bag lock or strip due to safety stow

[darnknit 0]

does anyone know of a specific incident where a fatality occurred that was directly attributed to either bag lock or bag strip on a reserve equipped with a safety stow freebag? someone i know has alluded to this, others i know think it is a lie. i have just searched my memory, dz.com incidents forum, and a skydiving fatalities web page, but i can't find a single incident directly attributed to the safety stow design. can anybody help me find these incidents? here is what i was given to work with:

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Like I said I have seen a fatality caused by a bag lock wherein the bungy didn't break, and it would have if it had been a rubber band. I've also seen the fatality wherein a line/bag strip blew most of the A lines off of a reserve canopy, and the other fatality wherein the bag stripped off of the canopy leaving it in the reserve container tray. These three fatalities that I know of are just off the top of my head.

if anyone could help me find dates, locations, and gear related details of these incidents, it would be helpful.

blue stuff,
p.j.

pulling is cool. keep it in the skin

[PhreeZone 14]

?????


Date Location Category Age # Jumps AAD?/RSL?
8/27/1999 Calhan, CO DMAL 42 2200 N/N
Description: This jumper experienced an unidentified, but high speed, main malfunction after videoing a tandem, and executed his emergency procedures. The malfunction may have been only a pilot chute hesitation (He rolled belly down, pitched, waited 2 seconds, look left and right, then went fort then handles), judging from the first-person video. The reserve opened hard, breaking three lines at the attachment point to the connector link on the right front riser. Those lines cascade into 6 A-B lines, so he was largely missing 1/4 of the parachute, resulting in a (probably fast) spinning malfunction. The parachute spiraled into the ground in an unlandable configuration, killing the jumper. He had made all his jumps in an 8 year period, so was probably quite current. This was his second jump of the day. Video shows the main just after the cutaway, neatly inflating, trailing an inflated pilot chute.
Later video analysis indicated that the reserve was flying relatively okay until the deceased released the brakes on the reserve; then the reserve went into a spin .

The reserve in question was a Raven I, 181 ft^2, with a placarded maximum exit weight of 185lbs and a max deployment speed or 130 kts. The DZ elevation was 6450, with an opening altitude of 8500-9500msl. The jumper's exit weight was approximately 285lbs.

Lessons:While it might seem easy to berate this jumper for failing to stay within limits on his reserve canopy, many many skydivers exceed their canopy loadings by a similar percentage. The higher field elevation increases deployment force, as did the high deployment speed. This is under investigation by the manufacturer. This incident implies it may be a bad idea to release brakes on a partially damaged reserve canopy.



Date Location Category Age # Jumps AAD?/RSL?
6/3/2000 Lake Tahoe, CA MAL,DMAL 43 356 Y/Y
Description: The deceased was from another drop zone and was doing speed dives all day. The Pro-Track indicated that on his final jump, he did two attempts for speed, reaching about 300 mph, and then went for a third on the same dive. During this attempt it appears that he lost altitude awareness. He flattened and pulled his main which appeared to have a pilot chute in tow malfunction. He was using a bungee-style pilot chute. Almost immediately, probably recognizing his low altitude, he fired his reserve. Still traveling faster than normal freefall, his reserve slammed open at 1000', breaking 4 lines. The 2 center cell A-lines, the right center cell B-Line, and a right C-line second from the end all failed at the line attachment bar tack. A two-foot section of the right load-bearing rib (second from the end) failed at the D-line attachment. The broken C-line entangled with the right control line producing the fatal spin. The right rear grommet on the slider showed damage (it was partially pried open) suggesting that the slider was involved. The outboard right A-line attachment was damaged but did not fail. He then tried to fly the canopy all the way until impact. He was med-evac'd from the scene. During surgery on his ruptured spleen, he died of internal bleeding. He had other injuries as well, including a collapsed lung and a torn aorta. He weighed 225 without gear and was jumping a 181 reserve. The ProTrack indicated his airspeed at 145mph at pull time. His reserve was rated to 172mph and 202lbs; he was therefore significantly overloading the reserve, by perhaps 25% of the rated loading. Witnesses report the reserve, when it opened, sounded like a cannon going off. His CYPRES was on and did not fire. One witness reports that he had mentioned that his altimeter was not functioning well at high speed -- this has not been corroborated.
Lessons:A nominal estimate of this person's exit weight is 250lbs; this is significantly over the maximum rated weight for the reserve. This excessive loading was the likely primary cause of reserve failure. There are two secondary issues. First, the higher-than-normal deployment altitude (Skydive Lake Tahoe is located at 4960'MSL) places greater forces on the parachute at opening . Second, the slightly higher-than-normal deployment speed (145mph vs. 110mph) also increased the load on the parachute. It is also worth noting that "Speed" dives are a relatively new thing in skydiving. They present substantial new risks, particularly because gear is being placed into situations for which it was simply not necessarily designed. If you choose to participate in these activities, you should be aware you are taking additional risks. Keep in mind, at 300MPH and 3000ft, you are less than 7 seconds from the ground. Worse yet, you'll need to take most of that time just to slow down so that you can deploy without destroying your canopy or yourself due to the opening shock.

