Service Bulletin: Squirrel Stronglite Containers
1. Why we designed it this way, and why we were wrong
When we originally developed the StrongLite we wanted to make something very different. We started with the idea that the entire harness would be constructed from a type of webbing that is manufactured specifically for climbing harnesses. We spent some time at the load test facility with a climbing manufacturer, sewing and testing prototypes. They worked well, were very strong, and were quite different. During the testing of this lighter version we contemplated adding in the inlay strap that is now the modification outlined in the recent PMP, but the inlay was scrapped when we went back to Ty-8 materials and instead modeled the harness on the status quo, because after thinking about this lighter webbing for a while longer and testing the harness and thinking about how BASE jumpers tend to treat their equipment we decided that the durability concerns with lighter webbing were too great.
Back to the drawing board – with a Ty-8 continuous design. We still wanted to eliminate the heavy steel leg strap buckles, and settled on our current design which incorporates the light buckles without entirely relying on them and in terms of the riser-legloop-lower-confluence load path, is as strong as anything else on the market. We spent a lot of time thinking about how the leg loops and risers would be constructed, but not enough time focusing on the MLW wrap. The load testing that we performed on the Ty-8 version at the laboratory was very encouraging and we focused too much on proving how strong the harness was in normal configurations instead of imagining how a sustained (we tested momentary, which was not enough) load in the worst-case direction would affect the harness.
Knowing that our own testing could be viewed with suspicion, we also sent the finished harness to Para-Test Switzerland, for an EN certificate which is attached here. The EN testing is thorough but in hindsight not exhaustive enough. Please note that all tests in this report are with a 175kg (385lb) load and do include an inverted single riser pull which comes closest to approximating the angle that probably damaged the harness we are discussing now. It was our opinion that if it could sustain our tests and the EN tests at 175kg (385lbs) then it was acceptable, at least. Independently confirming the strength of the harness was important to us but we should have spent more time loading it creatively, ourselves. We should have paid more attention to the MLW wrap, not focusing enough on this section of the harness led us to what came next.
2. What our reaction was when it happened
When we received news of the incident, we talked to the jumper on the phone immediately after it happened, and began writing the first SB that was released hours after the incident. It asked jumpers to inspect their gear and report back to us, and to stop use immediately (No other Stronglites have been reported to show any sign of damage or wear). We sent a FedEx label on the 7th to get the harness back to the USA but it was only picked up today, the 12th (as of today, August 12, we still do not have the harness). The afternoon of the incident, Mike and I packed up the car and made the 7hr drive to the closest load testing facility. We spent the following day in the lab testing our production harness, versions of it, and other harnesses.
3. What we did to re-test
We repeated the inverted single riser pull that the EN tested. We tested this with the production version and other versions, and two different harnesses that we did not build. Video of the testing of our harnesses is here: https://vimeo.com/103272992 (password: load) We will not release video of the other harnesses that we tested – you can ask us to but our answer will remain no. Our harness is the problem here, not others.
The first test shows a production harness, then a version with double Ty-12 wrap, then production with a partial reinforcement, then finally production with the Inlay Modification described in the PMP we released on Saturday the 9th.
What we found was that while our harness admittedly fared worse due to our wrap material, all harnesses tested suffered the same type of damage at similar loads. Regardless of thread strength or wrap type, when the risers are pulled at such an acute peeling angle, there is only thread to take the load. Look at your integrated riser design – if you pull the risers straight down to your hips then the first thing that takes load is thread. The wrap obviously provides protection here and a weak wrap may tear or roll or both, but even the strongest wraps used currently “rolled” down the MLW as the diagonal peeled away. See attached photo.
One person has said that by testing other harnesses or mentioning that we did test them, we are “blame-shifting”. We sincerely apologize if this is the impression that anyone got from the SB or my comment above. Obviously, we have discovered a problem with our product – that has been evident from the beginning and we never denied it for one second. What we were quite surprised to learn is that there is also obviously this potential in other products out there, and we thought it was an important point to bring up.
