additional freefall speed and distance information.
- PRO-PACK: One way of packing a square canopy.
- PRO RATING: A USPA rating indicating competence to perform difficult demonstration jumps.
- PRACTICE DEPLOYMENT: An in-air exercise used to learn how to locate an operate a parachute deployment handle prior to opening. It may consist of pulling or throwing a practice or dummy handle (instructor-assisted deployment or static-line jumps) or touching the actual deployment handle in freefall or tandem droguefall.
- PRACTICE RIPCORD PULL (PRCP): An exercise used to learn how to properly locate, reach and pull a ripcord handle. It may consist of pulling a practice or dummy handle or touching an actual or live handle. See DUMMY RIPCORD PULL.
- PRACTICE PILOT CHUTE PULL (PPCP): Term used in IAD training to simulate pulling the real pilot chute by pulling a fake or practice pilot chute on a training jump.
- PREMATURE OPENING: Opening of a parachute before the user is clear of the aircraft; any accidental opening of a parachute.
- PROP BLAST: 1. n. The airflow created by a propeller that is developing thrust. 2. n. relative wind on exit
- PUD: n. An aerodynamically low-profile, soft handle that is ergonomically designed to fit into a clenched fist. Used for various parachute operation handles.
- PULL: Deploy main parachute (also dump).
- PULL OUT: A hand deployment method of initiating parachute opening, where the springless pilot chute is packed into the main container. Pulling a handle first withdraws a container closing pin and then extracts the pilot chute.
- PULL UP CORD: A piece of cord or line used to pull the closing loop through the grommets of the container.
R
- RAM AIR: A modern "square" parachute, these inflate with air (rammed into the front) and take on a aerodynamic profile, much like an aircraft's wing, allowing them to be flown rather than just descending like an old style round parachute.
- RATING RENEWAL SEMINAR: A meeting of USPA Jumpmasters and Instructors to exchange, discuss and introduce new ideas to develop, improve or assure the quality of techniques of skydiving instruction.
- RECOMMENDATIONS: Principles, policies and concepts applicable to skydiving or a related subject which are derived from experience or theory, compiled by USPA and offered for guidance.
- REGIONALS: Regional championships.
- REGIONAL DIRECTOR: Those Directors of a specified geographical area, elected by and responsible for representing the interests of the skydivers in a Regional area.
- RELATIVE WIND: The apparent wind felt by a jumper in freefall, relative wind is the result of the skydiver's speed through the air.
- RELATIVE WORK (RW): Aerial maneuvers by two or more freefalling skydivers with each other, usually to form geometric formations (see Formation Skydiving).
- RESERVE PARACHUTE: The second or auxiliary parachute worn by a person making an intentional jump.
- RESERVE RIDE: To use the Reserve Parachute.
- RESERVE STATIC LINE (RSL): A line or lanyard attached to a main parachute riser and to a reserve ripcord handle, cable or housing to effect automatic activation of the reserve ripcord pin following a breakaway. Also called a Stevens system.
- REVERSE FLIGHT (FULL STALL): A non-flying canopy maneuver that collapses the canopy and may cause it to spin. Results from depressing the toggles until the trailing edge is lower than the leading edge. May result in an unrecoverable malfunction. (see also Stall and Dynamic Stall).
- RIB: A vertical and longitudinal fabric membrane that forms the airfoil shape and primary structure of a ram-air canopy.
- RIG: Skydiver slang for the entire parachute, including main and reserve canopies and the harness/container.
- RIGGER: Someone with a certificate from the FAA stating they have successfully met the requirements to be a parachute rigger.
- RIGGER'S CERTIFICATE: The certificate possessed by a rigger as proof of competence. Senior riggers may make minor repairs and pack reserve and main parachutes. Master riggers may make major repairs and alterations as well as packing parachutes.
- RIPCORD: The deployment system on all reserves and most student parachutes. The ripcord is a piece of cable with a handle at one end and a pin at the other. When pulled, the pin comes out of the closing loop holding the container shut, and the pilot chute is released.
- RISER(S): The webbing that connects the harness to the suspension lines. At the bottom of the risers will be a mechanism for attaching and releasing the risers and harness, usually in the form of a three ring release. On the rear risers are the brakes/steering lines. The suspension lines attach to the top of the risers with connector links, also known as rapid links.
- RISER DOCK: In CRW, a momentum dock that puts the risers into the hands of the receiver. A very advanced technique.
- RISER LOOPS; RISER BLOCKS: Gripping loops or devices on a riser that make it easier to grasp.
