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Home > G-suit > G-suit Basics:
- What is a g-suit?
- How does a g-suit work?
- What does a g-suit look like?
- Why is a g-suit used?
- What are positive G's?
- Why would you need a g-suit?
- How is a g-suit put on?
- How is the size of a g-suit adjusted?
- How is a g-suit inflated?
- Where does the hose go when not in use?
- What are these zippers for?
- What are these pockets for?
- What are these Velcro strips and elastic straps for?
- What is this leather pocket used for?
G-suit Basics
What is a g-suit?
A standard g-suit is like a pair of chaps, with an air bladder that inflates over 5 areas of the body - at the abdomen, the front of each thigh, and the side of each calf - and cut-outs that allow for mobility at the knees and groin.
How does a g-suit work?
The air bladder inflates in the front of the body and puts pressure on the abdomen (abdominal aorta) and legs. It then pulls the material tight around the sides and back of the legs. This pressure around the muscles helps prevent blood from pooling in the feet and legs. It also helps to push blood back up to the heart and brain.
What does a g-suit look like?
See G-suit Pictures for photos and close-up details of a g-suit that is being worn while inflated.
Why is a g-suit used?
A g-suit is an anti-gravity garment worn by fighter pilots. When they are pulling positive G's, the suit inflates and prevents blood from pooling in their feet and legs which would cause them to lose consciousness. NASA astronauts also wear g-suits when they experience Orthostatic Intolerance (OI).
What are positive G's?
Gravitational (G) forces are experienced on a roller coaster ride. At the bottom of the hill, several positive Gs (+Gz) push one back in the seat. It feels like several times one's body weight. It is usually not enough positive G forces to cause fainting in a healthy person. At the top of the hill, negative G forces lift one out of the seat and a feeling of weightlessness is experienced.
Why would you need a g-suit?
I have learned that Chronic Fatigue Syndrome (CFS) is not about being tired and not having energy, but is related to Orthostatic Intolerance (OI) where blood pools in the feet and legs when sitting or standing. (OI is also a part of many other illnesses besides CFS.) Figuring the g-suit would work the same way it does for fighter pilots and NASA astronauts, I have successfully used the g-suit to relieve some CFS/OI symptoms.
How is a g-suit put on?
I start by putting the g-suit around the waist and closing the clasps and zipper at the right hip. (The hose is at the left, front side.) Then I pull each leg around and close the clasp (at the thigh) and snap (at the ankle) and zip the zipper all the way down the inside of the leg. (The tab at the thigh is helpful to hold onto.) (See also Fitting the G-suit - Getting In and Out.)
How is the size of a g-suit adjusted?
There are six shoelace type lacings to adjust the size to make it bigger or smaller. (See also Fitting the G-suit - Making Smaller.) They are covered by flaps with velcro and are located at each calf, behind each thigh, and two are at the lower back. (Once the lacings are adjusted so the g-suit fits correctly and comfortably, they do not need to be adjusted every time the g-suit is put on.)
How is a g-suit inflated?
Even without an F-16 fighter jet handy, the g-suit can still be easily inflated. I just release the valve at the end of the hose by pushing on the plunger and blow into it. There is no resistance and the g-suit inflates easily. Even fully inflated manually, the g-suit is not hard to walk around in. I have played tennis, bicycled, rollerbladed, ice skated, gone horseback riding, and driven in it!
Where does the hose go when not in use?
There is velcro on the hose that can be attached to the velcro on the left thigh of the g-suit or the hose can be tucked into the parachute knife pocket that is also on the left thigh. This is helpful so the valve does not swing and bang against furniture. When putting the hose in the pocket, be careful not to let the g-suit deflate because of pressure against the plunger of the valve.
What are these zippers for?
On the outside of each leg, there are comfort zippers. They are opened by fighter pilots when they are not flying to make the g-suit looser.
What are these pockets for?
There are large pockets on each lower leg. They are used by fighter pilots for holding things like their gloves. I do not use them.
What are these Velcro strips and elastic straps for?
On the front of the g-suit, there are Velcro strips and sometimes elastic straps on the thighs. They are used by fighter pilots to hold navigational maps and information while flying.
What is this leather pocket used for?
There is a pocket called a shroud knife pocket or pouch on the left thigh with leather outside and a snap. It holds a knife for fighter pilots that is used in various emergencies. (A shroud is one of the ropes on a parachute.)