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 - Aircraft.
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 Accelerated Free Fall -
An AFF student receives training on freefall
jumps of 40 seconds or longer, accompanied by
a qualified jumpmaster, as opposed to Static
Line training which does not involve long freefall
in the initial training phase.
AGL. Above Ground Level - Altitudes
are in reference either to Ground Level of Sea
Level (see MSL). Skydivers always use AGL when
referring to altitude.
Airspeed - The speed of a flying
object through the air, commonly used in reference
to aircraft or canopies.
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.
Apparent wind - The wind perceived
by an observer. See relative wind.
ASP - Skydive Arizona's version
of AFF, the Accelerated Skydiving Program includes
two tandem jumps and an enhanced version of
the AFF syllabus.
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.
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.
Base - The core around which
a formation Skydive is built. Can be a single
person or a group of people, depending on the
number of Skydivers involved.
BASE jump - A jump made from
a fixed object rather than an aircraft. BASE
is an acronym for building, antennae, spans
(bridges) and earth (cliff).
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.
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.
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.
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 off - To cease formation
skydiving by tracking away from the formation
prior to deployment.
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.
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 fabric and lines used to land safely after
a freefall. Usually used in conjunction with
a type reference (round, square, zero-p, main
or reserve).
Cascade - The point where
two lines join together so they run smoothly
into one. Cascading the suspension lines results
in reduced bulk and drag.
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.
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.
Chute assis - French for sit
flying, or freefalling with one's seat presented
to the relative wind.
Closing loop - The small loop
that holds the flaps of the container closed
once the pin has been guided through the loop.
Coach - A Skydiver with some
formal training in the art of instructing freefall
technique.
Container - The element of
the parachute that houses the canopies. Technically,
the Harness/Container but usually just referred
to as the container.
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
in a creeper.
Creeper - A board equipped
with wheels on which a Skydiver lays to simulate
freefall maneuvers.
Cross ports - Holes in the
ribs of a cell that allow air to flow from one
cell to another.
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 away - To release the
main parachute, cutting away is a standard emergency
procedure prior to deploying the reserve. More
properly known as a breakaway, the technique
did involve using a simple release system activated
by pulling a handle.
CRW - Canopy Relative Work,
now officially known as Canopy Formations. CRW
involves flying open canopies in close formation,
where the pilots actually take grips on each
other's parachutes.
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.
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.
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.
Dead spider - Slang for de-arch.
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.
Dirt dive - To rehearse a
Skydive on the ground.
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.
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.
Drop zone - Common slang for a skydiving
center, also DZ.
Dytter - A brand of audible
altimeter.
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 cell furthers
out on a canopy.
Exit weight - The total weight
of the jumper and all equipment and clothing.
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.
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 - The act of pulling
down the brakes of the canopy in order to slow
it down, resulting in an increased angle of
attack and reduced descent rate.
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.
Freestyle - A type of skydiving
characterized by acrobatic individual flying,
reminiscent of gymnastics.
FS - Formation Skydiving, formerly
known as relative work. In FS, Skydivers attempt
to go through a predetermined sequence of freefall
formations.
Formation - 1) A freefall skydiving
formation of more than one jumper. 2) A flight
of more than one jump plane.
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.
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.
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.
Hand deploy - To activate the
parachute by manually deploying the pilot chute
as opposed to pulling a ripcord.
Harness/container - The webbing
and fabric holding the main and reserve canopies
to the Skydiver.
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 small knife
carried in the jumpsuit or on the parachute
harness, the hook knife is designed to cut lines
or webbing. A small razor blade is recessed
in a hook shaped handle to prevent unintentional
cuts.
Hook turn - A turn of 90 degrees
or more executed close to the ground. Because
of the high risk associated with this maneuver,
hook turns have an unfavorable connotation.
Hot fuel - When the airplane
does not shut down during fueling. Do not board
the aircraft while fueling is in progress.
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 - Someone who has
held a USPA jumpmaster rating for at least one
year and passed an Instructor Certification
Course.
IPC - The International Parachuting
Commission oversees sport parachuting. It is
a committee of the FAI.
Jump
run - The
flight path taken by the jump plane to put the
Skydivers in position over the airport.
Jumpsuit - A cover all type
garment designed for specific skydiving applications
such as FS, freestyle or accuracy.
Jumpmaster - Someone who has
successfully attended a USPA Jumpmaster Certification
Course. A jumpmaster has all of the privileges
of an Instructor except that they cannot supervise
a first jump course, sign off licenses, or manage
a student program without an instructor's supervision.
Key - A signal to move on to
the next step in a Skydive.
King Air - A turbine aircraft
made by Beechcraft and common in medium sized
drop zones.
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.
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.
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.
Main - The primary parachute.
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.
Microline - A modern type
of suspension line considerably smaller than
dacron line.
N
Organizer - Someone with leadership
skills and skydiving expertise who plans formation
Skydives.