Yesterday is history
And tomorrow is a mystery

Parachutemanuals.com

[Hooknswoop 19]

Aren't both of those a result of the line attachment points of the Raven reserves and not the reserve deployment system?

Derek

[darnknit 0]

thanks PHREE,
i had found those incidents as well, i was trying to find incidents that were directly caused by safety stow design flaws.

pulling is cool. keep it in the skin

[hookitt 0]

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thanks PHREE,
i had found those incidents as well, i was trying to find incidents that were directly caused by safety stow design flaws.

Where does the report indicate a design flaw? I see a high speed deployment with a Raven reserve. If it was a Raven -M reserve prior to the service bulletin, then it's the reserve not the deployment system.

My grammar sometimes resembles that of magnetic refrigerator poetry... Ghetto

[PhreeZone 14]

Thats the only things I can find going back to '93 that involve a reserve system breaking. I don't see anything out there that is a Safety Stow caused problem. *shrug*

I remember rumors of the "freebag stripping" but I think it was a military jump or something like that. Its not coming up on any major search of the Fatalities DB's or my old issues of Parachutist.

Yesterday is history
And tomorrow is a mystery

Parachutemanuals.com

[PhreeZone 14]

I remember those, they were both -M's and were what prompted the SB.

Yesterday is history
And tomorrow is a mystery

Parachutemanuals.com

[mjosparky 3]

Both of these were the result of deploying the canopy outside of the design and test envelope of the the canopy. It is amazing how many people continue to do this today. But they all think they are different, it won't/can't happen to them.

Sparky

My idea of a fair fight is clubbing baby seals

[riggingplace 0]

***
I remember rumors of the "freebag stripping" but I think it was a military jump or something like that. Its not coming up on any major search of the Fatalities DB's or my old issues of Parachutist.

[riggermick 6]

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does anyone know of a specific incident where a fatality occurred that was directly attributed to either bag lock or bag strip on a reserve equipped with a safety stow freebag? someone i know has alluded to this, others i know think it is a lie. i have just searched my memory, dz.com incidents forum, and a skydiving fatalities web page, but i can't find a single incident directly attributed to the safety stow design. can anybody help me find these incidents? here is what i was given to work with:



Heard the rumors of a bag strip fatality back in the late 70's, funny thing is no one I have ever spoken to has actually seen one or has ever been able to produce a written report of one. My personal take on this is that it's skydiving urban ledgend. The rumor I first heard was that the "o' rings (pre safety stow days) had been replaced with rubber bands and by the time the jumper had to use his reserve they were rotton. Heard a few varients on the theme over the years but never a written conformation that it had actually happened.

The one concrete fact that the safety stow system has proved over many years and hundereds of thousands of deployments is that it is RELIABLE.

Mick.

