Tuesday, April 24, 2007

Scary Lesson III: The Compression Knot-head

I’d always hoped my first article here would have been about some epic day of flying, but things don’t always go as you’d like them to. Believe me, I would really have rather just forgotten about my Easter Sunday flight and pushed forward, but Alex and Ray prodded me a bit, and of course they’re right . . . if others might benefit from my near disaster then that’s a good thing. I know I appreciated Christine's and Alex’s earlier articles, so . . . here goes.

It was a typical day at Kahana. I hiked up with Scot, One-Eye Jim, and Deutsch Marc (Nickname credit: Scot), followed shortly by Alex and Ray. I had a solid flight. It was one of those where you kind of feel like all the pieces are finally coming together. I was really happy with the launch, flight, and landing. After landing the rain clouds moved in, so we took lunch at Uncle Bobo’s to wait it out.

Afterward Alex rallied the troops for another flight. I had never done two flights in a day and was feeling pretty good about things. I felt another flight like the first would really be confidence boost. So I eagerly hit the trail again. I set up on high launch with Scot set up just below me. Alex launched lower and was scratching around in light conditions, eventually top landing at low launch. The wind conditions had definitely dropped off since our earlier flights. I was eager and feeling confident though. I thought I had a decent chance of getting up from high launch.

Since I was ready and chomping at the bit Scott offered to let me go first. I popped the wing up partially and then aborted. The right side rolled over on the left. I climbed up and spread it out again. Ray had arrived by this time. I pulled up again and as I turned I heard Ray yell. But it was too late . . . I was on my way. Ray immediately came on the radio and was telling me “Go right, go right”, “Right? . . . the lift is left”. I felt the wing start to turn left. Ray was saying “Just fly the wing”. Something is wrong here. I looked up right. Nothing wrong there. I looked up left. Ah . . . there’s the problem.

I didn’t know exactly what the problem was, but the wing didn’t look right . . . and . . . well . . . I was heading for the beach. I weight shifted right and the wing steered right. As I aimed for the beach, I thought to myself, “Well I’m on my way there I should at least somewhat attempt to try and fix whatever was wrong.” I once saw Jimmy clear some branches from his wing over the beach at Crazy’s by pumping the brake several times. So I tried that. I pumped a few times. About this time I noticed that I probably wasn’t going to make the beach. But that’s okay, I’ve seen people go down in the trees before, that’s not so bad . . . there are worse things between launch and the beach, powerlines, highway, rocks, water . . . yeah, trees are okay.

I pumped again. The wing started turning left slow but strong. It turned 180 degrees, I weight shifted hard right. Ray called on the radio “Hands up!!! No brakes!!!” I put my hands up. It was too late. As I heard him say “Your going to stall” I went into a negative spin, as I was going around and around I remember thinking “Well buddy, you’re definitely going in the trees now . . . but that’s alright . . . the trees are alright”. Then I went into a full stall. As I dropped horizontally I only had time for one more thought, “Oh boy . . . this is going to hurt” Crack!!! I was still totally surprised with the violence in which I hit the tree with the back of my head . . . it broke the branch and broke my fall to the ground . . . and then it was over.

I was okay and on the radio before I could even tell if I was really completely okay. With the exception of my neck everything seemed fine, and even the neck, well . . . thankfully it wasn’t broken . . . I could turn it left and right. It was just very sore, especially looking down. Alex was at low launch and his radio wasn’t working. He had only witnessed the last dramatic part so he came bombing through the bushes to help within less than a minute of my plunge into the trees. He helped me get my wing out and back up to low launch and we even discussed a sledder to the beach, but it was killing my neck to just trying shut off my “friggin beeping friggin vario”. I still wasn’t sure if I might be needing a doctor or not and I could just see me trying to explain to him why after falling out of the sky I decided to fly again. Sometimes when things go wrong the keep going wrong, so there would be other days to “get back on the horse”.

Obviously there were a number of mistakes I made. Things I would have done differently?

Number 1: Avoid the compression knot. I was too eager setting up and didn’t check the lines again after it rolled over. I also focused too much on bringing the wing up stable and controlled and didn’t notice the knot. No compression knot. No problem.

Number 2: I shouldn’t have used the brake. I should have just weight shifted to the beach. I may have actually made it. My glide judgement isn’t perfect. Perhaps another right turn to a top landing might have been and option, but I’ve been advised the beach is the better choice.

Number 3: I should have been checked out by a doctor. Like Russell mentioned to me, sometimes you have swelling or internal bleeding that doesn’t show up right away. Better safe than sorry.

So I had two weeks of rehab and high winds to dwell on it all. Finally it was time to get back on the horse (no, not heroin). First flight was a quick turn and back to the beach. I gave up way too easy, maybe I was still a little spooked. Second flight, scratched, almost got up, but bombed out. Finally after the third hike I got up and thus avoiding bombing out from all three launches all in the same day. The next day followed with another solid flight.

