Altimeter: Looks like a clock face with a single hand. It shows your height above the ground, in thousand foot increments. Audible altimeters beep when you fall through a preset altitude. These are only a backup for a visual altimeter since if they don't work they don't tell you that they haven't worked, or if you don't hear them they won't remind you. Audible alti's are often used by freefall camera people and freestylists since they cannot look at their visual alti's as often as they'd like.

Automatic Activation Device: A mechanical or electronic device which automatically opens the main or reserve parachute at a set altitude as a back up for the user. Usually used for student and experienced jumper's Reserves.

AFF: Accelerated Freefall Course. The most advanced method of learning to skydive. A 7 Level ability based learning progression. It is the course that is accelerated, not the speed of the Freefall. You have a Terminal Velocity of about 120 mph in freefall which ever type of course you choose!

AFF CC: (Accelerated Freefall Jumpmaster Certification Course). This is the Certification Course that must be successfully completed in order for a skydiver to be an USPA Accelerated Freefall Jumpmaster. Most Jumpmasters will tell you it is the most difficult rating to achieve in skydiving.

BIC: (Basic instructors course) Attended in an effort to gain a sufficient level of proficiency with reference to teaching.

Boogie: A usually large skydiver gathering or celebration. Many times these are made to commemorate a significant anniversary or event. Most "Boogies" include evening parties, specialty aircraft, and/or discount skydiving prices to post AFF graduate or licensed skydivers.

Canopy: Skydiver talk for a 'Parachute'. See Main Parachute, Reserve Parachute, Square Parachute, Round Parachute, and Elliptical Parachute.

Container: The part of a Rig which contains the Main and Reserve Parachutes.

Canopy Relative Work (CRW): Pronounced CReW. Skydiver talk for Canopy Stacking where Skydivers under canopy link up to create formations.

Cells: The chambers in a ram-air parachute, made up of two halves. They are delimited by two load bearing ribs and are split in two by the non-load-bearing rib in between. Most Skydiving Canopies have either 9 or 7 Cells, but they may have as few as 5 or many more than 9 and a Cell may be split into more than 2 parts. A 9 Cell Canopy is generally a more efficient wing than a 7 Cell because it has more ribs and can be a better airfoil, however because they have more ribs and therefore more fabric they do not pack as small.

Dirt Dive: Practicing a dive on the ground before the jump so that all involved understand exactly what will occur in the sky - since there is not much time up their and you can't discuss it with a 120 mph wind going past your head.

Elliptical Parachute: Like a Square except elliptical rather than rectangular. These Canopies are far more radical than Square parachutes doing 360 degree turns in 1-2 seconds, with the Skydiver and Parachute parallel to the ground. There are variations between Square and Elliptical, some called Semi-Elliptical.

FAA: Federal Aviation Administration: Aka. the sky police.

FAI: Federation Aeronautique Internationale: The international body which administers sport aviation throughout the world.

Fall Rate: The rate at which you fall, another name for terminal velocity except that it refers the rate relative to other jumpers, rather than an absolute velocity. Fall rate is adjusted by adjusting body position. Different shape and weight jumpers in exactly the same body position will fall at different rates. Fall rate must be adjusted to be the same as everyone else so that the jumper can do RW.

Formation: When referring to RW a formation is a group of skydivers forming particular pattern by taking grips on each others arms and legs. The formations that will be done on a jump are determined and practiced (Dirt Dived) before the jump. When referring to CRW it is a formation of Canopies flying together in a predetermined configuration.

Grips: Sausage shaped things attached to the arms and legs of a jumpsuit for skydivers to hold on to in formations.

ICC: (Instructor certification course) The course one must attend and successfully pass in order to obtain an instructor rating.

Harness: The part of a Rig which consists of webbing and metal hardware which you wear and which the Container is attached to.

Main Parachute: The parachute you use first. If it doesn't work you use your Reserve. This happens very rarely and there are Skydivers with thousands of jumps and no Reserve rides. The Main parachute is usually much higher performance than the Reserve. There are many types and brands available, in custom colors for no extra cost if you want, and they come in all sizes from 69 sqft 9+ Cell parachutes, for very small, light and/or highly experienced Skydivers, to 280-300 sqft 7 or 9 Cells that students usually use, to 520 sqft 9+ Cells for large Tandem parachutes. These are all Square parachutes. Round parachutes are only used as mains for special applications - water jumps and Pilots Rigs for example.

Mal: Skydiver talk for Malfunction.

Malfunction: When the Main Parachute doesn't work properly. There are different degrees of malfunctions, the bad ones of which cause you to use your Reserve.