Otter - The DeHavilland Twin Otter,
a very popular turbine jump ship carrying up
to 23 jumpers.
Out landing - Landing off
target.
Out of date -See in date.
Packing data card - See data card.
Peas - Pea gravel, used in
the landing area as a target reference and because
it is forgiving of hard landings.
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.
Pit - The pea gravel area.
Pilot chute - A small, round
parachute that acts as a drogue to extract the
main parachute from the container and deploy
it.
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.
Porter - A single engined turbine
aircraft carrying up to ten jumpers.
Post dive - Review of a Skydive
after everyone has landed.
PRO rating - A USPA rating
indicating competence to perform difficult demonstration
jumps.
Pull out - A type of hand
deploy pilot chute where the pilot chute is
packed inside the container and pulled out using
a handle with a lanyard to the pilot chute.
Pull up cord - A piece of
cord or line used to pull the closing loop through
the grommets of the container.
Pud - Slang for the handle
on a pull out pilot chute system.
Q
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.
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.
Relative wind - The apparent
wind felt by a jumper in freefall, relative
wind is the result of the Skydiver's speed through
the air.
Reserve - The auxiliary parachute
carried on every intentional parachute jump.
Rip cord - 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.
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.
Risers - 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.
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.
Running - When a canopy is flying
with the ambient wind it is said to be running.
This produces the greatest possible ground speed.
S&TA. Safety and Training Advisor
- The S&TA is a volunteer representative
of USPA who attempts to disseminate information
about safety and act as a liaison between the
DZ and USPA. Most S&TAs hold instructor
ratings.
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.
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.
SOS - Single Operation System.
This system simplifies emergency procedures
by combining the functions of the cut away and
reserve handles in a single handle.
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.
Sentinel - A type of AAD.
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.
Slider - A rectangular piece
of nylon fabric with a grommet at each corner
through which the canopy's suspension lines
are routed. Packed at the top of the lines,
the slider controls the opening of the canopy
by preventing the parachute from expanding too
rapidly.
Slot - A position in the Skydive
or on the plane. Uses: "dock in your slot",
or "two slots left on the next Otter".
Spectra - A material from
which microline is made.
Spot - The position of the
aircraft when the jumpers exit. Spotting duties
(selecting the spot) can be done by a Skydiver
or the pilot.
Square - A ram air parachute
as opposed to a round parachute.
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.
Stall - When the angle of attack
of a wing becomes too high to sustain lift,
the wing is said to be stalled.
Static line - In static line deployments
the parachute deployment system is attached
to the airplane, with a cord ten to fifteen
feet long, resulting in deployment immediately
after exit.
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.
Stow - To neatly arrange suspension
lines on the deployment bag or steering toggles
in their keepers.
Style - A type of freefall
competition where an individual Skydiver attempts
to execute a predetermined sequence of maneuvers
in the shortest possible time.
Suspension lines - 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.
Tandem - Parachute jumps in
which two Skydivers, usually an instructor and
student, share one parachute system. The student
is in a separate harness that attaches to the
front of the instructor's harness.
Terminal velocity - The speed
at which drag matches the pull of gravity, resulting
in a constant fall rate. Typical terminal velocity
for formation skydiving is in the 120 to 135
mile per hour range, but speeds as high as 300
miles per hour have been reached.
Three ring - A parachute release
mechanism that utilizes three rings of separate
size in a mechanical advantage system. Invented
by Bill Booth in the late 70s, the three ring
release is almost universally considered the
best cut away system available.
Throw out - A deployment method
in which the pilot chute is stowed in a pouch
on the belly, leg of bottom of container.
Toggles - Handles on the steering
lines.
Track - To assume a body position that
creates a high forward speed. Used to approach
or depart from other Skydivers in freefall.
TSO. Technical Standard Order -
A technical standard that all American parachutes
must meet before they can be marketed. Unless
specifically exempted by the FAA, a parachute
must have a TSO placard to be legal.
Turn around load - When the aircraft
does not shut down between loads, but lands
and picks up Skydivers for immediate departure.
-
Uppers - The upper winds, or
winds at exit altitude. The "uppers"
are often much stronger and occasionally from
a different direction than ground winds.
USPA - The United States Parachute
Association is a non profit Skydiver's organization.
USPA offers guidance and assistance to Skydivers
in training, government relations, competition,
and many other fields. Most drop zones require
USPA membership of individual Skydivers because
such membership includes third party liability
insurance.
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.
WDI - Wind drift indicator.
A paper streamer thrown from the jump plane
to estimate winds under canopy and determine
the spot.
Weights - Many lighter Skydivers
wear a weight vest to allow them to maintain
a fast fall rate.
Wuffo - Skydiver slang for people
who don't jump, from "Wuffo you jump out
of them planes?"
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.
X.Y
Zero-p - 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.