- ROUND: 1) A formation where each skydiver has grips on the arms of those next to him, also known as a star. 2) A round parachute, as opposed to a modern ram-air "square" parachute.
- ROUND PARACHUTE: A round parachute. These range from non-steerable to a bit steer able and the user is mainly at the mercy of the wind. Cannot really be flared and give fairly hard landings. Works by providing drag to slow the descent of the Skydiver.
- RSL: Reserve static line. This is a line from the main risers to the reserve cable. In the event the main is cut away, it may pull the reserve pin. Note: this system is only effective in malfunctions where the main is at least partially deployed.
- RUN-IN: Final line that the aircraft flies to reach the pre determined spot for jumpers to leave. Also called jump run.
- RUNNING: When a canopy is flying with the ambient wind it is said to be running. This produces the greatest possible ground speed.
- RW: Relative work, the term used to describe formation skydiving until a change in nomenclature made by the International Parachuting Commission in the early 90s.
S
- SAFETY & TRAINING ADVISOR (S&TA): A local person appointed by the Regional Director as his representative who is available to provide advice and administrative assistance as the USPA representative at an individual drop zone.
- SANCTIONED DROP ZONE: A drop zone which has been verified by a USPA Safety & Training Advisor or a USPA Regional Director as complying with the minimum drop zone requirements as stated in the USPA Basic Safety Requirements section of the USPA Skydiver's Information Manual.
- SCR: The oldest award for formation skydiving achievement, for those who have been in a star of at least eight people in which each person left the aircraft separately and flew to the formation.
- SEAL: Reserve parachutes have a small lead seal on a piece of red thread around the closing pin. This seal indicates the reserve has not been opened since it left the riggers hands.
- SELF-SUPERVISION: The point within a student’s training when he has been cleared by a USPA Instructor to jump without instructor supervision but has not yet completed all of the requirements for the USPA A license. (See Category E: Introduction of the Integrated Student Program.)
- SENIOR RIGGER: The initial certification level for FAA riggers that allows its holder to pack and maintain a parachute system and perform simple repairs. (see Master Rigger)
- SENTINEL: A type of AAD.
- SIM: Skydiver's Information Manual. Published by the USPA, the SIM is a comprehensive manual on USPA policies and training methods. It also includes FARs pertinent to skydiving.
- SINGLE-HARNESS, DUAL-PARACHUTE SYSTEM: The combination of a main parachute, approved reserve parachute, and approved single-person harness and dual-parachute container. This parachute system may have an operational automatic activation device installed. (FAR 105 definition).
- SINGLE OPERATION SYSTEM (SOS): The term refers to any system which combines a single-point riser release and a reserve ripcord so that pulling one handle will both release the risers and pull the reserve. Also called a combination system.
- SIT FLY: Freefalling in a sit position.
- SKY SHARK: An unwanted airplane in a drop zone area.
- SKYBOARD: (see Surfboard).
- SKYDIVE: 1. n. The descent of a person to the surface from an aircraft in flight when he or she uses or intends to use a parachute during all or part of that descent. 2. v. To jump form an aircraft with a parachute.
- SKYDIVER: A person who engages in skydiving.
- SKYDIVER'S INFORMATION MANUAL (SIM), USPA: The official bound collection of the USPA Basic Safety Requirements, USPA recommendations, relevant FAA references, and other USPA policies and programs that affect the majority of skydivers.
- SKYGOD: Although on the surface this term refers to a superior skydiver, in drop zone use skygod is a derogatory term for a skydiver whose ego has grown faster than his skydiving ability.
- SKYSURF: Skydiving on a surfboard.
- SKYSURFER: A skydiver who jumps with a surfboard (skyboard).
- SKYSURFING: 1. A freefall skydiving discipline using a specially rigged surfboard (skyboard). 2. The competition event by that name.
- S/L: Static Line, a deployment system for beginners (except AFF and tandem).
- SLIDER: A device which controls a canopy’s inflation by slowing down the deployment of ram air parachutes and then progressively sliding down the suspension lines during deployment. Found on most ram-air canopies.
- SLINKS: A type of Spectra fabric connector link developed by Performance Designs, Inc., for attaching the lines of the parachute to the risers.
- SLOT: A position in the skydive or on the plane. Uses: "dock in your slot", or "two slots left on the next Otter".
- SNIVEL: Abnormally slow canopy opening.
- SOLO STUDENT: A skydiving student who uses a single-harness, dual-parachute system.
- SOS: Single Operation System. This system simplifies emergency procedures by combining the functions of the cut away and reserve handles in a single handle.