As the news circulated, we heard back from other jumpers that this issue had already been reported to one other manufacturer, who did not release an SB or tell anyone at all. Secondly, the jumper who damaged our StrongLite wrote to us to say that his other harness, from another manufacturer, also showed signs of wear in this area. Take what you want from that, but I’m not sure it makes sense to use it as ammunition to fire back at us.
A note on the video, for our friend Matt Frohlich in particular: We shot this for internal use and our records only, it is not fancy or comprehensive. It was never intended to be released and I had no plans to publish it until it was claimed that we never actually tested anything, and probably just made all of this up. It is not edited in any way, it is just individual clips put together. When you see the machine back off and reverse direction, that means it has reached the end of the machine’s “throw” and the harness and chain need to be reset at a shorter chain distance to achieve more range and pull. It is not the operator intentionally backing off the load.
4. What we did to fix it
The inlay piece is a very simple 14cm (5.5”) length of Ty-8 added to reinforce the top of the 4-point at the MLW. It protects the top of the 4-point from a peeling load. Its strength approximates that of Ty-8 from any pull direction and is more than adequate to sustain the load while the jumper is rotated back to a normal upright position and the riser-lower-confluence-leg-loop path is then loaded.
Prior to implementing this fix, we discussed it at length with some of the most experienced riggers in the USA. Other ideas were talked about and the merits of a slightly weaker “bridge” of varying lengths and fastening methods were discussed. L-bars, steel rings to transfer load, etc, were all considered. We settled on the Ty-8 inlay because it meets the strength of the rest of the system, and if loaded will protect the 4-point while the jumper rotates back to a more parallel configuration.
We are replacing all StrongLites with an improved design that lengthens the diagonal, increases the wrap rigidity, and most importantly includes the inlay piece which prevents the 4-point from taking a peeling load in the first place. Every affected customer will have their replacement in the coming weeks. Mike is currently at our factory testing a series of samples to ensure that this improvement does what we want it to. This is an ongoing process and we are being as thorough and efficient as we can while also trying to keep not only our customers but also the BASE community informed. I’m sorry it took me so long to get this written but as you can imagine we have been rather busy.
5. What is happening now
Part of the conversations I had with another BASE gear manufacturer about this situation covered the fact that there is currently a negative divergence between the development of BASE jumping techniques and the type of gear. Jumpers are pushing the limits of the equipment past what was considered possible 10 years ago, and at the same time the market is demanding lighter and lower-profile gear. Head down BASE freeflying, high-performance tracking, canopies with more and more venting, all combined with jumpers pushing these limits of the sport with less and less experience. Publishing a more thorough examination of what exactly led to our harness being damaged might be seen as “blame-shifting” so I will not do it, but seriously, please, fucking think about it. There are two bottom lines: Most importantly, our gear had a weak point. Secondly, it was exploited in an extra-ordinary way.
This has, to be frank, been a brutal lesson for us at Squirrel and I cannot describe in words how grateful I am that the jumper was not badly hurt. I also cannot stress enough how seriously we take safety. I jump our gear constantly, my best friends are out there jumping our gear every day – so, for the most selfish and the most selfless reasons, we want it to be as safe as possible and a desire to improve safety in BASE is a large part of what drove us to start the company in the first place. We are a new company, and we are acutely aware of this. That is what led us to spend so much time load testing prior to release, paying for EN tests, having every single piece of load-bearing equipment that we ship inspected by riggers prior to shipping, etc. We take full responsibility for all of this and we will further deepen our commitment to safety and to imagining these worst case scenarios in order to better prepare equipment for them.
Sincere thanks to those who have been a part of the conversation behind the scenes, and to all of our customers.
-Matt
http://www.squirrel.ws
(edited to add attached photo - the EN test report pdf exceeds the allowable limit for attachments here, I'll get it put up at a link ASAP).