• Quote

[JerryBaumchen 1,046]

Hi Mick,

That 'incident' (As it was told to me by someone who was there; they may not have seen the actual jump, though) is the one where one of the Golden Knights (on a style jump) took it quite low, apparently realized he was low & pulled the reserve. The pilot chute/bridle/reserve bag stripped and left the canopy in the container. The result was a fatality. This bag was an early Para-Flite with the butyl rubber 'O' rings. This caused (most of us believed at the time) Para-Flite to go to the Safety Stow.

That is the only case of reserve bag strip on a sport rig while used by a customer that I know of.

Hope this helps a little.

Jerry

[diablopilot 2]

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Aren't both of those a result of the line attachment points of the Raven reserves and not the reserve deployment system?

Derek

Id say both of these are due to opperating a reserve out side of its design limits.

The second fatality was not because of the landing, it was caused by the opening.

----------------------------------------------
You're not as good as you think you are. Seriously.

[UKFSDude 0]

could someone please be so kind and explain why opening a reserve at a higher altitude puts MORE force on the parachute on opening? I would have intuitvely thought that the opposite was true.

Marc

Everyone makes mistakes, just dont let them be your last.

[skydiverek 54]

Thinner air = faster freefall speed (airspeed) = air inflates the canopy fatser.

[RMURRAY 1]

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Thinner air = faster freefall speed (airspeed) = air inflates the canopy fatser.

=reason to avoid line dump on a small overloaded reserves.

[pbla4024 0]

So no air = opening is the fastest?

Fido

[UKFSDude 0]

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Thinner air = faster freefall speed (airspeed) = air inflates the canopy fatser.

apologise for the slight thread hijack but if the air is thinner then the pressure and hence drag exerted on the canopy fabric will be reduced. For me it then only follows to reason that this would cause the canopy to open more slowly given all other factors (e.g airspeed, temperature, atmosphereic pressure) remain constant.

Everyone makes mistakes, just dont let them be your last.

[Samurai136 0]

In thinner air you are falling faster, this results in a greater change in velocity (increased opening forces) in a high altitude deployment. It's been discussed before.

"Buttons aren't toys." - Trillian
Ken

[ernokaikkonen 0]

I know it's been discussed before, but I haven't seen a good explanation on why it happens. You go faster, yes, that much we know, but why doesn't the "less air to fill the canopy" offset the extra speed?

Any physics professors out there that would care to comment? With the math?

[Orange1 0]

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For me it then only follows to reason that this would cause the canopy to open more slowly given all other factors (e.g airspeed, temperature, atmosphereic pressure) remain constant.

But all other factors aren't constant. Kallend, who I understand is a physics prof, in this thread http://www.dropzone.com/cgi-bin/forum/gforum.cgi?post=1668217;search_string=density%20altitude;#1668217 says that your speed increases about 2% for every extra 1000' of altitude.

Skydiving: wasting fossil fuels just for fun.

[darnknit 0]

can you guys start a high altitude deployment thread so that i can hijack it to find out if there are any incidents directly attributed to safety stow design?

pulling is cool. keep it in the skin

[Orange1 0]

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can you guys start a high altitude deployment thread so that i can hijack it to find out if there are any incidents directly attributed to safety stow design?

sorry wonder if there any incidents directly attributed to thread drift?

Skydiving: wasting fossil fuels just for fun.

[rmsmith 1]

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I know it's been discussed before, but I haven't seen a good explanation on why it happens. You go faster, yes, that much we know, but why doesn't the "less air to fill the canopy" offset the extra speed?

In fluid mechanics changes in density are linear, but changes in velocity are exponential.

[pbla4024 0]

I don't think so. For air you should use Newton formula, which is linear in density and square in velocity.
F=1/2*Cx*rho*v^2
Keep F and Cx and you see, that when you have half preasure (rho is linear with p), you velocity is 1.41 times higher.

Fido

[krouton01 0]

Does anyone know what the cause of the Australian fatality was this year(Singapore guy). I know it was reserve problems and as I recall there was never any definitive answer given as to why. Some speculation to baglock I believe though.