Wires and water and trees, oh my . . .
You do have some control over the direction of flight - when jumping static line, US special forces jump a round chute that has steering toggles and holes cut in the back to give it some forward momentum (about 9.5 knots worth) and steerability. Even conventional forces like the 82nd Airborne, that jump the venerable T-10 round parachute with no steering toggles, can influence their direction a little bit by "slipping:" pulling on the riser (the nylon strap that holds the parachute to the parachute harness) in the direction they want to go. But you don't have a lot of control over where you end up. If the people planning the jump miscalculate the release point, or the winds at altitude, you may find yourself heading for an uncomfortable landing.
There are three major hazards you can find yourself heading for - water, trees and wires. (Sometimes a jump is deliberately planned for trees or water - that's a different situation calling for special equipment and planning.) I've never accidentally hit water, and never gone through wires, but I do have my share of tree landings - plus one near miss with a three story building.
The first time I hit the woods was many years ago, making a night combat equipment jump (a jump with a rucksack and weapon) from a Chinook helicopter. It's hard to hit the woods from a helicopter, but my entire chalk managed it that night (a chalk is all the parachutists put out in a single pass over the drop zone - if you're jumping from a high performance aircraft like the C-130, the same group is called a stick - I should know why, but I don't. Maybe the Air Force could afford sticks to line up behind, and the Army had to make do with chalk marks on the tarmac.)
Like I said, it's hard not to hit the DZ from a chopper, so it took a lot of work and cooperation from the jumpmaster and the pilots to get us into the woods. Fortunately, this was the first time the aircrew had dropped parachutist since it got certified to do so, and the jumpmaster was fresh from jumpmaster school and his requisite one safety before being allowed to jumpmaster on his own. It was just our team jumping into an exercise, and we wanted to put the entire team out, so we grabbed two jumpmasters from another team to run things (In a helicopter jump, the jumpmaster doesn't jump - instead of wearing a parachute, he's strapped into a harness - known affectionately as a "monkey harness" to keep from falling out the back.) One of the jumpmasters we's planned for, the more experienced one, got sick at the last minute, so we didn't have a lot of depth. Our company sergeant major, who was an excellent jumpmaster and was running the drop zone from the ground was having his own set of problems communicating with the aircraft, so there was every opportunity for things to go wrong.
It started with the blackout lights inside the Chinook - the Chinook was equipped with a row of red lights that wouldn't ruin your night vision, but the one right before the back had a cracked cover with a good bit of white light escaping - it was the last thing you'd see before stepping off the ramp.
The way we were jumping required the jumpmaster to spot a set of lights set up in an L shape - called a NATO L. The idea was that their was a reception party (a la the French Resistance, but in this case our sergeant major) on the ground. As soon as they saw the aircraft was coming in on the right heading, they would light the lights, the jumpmaster would see them, and we'd jump.
Under the jumpmasters direction, we went through the ritual of standing up, hooking up and checking equipment, and the crew chief opened the rear door and lowered the ramp. The red light beside the ramp came on, and our jumpmaster crawled out onto the ramp to spot for the panels.
We made three passes over the drop zone without the green light coming on. There's a special kind of agony that starts to build up when you stand up in a parachute harness and combat equipment for any length of time. The harness is pulled tight to minimize the snap from the opening shock of the parachute, and that, combined with the weight of the parachute, weapon and equipment, starts digging in and cutting of circulation. There's not a lot you can do to alleviate the pain - you don't have the option of sitting back down, and between having the keep the static line from getting looped around anything and having to keep the reserve ripcord grip from getting hung on anything, there's even a limited amount of squirming around that's possible. The last thing you want is to have to make multiple passes (called racetracks) over the DZ while people try to figure out whether to let you jump or not.
Finally, on the fourth pass, the jumpmaster stood up and gave us the command "Stand By!" Great, he had seen the lights, and we were getting off the bird. We shuffled closer to each other, and closer to the exit ramp. He knelt and peered over the edge of the ramp again, and stood back up. The jump light snapped from red to green. "GO!" The first man walked towards the ramp. I was the number two man, right behind him. As we headed for the ramp, it felt like the helicopter was changing direction, but it had to be an illusion - we wouldn't change direction once the pass had begun. I had carefully kept one eye closed because of the cracked light cover, but opened it walking down the ramp - and dammit, there went my night vision. I stepped off the ramp and started counting to make sure my parachute deployed in a reasonable length of time "One thousand! Two thousand! Three - ooof." It was a great exit - no twists and only a minimal opening shock. I reached up, grabbed the steering toggles, and started looking around to figure out where I was. I should have been able to look down and line up on the lights (they should have been set up in an L-shape and easy to spot) and figure out where the team was going to link up once we were all on the ground. I was a bit hampered by the afterimages of the Chinook light still floating in front of my eyes, but I didn't see any lights. I pulled one of the steering toggles and turned in a circle to take a look around - way, way off to my right, I saw a suspiciously L shaped glow. OK, if the DZ was over there - where was I? I looked down again and noticed my night vision had come back a bit. Below in the gloom, the ground had a suspiciously rounded and leafy appearance. Damn it. Looking down, I saw the road that ran off of the north of the drop zone - and the wind was blowing a bit in that direction. If I "ran" with the wind, I might be able to make the road instead of hitting the trees. Of course, if I didn't make the road, I was going to have a fair amount of speed built up. Oh well. At about 100' off of the ground, it became obvious that I wasn't going quite make the road. I turned to face into the wind to slow down a bit and saw the woods drifting up under me. Great.