- SPAN: 1) The dimension of a wing measured from tip to tip. 2) a bridge
- SPECTA: A material from which microline is made.
- SPEED: A competition where jumpers build a formation as quickly as possible.
- SPORT PARACHUTIST: One who engages in skydiving. A skydiver.
- SPOT: The EXIT POINT: The position of the aircraft when the jumpers exit. Spotting duties (selecting the spot) can be done by a skydiver or the pilot.
- SPOTTING: Selecting the course for the aircraft to fly, directing the pilot and selecting the correct ground reference point over which to leave the aircraft.
- SQUARE: A ram air parachute as opposed to a round parachute.
- STABLE FREEFALL POSITION: A position attained by a freefalling skydiver in which only controlled, planned movements are made; usually face to earth.
- STABILIZER: The vertical strips of cloth depending from the end cells of the canopy. Stabilizers improve the canopy's ability to fly straight ahead and enhance efficiency by reducing tip vortices.
- STABILITY: That property of a body which causes it, when its equilibrium is disturbed, to develop forces or movements tending to restore the original condition. In skydiving, having control of body position during freefall.
- STACK: A vertical CRW formation with the jumpers gripping the canopy or lines just below the canopy.
- STALL: When the angle of attack of a wing becomes too high to sustain lift, the wing is said to be stalled. When toggles are pulled down further than full brakes, causing the canopy to lose forward speed and collapse.
- STATIC LINE (S/L): A line, cable or webbing, one end of which is fastened to the pack, the other to some part of the aircraft; used to open a container or deploy a canopy as the load falls away from the aircraft.
- STATIC LINE JUMP: A parachute jump during which deployment of the parachute is initiated by a static line attached to the aircraft, used primarily in student training.
- STEERING LINES: The lines that run from the steering toggles on the rear risers to the trailing edge of the parachute.
- STEERING TOGGLES: Handles attached to the end of the steering lines to facilitate their use. Toggles and lines are configured so they can be stowed in a partially down position to enhance the opening of the parachute.
- STEP-THROUGH: (see Tread-through).
- STOW: To neatly arrange suspension lines on the deployment bag or steering toggles in their keepers.
- STREAMER: 1) When the main canopy has left the bag but not inflated at all. 2) Also sometimes a slang name for a WDI.
- STUDENT: A skydiver trainee who has not been cleared to self-jumpmaster.
- STYLE: A type of freefall competition where an individual skydiver attempts to execute a predetermined sequence of maneuvers in the shortest possible time.
- SUPERVISION: The general oversight of an activity taking place where the supervisor is readily available for counsel and direction and who is responsible that the activity is satisfactorily completed. (see Direct Supervision).
- SURFBOARD (SKYBOARD): n. A rigid panel, similar to a snowboard, attached to a jumper's feet.
- SUSPENSION LINES: Cords that connect the parachute to the harness. They are the means by which the wearer or weight is suspended from the inflated canopy. The lines from the risers to the canopy. They are normally in four groups, labeled from front to back as A, B, C and D. They can be further divided into right and left or front and back riser groups, and by type of material.
- SWOOP: 1) To dive down to a formation or individual in freefall. 2) To aggressively approach the landing area in order to produce a long, flat flare and an exciting landing.
- SWOOP POND; SWOOP DITCH: A water obstacle used as a high-performance landing area.
T
- TANDEM JUMP or TANDEM: A skydive during which two people use the same parachute system, each wearing a harness with one attached to the other and featuring a single piggyback container system with an extra-large main and reserve canopy.
- TANDEM PARACHUTE OPERATION: A parachute operation in which more than one person simultaneously uses the same tandem parachute system while descending to the surface from an aircraft in flight. (FAR 105 definition).
- TANDEM PARACHUTE SYSTEM: The combination of a main parachute, approved reserve parachute, and approved harness and dual parachute container, and a separate approved forward harness for a passenger parachutist. This parachute system must have an operational automatic activation device installed. (FAR 105 definition).
- TARGET: The landing area on a drop zone. For competition, a five centimeter disk.
- TECHNICAL STANDARD ORDER (TSO): Issued by the FAA, requires compliance with minimum performance standards and specifications for material and products. Parachutes are covered by TSO-C23.
- TERMINAL VELOCITY: The equilibrium velocity that a freefalling body can attain against the resistance of the air. The greatest speed at which a human body falls through the atmosphere. Resistance of the air overcoming the pull of gravity establishes the approximate figure of 150 to 176 feet per second or 102 to 120 mph for the stable, face-to-earth position.