Parachutist: A person who uses a parachute. A Parachutist is not necessarily a Skydiver. A Skydiver is only a Parachutist because they have to be. Note for non-jumpers: do not call a Skydiver a Parachutist and don't ask them about 'their Parachuting'.

Pilot: A person who likes planes but usually does not jump out of them.

Relative Work (RW): Skydiver talk for Formation Skydiving where Skydivers in Freefall link up to create formations. This can be done in any numbers from 2-person (called a 2 Way Skydive) and up. Competition RW is mainly done in 4 person teams (4 Way Teams) and in 8 Ways & 16 Ways.

Reserve Parachute: The parachute you use if your Main Mals. Reserve parachutes must be tested to very strict standards & must be inspected and repacked by a specially licensed packer at regular intervals, (every six months in Australia), whether they have been used or not.

Reserve Ride: To use the Reserve Parachute.

Rig: What you would think of as 'The Parachute' in the phrase 'To Wear a Parachute'. Consists of a Harness, Container, Main Parachute, Reserve Parachute and the means of deploying each parachute.

Round Parachute: A round parachute. (We do not use these at Atlanta Skydiving Center). 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.

SkyGod: We still do not truly know how to define this term. Should you know its definition please let us know.

Square Parachute: An airfoil shaped ram-air parachute which is actually rectangular with aspect ratio's from less that 2 up to more than 3.5. The parachute is termed a 'semi rigid wing'. It is held in a wing shape by the air rushing in the front, keeping it pressurized. Squares work not by providing drag to slow the descent but by providing lift as they fly at about a 3:1 glide angle. They therefore must fly quite fast! and speeds up to 40-50mph in a straight line depending on the Canopy and the weight of the Skydiver are possible. They can be flown into the ground at in excess of 80 mph if one wants to. The most common configurations are 7 and 9 Cells and they can be made of porous material or non-porous Zero Porosity material.

Static Line Training: An outdated method of training skydivers. The type of training in which a Static Line - a piece of webbing connected from the airplane to the students Rig opens the parachute. Like in the old war movies where the soldiers are hooked up and then jump out, and their parachute opens immediately. (The static line is like in the old war movies, the rest of the course and the gear isn't anything like it!).

Tandem Skydiving: Atlanta Skydiving Centers recommended First Jump! The passenger and Instructor are harnessed together and use a the same main parachute, the student may participate as much or as little as he or she wishes.

Terminal Velocity: The speed at which a Skydiver falls when the friction of the air on their body is equal to and counter acts the force of gravity so that they no longer accelerate. It is about 120 mph in a flat stable position, lying on the air, face down. The Skydiver can fall faster or slower, up to a point, by changing their body position.

Track: To track is to assume a body position which gives a very high horizontal speed.

USPA: United States Parachute Association

Whuffo: Person observing skydiving activities from the ground sometimes with a dazed look on their face asking "Whuffo they do that?"

Zero Porosity (ZP/Zero-P): Means 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.

Certifications Defined

AFF JumpMaster: an individual who has obtained certification from the USPA that allows him or her to "JumpMaster" or coach AFF students. The minimum requirements to be eligible for this rating is any jumpmaster candidate must have 6 hours of logged freefall and must have successfully completed the AFF CC.

Camera Flyer: (Videographers) at Atlanta Skydiving Center must demonstrate a proficiency in human body flight and camera / video work, and must posses a superior personality. Only the best skydive video personnel in the country are selected to work at ASC.

Demo Jumper: An individual who has attained the level of experience and accuracy through canopy (parachute) manipulation necessary to land consistently in a confined area. These jumpers are certified capable of performing Demonstration Jumps into commercial venues.

Instructor: An individual who has obtained certification from the USPA that allows him or her to provide ground instruction or training to AFF skydiving students. An USPA instructors rating must be obtained prior to teaching a first jump or parachuting course. Minimum requirements that must be met in order to achieve this rating are the applicant must have successfully completed the BIC, must hold a valid USPA jumpmaster rating for a least one year, and complete an ICC.

Packer: One who has demonstrated an high level of proficiency packing MAIN parachutes.

Rigger: A person who has been properly trained to pack both main and Reserve parachutes. There are two levels of demonstrated proficiency, the Senior rigger and the Master rigger.

Tandem Master: An individual who has obtained certification from the USPA and a Tandem rig manufacturer permits him / her to make tandem skydives with (attached to) another skydiver or first time tandem jumper. Minimum requirements that must be met in order to achieve this rating are a minimum of 500 skydives, 3 years in the sport of skydiving, and have attended a tandem certification course.