Collision Avoidance!

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Article by Lesley Gale and Maxine Tate

Almost a canopy collision but some prompt avoidance action saved the day …

Collision Avoidance by Jos Berentsen

“During the second day of the Flanders Boogie at Moorsele, Belgium, after a successful FS 12-way jump we separated at 4,500 ft. My teammate and I both had an off-heading opening and turned directly into each other. When I saw him I was really scared that we were gonna have a canopy collision. As soon as my canopy was open I pulled my right rear riser to avoid the collision. We both felt lucky to walk away unharmed.”

Jos Berentsen

Thankfully Jos’s evasive manoeuvre avoided a collision but there are lessons we can all take from the video. It’s better to avoid the potential collision scenario than have to avoid the canopy.

What can we learn?

1. Separation altitude

A 4,500 feet breakoff is on the low side for a 12-way boogie jump with a fairly random group of people. 5,000 feet would have been more prudent.

Five jumpers open within about 45 degrees of each other

2. Separation direction

The time to create separation is in the track. There are a number of canopies all opening very closely. We see at least 5 people all tracking off within about 90 degrees of each other. And then 4 to the right, so that’s nine on a 12-way tracking in one half of the sky. So, the biggest learning point here is to spread out in choosing your direction when turning and tracking away. In theory a 5-6 second track for a 12 way should create good separation if everyone picks a different direction. This is roughly defined by taking a line from the centrepoint of the formation to your centrepoint and following that direction – NOT an automatic 180° turn from your position in the formation. It’s always worth thinking and talking about track-off direction from the various planned formations.

Good flat track – dearched, arms creating lift, long legs, angled to the horizon

3. Learn to flat track

A flat turn away from the formation and a de-arch in the track will achieve good horizontal separation. The jumpers in the video are losing altitude in their turns and still arching in their tracks, causing downward ‘diving’ movement and covering less horizontal distance. People who often jump in a small group like a 4-way can get lazy about tracking; instead, always focus on good separation. People have been killed in collisions on 4-way jumps too.

See Flat Tracking article by Christy West, for great advice on tracking skills.

4. On-heading openings

There are at least 3 off-heading openings on a 12-way, that’s 25% of the load, not an acceptable average. Pay attention to a symmetrical body position on deployment and controlling your opening with your whole body. Learn to pack symmetrically for an on-heading opening. Don’t pack faster than you are comfortable with to keep up with the speed of the boogie group, get a packer. Be aware if you change to a higher performance parachute you may need to adjust your packing technique to get consistent, on-heading openings. If you are having repeated off-heading openings, seek qualified advice on your packing technique and get a rigger to check out your gear; you may need to have your main canopy relined, or replace your pilot chute.

5. Be aware

Look at others during your track and open at a safe altitude but away from traffic. Be aware of other jumpers opening near your airspace. The rule of sod (and Dan BC) says that if they have an off-heading opening, it will be towards you! 😉 So be ready to take fast, evasive action if needed.

If you normally jump in small groups at your home dropzone then be aware of the added complications of larger formations – exit, build, break-off, tracking, opening, flying and landing are all more hazardous with more people involved.

6. Collision avoidance

The goal is to keep flying away from the formation for another few seconds to increase the separation created during the track. If you have had an off-heading opening, then you must look up and scan your airspace. A small heading change such as 45 degrees can be easily corrected back on heading again, but if you have a more pronounced heading change such as a 180 you have to assess and fly into clear airspace.

In any possible collision scenario, regardless of who had the off-heading opening, if someone is approaching from your top right then you turn left and down; if someone is coming from lower left, you go up and right. If someone is coming head on then default to right. You must fly away from the other jumper, wherever that may be. Use risers because it’s much faster than releasing the toggles.

7. Under canopy

When you are under an open canopy, always look around in 3 dimensions before collapsing your slider, or taking off your booties, or making any turns.

8. Assess your awareness level

The video is a reminder that incidents can happen quickly on any skydive. That’s why it’s important to make your own decisions when you are fit to jump. Be okay with standing down because you are tired, hungover, drained from a long day in the heat or just not feeling very ‘with it’.

Stay safe out there!

Article by Lesley Gale, Skydive Mag and Maxine Tate, Flight-1

Meet: Lesley Gale

Lesley has been in love with skydiving for 35 years. She is a multiple world and national record holder and a coach on 20 successful record events worldwide. She has over 100 competition medals spanning more than 25 years and has been on the British 8-way National team at World events. She started Skydive Mag to spread knowledge, information and passion about our amazing sport.
Lesley is delighted to be sponsored by Performance Designs, Sun Path, Cypres, Cookie, Symbiosis suits and Larsen & Brusgaard

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