- THREAD THROUGH (STEP-THROUGH): n. A leg strap configuration on a parachute harness that uses a single piece of adjustable hardware. The leg strap must be un-threaded to be disconnected, or the jumper simply steps into the connected leg straps when donning the rig. (see B-12s).
- THREE-RING RELEASE: A patented canopy release system based on three interlocking rings. In its common configuration, pulling one breakaway handle simultaneously releases both main risers. Also called a single point release. See CUTAWAY HANDLE.
- THROW OUT: A hand deployment method of initiating a parachute opening where the skydiver grasps a springless pilot chute and tosses it into the airstream. See HAND-DEPLOY PILOT CHUTE.
- TIME OUT: Audible altitude warning device
- TOGGLES: Handles on the steering lines.
- TOTAL: Malfunction where there is nothing out of the container.
- TRACKING or TRACK: A freefall action achieved by a skydiver (usually using a delta position) to attain maximum horizontal movement.
- TWO-FOR-ONES or TRIM TABS: A front riser pulley system for adjusting a canopys angle of attack or flight attitude.
- TSO-C23: The Technical Standard Order assigned to parachutes. See TECHNICAL STANDARD ORDER.
- TURBULENCE: Disturbed air that can affect canopy flight and integrity.
- TURF SURF: A long, flat skim across the grass and gentle landing that follows a properly timed and executed high performance landing (see hookturn) . When mistimed the result is a turf eat.
- TURN AROUND LOAD: When the aircraft does not shut down between loads, but lands and picks up skydivers for immediate departure.
- TWO-HANDLED SYSTEM: Refers to a parachute harness and container operation system that uses separate handles for the canopy release and for reserve activation.
U
- UNITED STATES PARACHUTE ASSOCIATION (USPA): A not-for-profit, voluntary membership association of skydivers whose purpose is promoting and representing skydiving. As a division of the NAA, it is the official representative of the FAI for skydiving in the U.S.
- UPPERS: The upper winds, or winds at exit altitude. The "uppers" are often much stronger and occasionally from a different direction than ground winds.
- UPWIND: The direction from which the wind is blowing.
- USPA BOARD OF DIRECTORS (BOD): Those representatives elected by the general members of USPA every two years as set forth in the USPA By-Laws; authorized by the By-Laws to have general charge and control of the affairs, funds and property of the organization and to carry out the objectives of the organization and its By-Laws; elects officers from among current Board members. The USPA Board of Directors consists of: 1. National Directorsthose Directors elected at large by the general membership; and 2. Regional Directorsthose Directors of a specified geographical area, elected by and responsible for representing the interests of the skydivers in a Regional area.
- USPA LICENSE: Formal recognition that a skydiver has met a specified level of experience, skill and knowledge. There are four classes of USPA licenses: A, B, C and D. USPA licenses are recognized internationally through the FAI and exceed the minimum requirements established for each level by the FAI.
W
- WARP: A CRW term that twists the canopy to decrease it flight properties.
- WAVE OFF: Prior to deployment a skydiver should make a clearly defined arm motion to indicate to others nearby that he is about to open his parachute. A good wave off is essential to the avoidance of deployment collisions.
- WAIVERS: Exceptions to the BSRs filed by those so indicated in USPA Section 2-2.
- WATER JUMP: A skydive which includes landing in an open body of water.
- WEIGHTS: Many lighter skydivers wear a weight vest to allow them to maintain a fast fall rate.
- WIND DRIFT INDICATOR (WDI): A device used to determine the wind drift which a descending parachute will experience, so constructed as to descend at a rate comparable to a skydiver of average weight descending under a fully deployed main canopy of average specifications. Usually a weighted strip of crepe paper 10 inches wide and 20 feet long.
- WIND LINE: An imaginary line from the desired landing area, extending directly along the direction the wind is blowing.
- WINDS ALOFT: See uppers.
- WING LOADING: The ratio of weight born by a wing to its surface area. In the US, divide your exit weight in pounds by the square footage of the canopy.
- WING SUIT: A gliding jumpsuit designed with fabric membranes between the legs of the jumper and from each arm to the torso.
- WUFFO: Skydiver slang for people who don't jump, from "Wuffo you jump out of them planes?"
Z
- ZERO-P (ZP): (Zero Porosity) Non-porous to air. (Not technically the correct term, but it's the one Skydivers use). Air does not go through it making ZP Canopies very efficient wings. Common slang for a type of fabric relatively impermeable to air. The less air that flows through the fabric wing of a ram air parachute, the more efficiently it flies.
- ZOO: A jump that didn’t go quite as planned!
- ZOO-LOAD: A group going to jump that probably won’t go quite as planned!