I recently read the posts from Wayne Stout regarding his beliefs about the cause of his son's death. There were some very basic inaccuracies in his statements regarding equipment. This is understandable given that he is not a parachutist.
However I was concerned that many of the jumpers who posted in response accepted these inaccuracies without debate. Only a handful of people (Yuri, JJ, Doug and a few others) pointed out some of these inaccuracies. This indicates a very low level of basic knowledge about the equipment used in this sport. Lack of knowledge in this area is extremely dangerous and I feel it needs to be addressed. This post is meant to educational in nature, not a criticism to Wayne.
To address some of the points made:
From Wayne Stout:
>> Two of the major manufacturers of Base
>> equipment have internet
>> sites with training information posted for their
>> clients. Both of these
>> sites would suggest that Brian was dead before
>> he walked out on that
>> bridge to jump with the other 7 jumpers.
>> Brian was using a 38" Pilot Chute, a 6'9" Bridle,
>> went stowed, and was
>> assigned a 1-2 second delay for deploying his
>> Pilot Chute. Any one of
>> these factors alone would not be a major cause
>> for alarm - all of them
>> in tandem were a death sentence for Brian.
In order to address this it is necessary to first outline the different stages of deployment from p/c release to full canopy inflation. The example given here is for a slider removed square (phase 1-6) or for a round canopy packed without a diaper (phase 1-5).
Phase 1: Pilot Chute (p/c) is released
Phase 2: p/c reaches bridle stretch
Phase 3: p/c inflates
Phase 4: p/c extracts canopy to line stretch (there are multiple sub-stages here such as container opening, extraction of canopy from container and lifting of the canopy to line stretch)
Phase 5: canopy achieves bottom skin inflation (there are multiple sub-stages here)
Phase 6: canopy achieves cell pressurization (there are multiple sub-stages here).
The manufacturer’s recommendations for p/c size are in regards to Phase 4 only: the speed of canopy extraction.
In regards to this incident, the fatality occurred because a malfunction occurred at Phase 3 (p/c inflation). The incident had nothing to do with Phase 4 (speed of canopy extraction). The manufacturer's delay/pc size tables are therefore not relevant to this fatality in any way.
***
However on a side note, the usage of a 38" p/c at delays of less than 2 seconds is very common and very tested (often because people do less of a delay then they plan). Canopy extraction will take slightly longer (perhaps 1/3 of a second longer) at a 1.5 second delay than a 42" p/c and about 1/2 a second longer compared to a 48" p/c at this delay range.
These extraction time differences only become critically relevant when the exit altitude is extremely low (e.g. sub 230’) or if the landing area is distant. In regards to something in the height range as the Perrine Bridge (486') the p/c sizes commonly used (in the 38" - 48" range) is more relevant in regards to other issues such as center cell stripping.
A 38" p/c is probably the second most commonly used p/c at the Perrine Bridge (after the 42" p/c). I know one major gear manufacturer that prefers to use a 38" p/c at the Perrine Bridge with 2 second delays despite the extraction speed recommendations on that persons website.
I doubt that any knowledgeable gear manufacturer would state that a 38" p/c is unsafe or unwise to use with a 1.5 second delay from 486' given the landing area options of the Perrine Bridge. This pc size/delay combination has been used thousands of times and will continue to be used by the BASE community.
***
In regards to Phase 3 (p/c inflation speed), the opposite is in effect compared to Phase 4:
In general, the smaller the p/c the FASTER it will inflate.
The same logic works for round parachutes: for example a 19' diameter round canopy will generally inflate faster than a 26' round. This is common knowledge.
The fatality at the Perrine Bridge occurred because the p/c failed to inflate. In regards to p/c inflation alone, a 38" p/c is more reliable than a 42", 45", 48" p/c (or whatever size some people think should have been used to avoid this fatality).
The size/delay combination used by Brian is acceptable and commonplace in the sport of BASE jumping provided minimum exit altitudes are adhered to.
In summary the diameter of the p/c used in this incident was not a factor.
Another point of clarification to Wayne Stout:
In BASE jumping, the term "delay" refers to the time period from leaving the exit point to releasing the pilot chute. Many non-BASE jumpers make the incorrect assumption that delay refers to the time period from leaving the exit point to line stretch (or the commencement of deceleration).
Wayne stated that Brian was previously taking 3-4 second delays at the Perrine. A 4 second delay with a round canopy at the Perrine results in an extremely low deployment. (I have seen people hit the water hard, without fully pressurized canopies, doing 4 second delays with slower opening rounds).
For someone of Brian's experience level, a 4 second delay from the Perrine Bridge with a round canopy would be extremely dangerous and reckless to say the least. Even a solid 3 second delay with a round canopy of Brian’s make would have resulted in relatively low openings for someone of Brian’s experience and would have raised a few eyebrows.
The delays I (and others) witnessed Brian performing prior to his death were all around 2 seconds, which is about 3.5 seconds from exit to line stretch (I think this is where the misunderstanding lays). 2 seconds is a very common delay at the Perrine (despite many people's claim that they did a "3").