I narrowly missed going straight into a big tree, and instead started pinballing down through its outer branches. I had expected that it would be like falling out of a tree and plunging through the branches to the ground, but it was a much more slow motion kind of crash than that: since my parachute was still inflated above me, I got to deal with one branch at a time instead of falling through them all at once - so it was WHAP - pause - THWACK - pause - WHAP - pause, until my parachute finally caught on the top branches of the tree and deflated. I hung there, thirty or forty feet off of the ground, for maybe 5 or 10 seconds, and had just started considering how I was going to get down when a CRACK! from above me jarred me and dropped me a few feet. I had just enough time to look up and consider that maybe the ride wasn't over yet when, with another CRACK!, I dropped through the branches, breaking them as I went - this time, it was like falling out of a tree. Fortunately, the parachute caught again with my feet a few feet off the ground. I popped my rucksack loose and undid my chest and leg straps, wriggling out of the harness. I gave the parachute a few tentative tugs and decided I wasn't getting it out of the tree by myself - at least without a chainsaw or a bucket truck - so I broke a chemlight and tied it to the harness so I could find it later. I picked up my rucksack and weapon and started towards the road - I had only missed it by about 20'. I had planned to head down the road back to the DZ and find out what was going on, but once I got onto the road, my attention was drawn to the sound of struggling and cursing coming from the woods on the other side. I plunged into the woods towards the commotion.
A few feet into the woods, I found the team commander trying to get down. One of the things they teach you about tree landings is not to lower your equipment - under normal circumstances, you drop your rucksack and weapon carrier a few hundred feet off the ground - they're attached to an 18' long coiled nylon line, called a lowering line. The lowering line uncoils and your rucksack dangles underneath you for the rest of the ride. If you think you're going to hit the trees, you leave the ruck where it is for additional protection. If you've already lowered to ruck, you jettison it before you hit the trees, for reasons that will become obvious.
So there he was, struggling to get to the quick release on his lowering line, which, because he was folded up like a card table, was hung under his reserve. His parachute was hung in one tree, and his rucksack was hung in the other one. His rucksack was higher than his parachute, so he was doubled over and mostly upside down, trying to get his hand under his weapons carrier and reserve to get rid of the rucksack. He told me later he thought he was going to make the road and he didn't want to smash up his rucksack, so he rode it in.
Since he was the boss, I didn't laugh as hard as I might have - well, alright, I did. He snapped at me, "Hey, give me a hand here - if you can push up on me, I can probably get to the quick release."
Well, if our beloved leader had a fault, it was that he always wanted a picture whenever he did cool guy stuff - if we were fast-roping, or doing a live fire, or he was jumpmastering, he was constantly pestering people to get a picture of him - and he always carried a camera for the purpose. "Hey" I had to ask, "are you sure you don't want me to get a picture before you get down?" "No, dammit," he replied, then he started laughing, "besides, my camera is in my rucksack." After a few minutes, we got him down. I narrowly missed getting beaned by his rucksack when it let loose. We walked in, picking up a few stragglers on the road as we headed in. One of them was new to the team, and was bitching like mad: "I've got over seventy jumps with the 82nd, and never hit the trees once." he complained, "My first jump on a team . . ." "Yeah, well," one of the other guys interjected, "Welcome to Special Forces."
When we got back to the DZ, we found out what probably happened. The chopper pilot was flying with NVGs (night vision devices) and the light they were using to guide him in was a really big 5 D-Cell flashlight with an infrared filter on it. The pilot had a lot of trouble seeing it using the night vision goggles, so finally he agreed to try to spot it without the NVGs. The sergeant major took off the infrared cover off the flashlight and told the pilot, "You should see a white light. Do you have the white light?" The pilot said he did, and began another pass. He was off a little bit to the north, but still over the DZ, so the ground party lit the DZ's NATO L and cleared him to drop, figuring he would correct over the lights.
The new jumpmaster had trouble spotting the lights, and mistook the flanker light for the release point - so he was already way too far north. As soon as the pass started, the helicopter pilot - still following the white light that he thought was the ground party - turned north to follow the white headlight coming from the road at the far end of the DZ. The sergeant major was screaming "Abort, Abort!" over the radio, but it was too late. Some guys got banged up on the way down, but we only had one real injury - one of our guys had a compound fracture of his femur - bone sticking out of his leg. In one of those moves that happened in SF from time to time, and made me wonder what the hell I thought I was doing, hanging out among the Army's real men, he managed to rig up a splint to keep the bone from moving around, and made it about 100' out to the road so somebody could pick him up - and he brought his weapon out with him. When the medic on the drop zone got to him, he immediately asked if he wanted something for the pain. I'd have been screaming for morphine at that point, but this guy looks at him and says, "Well, yeah, it does hurt a bit. Do you have any Tylenol with you?"
All in all, a painful night, although we did get to go back and get some sleep instead of continuing the exercise. We spent the next day with tree spikes, trucks and chainsaws getting our parachutes mostly out of the trees, although in a couple of cases all that came back was the harness - short of cutting the tree down, the parachute wasn't coming out.
The experience did give us a team motto, though: "Never trust a jumpmaster in a monkey harness."