Concern - Flicking

[Mac]

#131 Aleksei Irzhembickij - Feb 28, 2009 Aleksei Irzhembickij
Object: Antenna
Location: BELARUS, , Minsk
COD: Impact
Description:
Report from the Russians-

gusting winds changing from crosswind to tailwind measuring 18-22mph (8-10m/s)
the throw was clearly visible as a forward throw immediately after exit. The PC was inflated prior to the exit, and the jumper was not really able to throw. It seemed like right after the throw, the PC was blown behind the jumper. The PC was already inflated at the time of exit as he was holding it by the mesh. It was most likely unintentional as the jumper was experienced and new to throw instead of letting go. The container opened really low, he impacted right before complete linestretch, with lines partially out.

Witness Speculation : exit - inflated PC - sudden gust of crosswind blows the PC behind the jumper - jumper tries to change body position as he realizes something is amiss - the PC clears the burble, but it's too low.

I would like more detail on this fatality.

as the jumper was experienced and new to throw instead of letting go.

Actually I never throw....

I always exit with my PC able to inflate, and I just "flick" my wrist.

This write up suggests several things, so I would like more detail.

Thanks

Michael

[nicknitro71]

When holding the PC by the attachment point, partially inflated, without throwing, you are minimizing the effect of snatch force. Snatch force is related to the PC sudden deceleration. If there is little deceleration like in the case of the PC being already open, then there is little snatch force and you are relying upon the aerodynamic drag of the PC which can be easily canculated (see table). Snatch force can be calculated via simple differential equation models (see paper) as it is a simple system.

Now, with some PC, the drag w/out the snatch force is enough to open the container and extract the tarp, with others the opposite is true. My biggest PC is a 46 unvented z-po that never gage me an hesitation. I used to have a vented 46 that gave me several hesitation in go and throw situations.

I think in the end you have less chances of a hesitation if you throw the PC after about one second instead of flicking it as you leave the object. On the other hand, in ideal conditions, the latter technique should give you a higher deployment.

This jump happened in windy conditions. Windy slider down jumps are some of the most fucked up. Going stowed on such jumps is not wise. Go and throw on such jumps is not wise. Freefalling a 220' in no wind conditions with proper techniques might work every time...the same might not aply in windy conditions.

Carrying a static line with you could make a difference between walking with a smile on your own or not walking at all...they will call you chicken and gay but at the end of the day you will get to fuck all the bitches!

[Mac]

Nice one Nick, cheers

Michael