For Brian’s participation in the multi-way he was asked to do EXACTLY what he had been seen doing before: About a 2 second delay. He was surrounded by the most experienced jumpers and given the best spot to exit with a round (above the center of the river). He was not asked to do anything different in regards to his individual jump. He was responsible for the working order of his own equipment.
Length of the Bridle:
No-one (to my knowledge) knew that the length of Brian's bridle was not standard until after the incident.
As Doug pointed out in a previous post: The people on the multi-way did not teach Brian, they were not responsible for his training, his packing techniques or his gear configuration.
If I had been aware that Brian was using a bridle of that length I would have voiced my objection to it (simply because it is not adequately tested in the BASE environment) and offered to loan him the spare one I always carry around (I have done this in the past). However in this case, I do not believe it was a contributing factor in the fatality.
Before people are quick to criticize Brian or his instructors for not checking the length of his bridle, how many of us have actually taken the time to measure our bridles (or the diameter of our pilot chutes)? I own a bridle produced by a major US gear manufacturer that is less than 8’ in length. I used it about 120 times before I actually measured it. Few bridles out there are exactly 9’ in length. Pilot chute sizes are often even worse in variability.
However we do know that bridles of 5-6 feet in length work well at terminal velocity. This is because the majority of bridles used in skydiving are 5 – 6 feet in length (measured from pin to p/c attachment). The greater the airspeed, the longer the burble that trails behind a human body. By this logic we could surmise that a bridle of less than 5-6 feet in length would clear the burble and work at sub-terminal airspeeds (if it had enough snatch force to open the container). By this summation Brian’s bridle length was adequate.
A p/c caught in a burble or affected by turbulence wake is usually highly unstable (it bounces around erratically). The video review of Brian’s fatality shows the p/c in tow to be highly stable at bridle stretch. It does not exhibit any of the known characteristics of a p/c being affected by the burble or in the turbulence wake of the jumper.
The bridle was 6’ 11” long (however when attached to the p/c and shrivel flap by larks head knots the bridle length decreases by about 2 inches).
As stated before, the industry standard bridle length for BASE jumping equipment is 9’.
One BASE historian states that the greater bridle length (compared to skydiving bridles) was originally invented to generate adequate snatch force to open pin closed skydiving containers in lower airspeeds, not to clear the burble (which is a common misconception among BASE jumpers). 12’ bridles were originally used and then this was later reduced to 9’ when Velcro rigs became popular (as the shrivel flap component added about 3’ to the system). The industry standard length of 9’ bridles in BASE does not hold any real validity, other than 9’ works and does not cause any known problems. Other bridle lengths have not been adequately tested in the sub-terminal BASE environment to make any conclusions about their suitability or reliability.
According to various sources, the average human body in a box position at terminal velocity will generate no more than 5 feet of burble. The length of the burble decreases at lower airspeeds. Turbulence wake extends further than the burble however pilot chutes do not have a history of failing to inflate in turbulence wake (as seen in skydiving).
In summary, although Brian’s bridle was not industry standard in length, there is no evidence to support the fact that this was a factor in the fatality. Once again, the p/c did not exhibit any of the known characteristics of a p/c being affected by the burble or in the turbulence wake of the jumper. The p/c demonstrates characteristics of being towed in clean airflow.
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Some more random details in regards to the 8-way (I detailed most of the organization of this jump in a previous post).
The 8-Way was born when a member of the Arizona group (that Brian was with) wanted to organize a big way to take photos. The load was primarily going to be members of the Arizona group. I was asked if I would assist in the planning of it. I replied that I would do so and also stated that I wanted to be a participant. I said I didn't have time to organize who would be on the load (as I was packing and rounding up BASE jumpers is “like herding cats”). When it came time for my role in the multi-way (assigning the line order and delay's) I was presented with 7 people - one of which was Brian. He was the only person from the Arizona group. His rig was packed at this stage. Given his low experience level I asked him to do exactly what he had been doing in his previous jumps. Another low-experienced Arizona jumper approached me to be on the multi-way (this would have made it a 9-way), however because he was jumping a square I asked if he would not participate (I was worried about canopy collisions). Brian was not an issue in this regard because he was jumping a round. None of his instructors or colleges voiced any objection to him being on the load.
My point is that Brian wanted to participate on the 8-way. He seemed pretty excited and intent on being a participant on it. He performed his role well (nice exit, stable body position and pitched at the right time). If he were alive and willing I’d ask him to be on future multi-ways.
People have made points that he was “over his head” by being a participant. I disagree. Although being on the 8-way would have placed him under more stress than a solo jump, I don’t think it was more stress than he would have experienced on his first cliff jump (as he was planning on doing several days later). Probably less stress than he would have experienced on his first illegal building jump (if he had ever chosen to go down that path). Also he definitely was not “over his head” as much as someone who is about to attempt to do their first aerial without any prior training (something that is common place at the Perrine). Nevertheless, the decision to participate was soley Brian's and nobody else objected to it.
For this fatality we do not have enough evidence to conclusively state the reason. Given what we do know, I feel we can safely rule out the pc size / delay combination and place the bridle length in the “highly unlikely” category.
My full respect and condolences goes to Brian’s family. In my personal experiences loosing a close friend is difficult enough. I can not even imagine the horror of loosing a child. That is something no parent should ever have to experience.
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