There you are, at about 4,000 feet AGL, falling at a good 120 miles per hour at the planet we call home, and it's time to deploy your parachute. You arch for stability, put your legs out slightly, reach with your left hand as you move your right down to the hackey on your pilot chute, and throw it. Nice job. Count to five while looking over your shoulder at the nicely-inflating parach...Wait. That doesn't look right at all.
How to recognize a parachute malfunction
The first step in saving your life on the event of a parachute malfunction is recognizing that there's a problem. A malfunction as far as parachutes are concerned means anything that would keep you from landing safely. Unfortunately, parachutes are complex and the number of things that could cause you to be unable to land are numerous. Luckily, an easy-to-follow four-step program has been devised for you to check your canopy for damage and other problems. Once you've become familiar with it, it should only take a few seconds to check everything and be confident that your canopy is landable. There's a mnemonic and everything! It's called...
The 4 S's
If your canopy is Square, Stable, Steerable, and the Slider is down, you've got a good canopy. By "good canopy," I mean "safe to land with."
- Square (or Shape)
Square is a bit of a misnomer, since the parachute isn't exactly a square; modern ram-air parachutes are actually rectangular. Square in this context means: does the canopy have a clearly defined rectangular shape with filled-out corners? If not, you don't want it.
Is the canopy flying stable? A stable canopy flies straight with no input (steering), it doesn't wobble or hesitate. Originally, I worried about recognizing an unstable canopy, but think of it this way: the canopy is a wing. It generates lift and acts in every way like an airplane wing, except that it's unpowered and you're tied to it. Wings (and aircraft) should fly straight and not rock, flutter, or wobble.
- Slider down
There's a rectangular piece of fabric (or plastic, or whatever) on your parachute called the slider. Its purpose in life is to keep the parachute from opening too quickly. It's important because the opening shock causes quite a bit of deceleration, and your poor body could be damaged by the forces involved in such things. Anyway, the slider plays its role by sliding down the lines connecting the parachute to the harness. Aptly named, no? However, if the slider doesn't slide as it's supposed to, your parachute isn't open. The slider must be at least halfway down the lines for this test to pass.
If you've passed the S checks so far, unstow your brakes; it's time to make sure you can actually steer the parachute. Turn right and left and make sure the parachute's doing what it's supposed to. Attempt to flare the parachute and make sure it does. If it doesn't do this with the steering lines, you may still be able to steer and flare with the risers; but the whole point of having this check is to make sure you can do all of these things while you've still got the time to cutaway if something's wrong.
Once you're used to how the checks go, you'll be able to pass/fail these within a few seconds of opening. If any of these four checks fail, your canopy is not landable. You will probably want to get rid of it. Initiate emergency procedures, but remember not to cutaway under 1,000 feet.