Tip Tuesday: Preparing for BASE
Beau Riebe on getting ready for BASE by working on piloting skills...
The second in a 4-part series by Matt Gerdes and Taya Weiss. First article, on the First Flight Course, is here, this article covers WS exits. Firstly, exit order, and some of the counterintuitive things that should be considered when mixing groups. Secondly, exit technique, something that lots of experienced pilots are still getting wrong, and a source of much stress for DZs in terms of tail strikes…
While some DZs may have their own special rules for their own special reasons, the consensus among WS pros is that there are almost no exceptions to this rule: Wingsuits Exit Last. Vertical, belly, tandems, etc… that all makes sense, right? But what about high-pullers?
Since this seems to be the only common source of confusion about exit order and wingsuits, let's break it down:
First, we plan the exit order for the successful execution of each group's plan. It's the same for wingsuits and high-pulls. Wingsuits exit last, because of their low vertical speed and their extensive horizontal reach. It is very easy for a wingsuit to exit and remain under and near to the aircraft for several seconds.
If a high-puller is pulling “right out the door”, and therefore still wants to get out last, they may not understand that there is still a high likelihood that their opening will continue right into the wingsuit's path of flight. And if the high-puller exits last and takes even a slightly longer delay than they announced, they could end up cannonballing right through the beginning of the wingsuit flight path, and then also become a dangerous obstacle under parachute for wingsuits on the load, even if there are multiple passes.
If a high-puller is concerned with wingsuits flubbing their exit and turning back down jump run, then like every other potential conflict on a load, the best thing that everyone can do is stick to their plan. Like vertical flyers pledge to execute a vertical skydive, high-pullers must actually execute their high pull at the stated altitude, and wingsuits must fly their intended plan inside the established lanes. With adequate exit separation, it is exceedingly difficult for a wingsuit to exit, complete a 180, and collide with a normally loaded parachute. The most likely scenario is that the wingsuits exit down jump run, begin their flight in the direction of jump run, and their vertical speed (sink rate) will put them well below the high-puller before their horizontal planes can cross.
One reasonable exception would be experienced CRW jumpers who are exiting with a large enough offset (exit separation) to create distance between themselves and wingsuits. However, in short, the lowest chances of collision between wingsuits and high-pulls are when wingsuits exit last, with normal exit separation.
Whether or not an extra pass becomes necessary or recommended depends on the airspace that is available at your DZ, and the number of wingsuit and tracking groups on the plane. If your DZ has two established lanes of flight, and hopefully two established parachute opening “zones” (one opening zone for each lane and group), then there should only be two groups per pass. There are very few DZs on Earth where more than three groups can exit and fly safely back to the DZ.
Organize the wingsuit groups on each pass in terms of vertical speed - conventional wisdom states smallest suits first, biggest suits last, but never assume that big suits will be flying slowly because they could be on a high speed angle-style dive, in which case they may need to exit before small suits.
Let's look at a possible example, which is surprisingly common at dropzones with a lot of experienced wingsuiters:
An Otter load is manifested with eleven wingsuit pilots in four groups. Also on the plane are a four-way belly group, three freeflyers, an AFF level 6, and a tandem. Wow, full load, sure wish those wingsuits would scrunch up, we're missing a seat, someone sit up front, and hey Todd Davis would you please exhale and think skinny thoughts? Thanks. Regardless of how many passes there will be, and it looks like at least two, the wingsuits will be exiting last so all of them will get on first.
Non-wingsuit skydivers exit as per normal, with tandem last.
The four wingsuit groups are split up like this, and loaded in reverse order:
WS Group 1: A two-way group consisting of a beginner wingsuiter and their coach, both in small suits. They will fly within the DZ's established “Wingsuit Lane 1”, and exit first of the wingsuits (after the tandem, and after checking their spot and aircraft settings) on the first pass. The duo will open their parachutes in the intended opening zone for Lane 1.
WS Group 2: A five-way group of small suits planning a formation. They will stay within the DZ’s established “Wingsuit Lane 2” and give the student + instructor two-way a wide berth.
WS Group 3: A two-way group flying medium and large suits at a normal speed. They will begin their jump inside Lane 1 and execute break-off with enough altitude to open their parachutes in the intended zone.
WS Group 4: A two-way flying large suits, flying a normal vertical speed and intending to stay within “Wingsuit Lane 2”, and opening in the intended zone for lane 2 flyers.
