When you've never made a sport skydive, the art of jumping out the airplane door at the right time to land in the middle of a ten-foot circle might sound like some sorta voodoo. Far from it, in fact. The art of the skydiving landing has been honed over the course of many, many years (since the 1950s!) and inspired a windfall of exciting changes in parachuting technology. If you're more interested in skydiving landing techniques than technology, we're happy to throw a little light on how skydivers know how to land accurately from so far up. (Spoiler: It is not magic, though we might swan around a little bit when it goes especially well.)
When you're in the plane, look around the door for the "traffic light." You'll see a three-light system somewhere over there, with a red, yellow and green. The light is clearly red (and the door, usually, closed) when the pilot does not want us to leave the plane. Yellow indicates that the door should go up and we should be ready to exit.
Here's where it gets a little complicated. A green light doesn't necessarily mean that the pilot is telling us to leave the plane; it just means that the pilot has completed all of her responsibilities: the aircraft is flying at the right speed and trim to allow for our safe exit, and air traffic control has been told that skydivers are about to leave the aircraft. The green light means "it's okay by me" from the pilot; to see if it's okay by us, we need to do a little more thinking.
There's a GPS system on nearly every skydiving aircraft in the air. The introduction of that tech was, of course, a game-changer. It changed the game, of course, in the direction of precision. Most skydiving pilots fly their skydiving "jump runs" into the wind, on a heading determined by GPS. From there, however, we skydivers have to make sure we're in the right place to get out.
On the ground, we will have informed ourselves of the speed of the winds aloft, as well as the forecasted wind speeds and directions. In the sky, we do a visual check of the location of the landing area to suss out if it's too far away. If we haven't gotten into the right airspace yet, we wait; if we've passed it, we ask for a "go round" to avoid having to land "out."
From there, the process is pretty straightforward, but there are certainly steps that we take. We look straight down from the door, checking for any other air traffic. We make a mental note of our direction of flight and of our exit point. Then we look at the landing area and double-check that we're within a landable distance of it. Generally, for us "fun jumpers," physically pointing at the landing area to check that we're pointing pretty much straight down is a good rule of thumb.
Once we've completed the freefall portion of the jump and we're under our parachutes, the skydiving landing techniques we use start to revolve around our canopy piloting skills. We use the radial optic flow pattern to zone in on the exact spot we've chosen to land in while keeping our heads on a swivel for other jumpers and non-jumper air traffic. (Some pilots do some pretty fancy tricks in this portion of the skydive.) At any rate, we use the controls of our ram-air canopies to guide us down, then complete a "flare" to slow and soften the landing. We usually land within a scant few meters of our target--or directly on top of it. Some pilots can actually land, quite literally, on a dime.
That said: do you know what the best advice is that we've ever heard on how to land a parachute safely? Make sure your brain is turned on and connected. Skydiving landing accuracy techniques are the logical procedures produced by safety-focused, well-trained heads that are mindful of others and cool under pressure. That's just the kind of heads that fill the helmets at Jumptown, as a matter of fact!