Thanks very much to Alex and Ray for their help on the hill and Scot and Jim for their advice back on the beach. Any other comments and criticisms are welcome. I can take. If it’s going to help make me a better pilot, bring it on. I was lucky and I know it. Giddyup!!!


Brazilian Ray said...

good one, thanks for sharing this story!
I should have said to not even try to fix the problem, because it looked bad... I am glad you're ok!

sandy said...

Great article, Steve. Thanks for bringing it up. I've never suffered such a knot myself yet (so far as I know) knock on wood, but it's good to keep it on the forefront of our minds.

Some helpful points copied from our chatter:

scubadoRob: I once heard the only dumb question is the one never asked. I just read this article, and like the other ones I really appreciate the learning lessons from them. what is a compression knot?

25 Apr 07, 10:32
Alex: Rob, a compression knot is where lines are looped around themselves or each other - they are tightened by the pilots weight in flight, but usually come out easily when unloaded. Hence the compression.

Alex: Like an evil slipknot - typically the more you try to fix them in flight the tighter they get. And often you can't find them after you land because they just come out after you unload the wing.

25 Apr 07, 10:36
suicide: the the line becomes a knot. This changes the shape of the wing in proportion to the size of the knot. This decreases the flying efficency of the wing. Sometimes it can REALLY cause problems.

25 Apr 07, 10:34
suicide: Scuba . . . sometimes, while slack, the lines of a parglider get wrapped around one another. If the line is suddenly tightened (as with a launch, or a by trying two tug free of a snag)

Alex: Peter, I like your point about how it happens while the lines are slack

I would like to add that our weedy launches aid and abet the compression process, not only bunching lines together, but helping to create loops as well as hiding the knots from our eyes. When I'm on launch with others, I always try to assist in inspecting others' lines for potential knots and weedy snags. I especially do this for visitors who may not be used to such messy launches.

I would encourage other pilots to assist our friends in scanning their lines for such problems. Especially since you may actually have a better visual vantage point.

Christine said...

Scary story, Steve. Wow, I am glad you got away with a sore neck and a bad scare. Just wondering about the stall. Did you use both brakes or did you stall one side of the wing while pumping. It would be great if anyone who watched you explains what they saw from their perspective.
Thanks for sharing.

Brazilian Ray said...

Christine, I saw it all..... the knots (I am sure it was two) were so bad on the left side of the wing it was almost stalling the glider. Once Steve stopped focusing in just "fly the glider" to a safe landing at the beach, and tryed to fix the problem (pumping the brake) the glider started to turn (hard) to the left (loosing speed); to fix his tragectory, he applied right brake, slowing even more the glider and causing it to spin (the left side stalled; negative spin). A full stall has never happened.

compression knots are hard to fix during flight because of the load on the lines. A cravat may be possible to fix by pumping, but a compression knot I'd recommend to just fly to safety ;)

Anonymous said...

Everyone needs to be diligent about checking each others lines. Every time I'm on launch I scan your wings for problems...

You typically cannot fix a Compression knot in the air, and pulling in an Ear or ears can cause a more serious Cravat, thus resulting in more turning and more drag on the bad side. The 'Fix' for a cravat is to full stall the wing.

If you don't have enough altitude, you must steer the wing in the most efficient way possible. Most likely hard weight shift to the opposite side, and head for your best and easiest landing option. This may be the trees, water, or the hill? Your glide will surely be effected as well, so to make the beach (LZ) could also be a challenge.

If you have to make an emergency landing ALWAYS put your knees and feet together, tuck in your chin, and prepare for the impact. Don't forget to flare and if given the choice turn the glider into the wind to soften the impact. If you are landing in the trees cover your face and neck to protect yourself from puncture.

You also may have to throw your reserve if your in a bad situation. Don't wait for the problem to get really bad, when in doubt THROW...

The other most important thing is to have only ONE person yelling what to do, especially the most experienced. Too much yelling will cause confusion of the pilot and most likely make the situation worse.

After the pilot goes down, anyone attempting rescue MUST have a radio and or working cell phone. It never is good if you don't have commo. In the event the one best rescue person doesn't have a radio, loan them one or go with them...

Also, 911 is definitely a good option even if it means it might cause a commotion that we don't want at a particular site. The pilot's life may depend on it. A sore neck could be much more serious, let a professional decide if he or she needs medical attention.

Fly safe.

My two cents worth...


Christine said...

One addition to Reaper regarding medical help:
Don't necessarily trust the judgment of a pilot who just went down (and is possibly in shock) in regards of his/her evaluation of the extend of the injury. In Valle De Bravo we had one girl throw her reserve and braking her ankle badly on one leg, and a burst 8in (?) long deep wound on the other radioing in she was ok and we did not call an ambulance - until we saw her, when we got her out of the woods...

paliglydr said...

Excellent account, Steve. Thanks for taking the time to write it up. I've had a compression knot at Kahana too, and ended up flying to the beach. I really felt exasperated when I landed and couldn't find the blinking knot! Oh well... nature of the beast. Glad you took no serious injury. Hope to see you in the air again soon.