What if Scotty Bob or Carlos Pedro Briceno is on the load, and they want to do a steep angle jump? A pre-boarding discussion should reveal the fact that this might not be the best load to plan that style of jump, because it would be difficult to add it in without the potential for conflict. Even if they exit first on the second pass, there is still the potential that their high vertical speed could put them near to the first pass groups. If they exit first on the first pass, then there is the chance of them interacting with the tandem, unless they plan for that and begin their jump with a transit glide, increasing their separation but also consuming altitude, which most jumpers do not want to do and will tend to cut short. Don’t be so attached to your wishes that you endanger other people on the load, and try to communicate with manifest and the other jumpers at the DZ about your plans before gearing up.
Remember: Don’t be afraid to move groups into different planes. Prevent potential conflict by discussing flight plans before manifesting.
The specific plans and conditions of every group and jump must be weighed in order to determine the uses and limitations of available airspace. Some loads may only have one wingsuit group on them if the group’s composition, plans, and/or size require flexible use of the airspace (for example, a highly experienced dynamic group with many turns and transitions). Other restrictions on number of groups per load might be winds aloft, high pulling freefallers on the same or proximate loads, multiple jump runs, etc. Bottom line: There might not be room on this load for you or your group - find out, and manifest appropriately.
NOTE: The plane, and the pilot
If you jump at a large DZ, or small DZ, it is worth talking to whoever is responsible for coordinating jump run for wingsuits. There are a variety of factors at play, and it’s not as simple as reducing the indicated airspeed of the aircraft. Power settings, deck angle, and rate of descent all come into play. It’s worth learning about. For more info, see: ___vimeo.com/flysquirrel/tails_
Wingsuit exits are firstly about the tail of the aircraft. Stability, navigation, and a successful approach to the group are the subsequent priorities. Before exiting, you should be thinking about (in order) the tail, your stability relative to the group, and finally your own personal stability. Please note that your personal stability is third priority here - it’s more important to not cause a plane crash or a mid-air collision than it is to have a comfortable and stable exit.
it’s more important to not cause a plane crash or a mid-air collision than it is to have a comfortable and stable exit
Most discussion regarding proper exit posture centers around surface area of your arm and leg wings, which is important. But as suits have evolved, planforms have extended the arm wing into areas that cannot be fully “closed” simply by restraining your arms. What this means is that our good habits need to evolve “beyond closure”, and include angle of attack (AoA) with regard to the relative wind and prop blast.
When exiting the plane, be conscious of the fact that the higher your AoA, the more you will be pushed up and back, in the direction of the tail. Particularly in intermediate and advanced wingsuits, closure + low AoA is important. Think of how a penguin slides into water, and imagine yourself sliding head first into the relative wind instead of belly-flopping against it.
An exit with the proper AoA and minimum surface area presented (arm and leg wings truly and properly closed) to the relative wind is unlikely to result in a tail strike or an unstable exit - and as a bonus, you’ll be flying sooner and therefore joining the formation sooner.
NB – We do NOT jump from the plane! We dive out, and down!
Opening arm wings too soon
If you don’t know where your hands are, your arm wings could be open. Every instructor has a different technique, but most of them involve an exercise to increase awareness of your arm position. If you can feel your hands grabbing another part of your suit in a wings-closed posture, then you are less likely to make an error in proprioception, or limb-awareness, which could result in an open wing.
Losing awareness of aircraft tail
If you can’t see the tail of the aircraft, you might not be past it: Advice varies, but most advice includes training for an awareness of the aircraft. If you have had a close call, or want an exercise to help prevent tail strikes, think about watching the tail clear you - maintain good posture and AoA until you watch the tail pass you, when you know it’s safe to open up.
Don’t! A good wingsuit exit never ever involves jumping up. There is never any reason to jump up out of the door. Dive out and down, if anything. If you are having a hard time with this, imagine what it feels like to put your hand on a low fence and swing your legs over it. From a low position, put your right hand (if it’s a left side door) on the floor in the door, and swing your legs out as you exit with the top of your head (and spine axis) pointed into the relative wind. This should keep your torso more level to the relative wind, and prevent any upward exit tendencies.
Losing awareness of aircraft settings
Know what proper wingsuit exit conditions feel like, sound like, and look like. Check for them before exiting. This varies with aircraft type, but in general: Turbine power should be reduced / cut, flaps should be at least partially down (varies with aircraft), airspeed should be reduced, deck angle should be level, pilot should be aware of wingsuits ready-to-exit.
Before exiting, run a quick checklist:
Write it on your hand, if you need to!
This article is one of a 4-part series by Matt Gerdes and Taya Weiss on Wingsuit Progression. Here are links to the other articles:
Part 1 – First Flight Course - previous article - here
Part 2 – WS Exits from the Plane - this article - here
Part 3 – A Wingsuit Skydive from Start to Finish - next article - here
Part 4 – Making it Back (alive and well) - here