It has two simple jobs – and if either fails the results can be catastrophic…
I recently had the opportunity to speak with a newly licensed skydiver that had experienced an unintended AAD activation that led to a 2 out scenario rather low to the ground. The incident ended safely, with the jumper walking away from it uninjured.
As we spoke about what happened, I started to wonder how many other new jumpers could benefit from this conversation and decided to share the story (with the jumper’s permission) in an effort to raise awareness of the many roles that AADs play in our sport.
A relatively new skydiver operating a relatively large main parachute experienced an AAD fire while descending from 1,200ft into the pattern by making a deep spiraling toggle turn to enter their pattern altitude. The AAD was an M2 set in student mode, and it correctly activated at the appropriate altitude as the jumpers descent speed exceeded the operating parameters of the unit at the activation altitude, and it released the reserve pilot chute into the air after activation, resulting in a two-out scenario.
My AAD/coffee pot analogy
“Your AAD is like a coffee pot”. That was my first statement. “Coffee pots, like AADs have 2 jobs to do. We are all aware of the primary job of our coffee pot, to make coffee…for your AAD, it’s to activate (starting your reserve deployment sequence) if and when needed. But there is a second job for the coffee pot and the AAD, one that we don’t always think about…For your coffee pot, it’s not to burn the house down when it’s not making coffee…And for your AAD? It’s second job is not to activate when it’s not needed.” Both jobs are equally important, because if either job fails, the results can be catastrophic.
Now let’s open the case of your AAD (theoretically speaking) and look inside to see what we find. What do you see? It’s essentially just a calculator. A really advanced, really good calculator. It’s a mechanical device mated with an onboard computer of sorts, and all it does, all it’s intended to do, is to measure changes in air pressure and calculate those changes into descent rates (altitude) and speed (climb or descent speeds). Then, it really has only one decision to make, decide if those calculations meet or exceed a predetermined descent speed at or below a predetermined altitude, and if YES, then the unit will initiate an activation. The problem, if you will then, is that skydivers are capable of putting their AADs in scenarios that generate unintended activations with their deliberate actions, rather than in emergency life-saving scenarios. They can create activation scenarios through deliberate, purposeful acts.
Let’s look at a few examples:
The most common example of “burning down the house”, so to speak, is the swoop activation. We know without question that today’s modern high-performance canopies can generate speeds in excess of activation speeds for all AAD brands with standard “Expert or Pro” mode profiles. And as a result, every major AAD brand out there today now has some form of “swoop mode”, to prevent this activation scenario from occurring. Yet, year after year, we still see swoop-related AAD fires, some resulting in severe injury to the jumper. We know this can happen, yet it continues to happen each year. How then does this continue to happen? Typically, it’s simply that the multi-mode AAD is set in the wrong mode.
I wish there was a way to sugar-coat that statement, but there really isn’t. It’s become an unfortunate growing trend these days to turn on an AAD but not wait until it finishes its set-up sequence to verify that it is in the correct mode, before moving on to something else.
Jumping an AAD in the wrong mode causes accidental activations every year. And it’s not just swooping. I was recently shared a story by a good friend that had an AAD activation after an AFF instructor jump. His AAD was still in wingsuit mode, and as he spiraled down to land, he initiated an AAD fire. Thankfully he was okay. But the results could have been catastrophic.
But let’s get back to the story at hand. As new jumpers enter the sport, from a training perspective, we tend to learn at first the “need to know only” to save our lives. We learn to turn on the AADs, but rarely do we get exposed to the inner workings so to speak, because we are under highly supervised situational control from our instructors. And as we get better and progress onwards to becoming licensed skydivers, we take on more and more responsibilities of our gear and our gear knowledge. As it relates to AADs, we learn more and more about their modes: student versus expert/pro, activation altitudes and activation speeds. We learn that while every AAD out there has similar activation parameters, they are all slightly different. But not everyone walks away with the same understandings of how their AADs work, or at what point the full responsibility of knowing how your AAD works, falls on to the new skydiver as they progress.
If we look at the causality of the incident described above, it can be summarized as a lack of understanding of the parameters of the AAD being used, in this case, in student mode, by the user.
The key point here is that this information is readily available by all AAD manufacturers.
We just need to know:
- that it exists
- where to find it: in the manuals, and
- that it is our jobs to know the parameters of the gear we use.
Point 3 is the most critical, as we (the sport skydiver) are the sole stakeholder in our own safety when we put a parachute system on our back.
Student Mode (Under canopy):
- Vigil: 1,040ft – 45 mph
- Cypres2: 1,000ft – 29 mph
- M2: 1,100ft – 29 mph
The unit used in this case study was an M2 AAD. If we then look at the jumper’s initiation altitude of 1,200ft to start the steep speed building turn, and apply the activation window altitude of 1,100ft which exists all the way down to 195ft, then it becomes clearly visible how and why this activation occurred. If we then go to the M2 user manual – page 7, not only do we see that is the activation altitude for Student Mode is clearly available, but immediately following this data, we see the statement:
The speed of approx. 13m.s-1 / 29mph may be also reached with a fully functional parachute!
I asked this jumper for permission to share this story as I felt it would be a tremendous learning opportunity for our community, and the jumper wholeheartedly agreed. To their credit, they are allowing me to share this story, and I both applaud them and respect them for that. If even only one person opens their user manual for their AAD after reading this, whether they own the system or are borrowing or renting a parachute system, then this story will be a success. If we can keep one person from burning down the house so to speak because they have a better understanding of how their AADs work, then we are better off for it as a community.
To conclude, as a community, we should address the continuing communication of gear knowledge, in this case AADs, as a vital aspect of continuing education in skydiving safety. As AADs evolve and progress, so too does the need to keep reviewing the parameters of the AADs we use. The worst tragedies we see in the sport are the ones we already know can happen, yet, repeat themselves anyways. Whether it’s a swoop AAD activation, a wingsuit mode AAD activation or a Student mode activation, they can all be prevented by simply understanding the parameters of the AADs that we use. Let’s all learn from this and go back to our AAD user manuals and make sure we have a firm understanding of the parameters of our units. If we don’t understand something, ask a rigger. And above all else, make sure you watch your AAD count down, each and every time to make sure it is in the correct mode you intend to use it in.
The days of “set it and forget it” are long since gone. Today AADs are complex multimode units designed to handle a wide spectrum of conditions and variables. If you use an AAD today, you are living in an age of “understand it and respect it”. To do anything less, is to subject yourself unnecessarily to an accidental AAD activation.
Stay safe up there my friends, and remember:
Knowledge is power. Go download your AAD manual!
AAD manuals can be found here:
Another interesting read on the AAD’s subject is about the decision of Raising your AAD Activation Altitude, by Johannes Bergfors.
Also don’t miss the change to review the nightmare incidents – what to do if the 2 canopies out scenario happens, by Lesley Gale.