Review: Indoor Wingsuit Tunnel
What's it like, flying in the WS tunnel?
Flight-1 share an alternative method of unravelling line twists. It's important to have a fast, efficient method to resolve line twists - remember this issue doesn't only occur with a main deployment. So just in case your reserve opens with twists, know how to get rid of them as quickly as possible.
Check how quick and simple the process is in this video:
Most skydivers will have experienced or are going to experience line twists after deployment. There are a number of factors that could cause them; here are a few suggestions from my colleague Pete Allum:
‘Let’s look at the various ways that your parachute can get itself into this condition;
For complete clarity, we want to start this section with a clear statement that always applies:
IMPORTANT: ALTITUDE IS KING. If you reach your decision altitude and you still don’t know if you have a good canopy that you can control and steer, it’s time to get rid of it. Nothing supersedes this in any circumstance. The purpose of this article is to give you an alternative way of resolving line twists only, you should still respect your own safety standards.
If you deploy, look up, and see that you have line twists to deal with, here’s some suggestions on how to proceed.
If your system (you and your canopy) is turning during this process here are a few tips to help stop the turn;
a. When you first push the risers together you may be able to spot any offset in the risers, creating asymmetrical inputs. It might be possible to bring the risers back into a symmetrical alignment by just pulling on the one furthest away.
b. It is also possible to stop a turn once the twists are in the risers by reaching up above the twists and steering out of the turn using the opposite rear riser to the direction of the turn – if you are turning to the right, grab the left rear riser above the twists and pull. NOTE: your canopy is steerable even when you have twists in the risers.
What is happening during this process and why is this method so fast and effective?
In order to unravel a twist we need rotation. Pulling on risers with twists in the lines does not create any rotation. At worst, if there is any existing offset in the risers then you are potentially pulling asymmetrically on the canopy and may worsen or induce a turn. Pushing the risers together at least takes the tension off the twists to minimize any such input.
Compare your system to being on a swing. You are a suspended heavy weight sitting on a wooden seat (harness) attached by chains (risers) to an A frame (canopy). Remember what is was like to twist the chains up by rotating under that swing… then lifting your legs up? As the chains are set apart from each other on the A frame there is enough torque (rotational force) for your body to rotate freely until all the twists in the chain unravel. That is the goal of moving the twists down from the lines into the risers – there will be enough torque for you to start the rotation of your body to unravel the twists from the risers. Very little torque exists when the twists are all the way up in the lines, which is why it can be time consuming to try to kick out from twists in the lines.
Understanding the rate at which you lose altitude with your system is a key factor to understanding whether you have enough altitude to try to resolve a nuisance factor such as line twists. For example if you know it takes your system 5 complete rotations from an aggressive toggle turn to lose 500 ft, then you have a good guesstimate of the amount of altitude you may lose with a tension knot, a toggle fire or indeed spinning from line twists.
Wearing a digital altimeter on the inside of your wrist will allow you to try to deal with nuisance factors AND see your altitude throughout the process.
One last time: Altitude is king and respect your own safety standards. And if both those factors allow, do what you can to resolve line twists with an effective, well thought-out plan of action. Good luck!
Note: These videos are hop and pops with deployment altitudes above 5,000 feet, giving the pilots more altitude than most standard freefall jumps to fix problems before reaching their decision altitude. From a 3,000 feet deployment there would be far less altitude to work in - have a decision altitude, know how much altitude it takes for your system to fully deploy and be aware of the size of your own expected window of opportunity.
Related article: Loss of Altitude