Rooster ShadowBox

tinyE · Since 21 Jan 2006 2004 Posts not really an XTreme Poster

Hey guys,
The SB guy sent me this story...figured it was fitting to post here.

Yesterday I met with Shawn Coleman at Rooster Rock....and as you surely know, it was nuking. The entire beach was moving in the wind! Anyways, Shawn used the ShadowBox and his best recorded jump was amazing at 50.0 feet high, 235 feet of distance, a peak speed of 72 mph, upward g lift of -9.6 g's and 6.9 seconds of hangtime. Unreal. Attached is a shot of that jump. He came in after 15 minutes and had recorded a jump of 42 feet....and went right back out to beat it.

Nak · Wed Sep 23, 09 7:38 am

OK, I hate to be a disbeliever, but 9.6 Gs... No way. I have a little experience dealing with a high G environment from my USAF days. I've never seen anything in kiting that would lead me to believe that anyone was ever getting even a little close to that. MAYBE a momentary 3g pulse...

Assuming Shawn weighs 150#, the load on the kite would be almost 1500#!! If he's using 600# test line, both front lines would snap unless he was holding down 300# with the bar. Even if he was, any imbalance in the loading of the kite, like it turning, would snap a line.

At 3 Gs, you have to start an anti-g straining procedure to stay conscious. At 5 Gs, most people need a G-suit in addition to using the anti-g straining procedure. The F-16 has a reclined sitting position to allow pilots to pull 9 Gs. A kiter in a standing position will be more vulnerable to G force than a seated pilot. These examples are for a sustained G load, but even a very short time at 9.6 Gs is going to black you out.

I'm just saying...

Mark · Wed Sep 23, 09 7:45 am

Shadow box is mounted on the board. Could it be measuring board swing or leg kick to get those crazy G force numbers?

Spike · Since 13 May 2007 1414 Posts Alameda Spelling Expert

perhaps the impact on the water could be a 9G load to the board.

Kraemer · Since 24 Apr 2006 1736 Posts Sky Pilot Unicorn Captain

I'm sure it was a death defying dangle; at 72 mph however; he would be the world recordholder would he not?
7 secs sounds about right; but getting to 72 and back--wow

Nak · Wed Sep 23, 09 8:02 am

OK, forgot to add: WOW. Amazing damn jump!!! Thumb's Up

genek · Since 21 Jul 2006 2165 Posts East Po KGB

The height is cool, but the other numbers don't mean much unless they're measured properly.

I talked to the shawdowbox people last Thursday and they agreed the speed number is meaningless unless you're quoting the speed averaged over some time that doesn't include the jump. I rode in the Hood River on Thur and hit a max speed of 52mph on my boot board without fins. I'm pretty sure I wasn't near breaking the world speed record and they said it was probably the board rotation or jerking during a jump that caused it. I'm guessing the Gs are measured in the same way and just represent the jerk of the board not the rider.

forrest · Wed Sep 23, 09 8:20 am

Perhaps we can see a diagram. I know shadow box has some software to display the ride.

tinyE · Since 21 Jan 2006 2004 Posts not really an XTreme Poster

I got some info from ShadowBox:

Speed: This is an instantaneous measurement, it could have been for only 1/600 th of a second. Most likely an edge speed of 30 and a quick flick of the board. This stat is pretty meaningless and will be changed, but is not inaccurate.

Gs: This is the landing impact and is not unreasonable at all. This is also an instantaneous measurement and not a sustained acceleration.

The Sbox is measuring momentary readings, not sustained readings. As the above poster correctly stated, most people would black out if they experienced sustained G forces of over 3-5 g's over any stretch of time. However, even in the sport of wakeboarding, momentary positive g force ratings of 8 g's are experienced when landing in the flats after a big jump, and big negative g force readings are found during the moment of the pop. These are of course just pulse readings. In kiting, when the board accelerates upwards at such a rate, this also does not mean the kite is also doing the same vs. the person (thus the correct line tension/breakage question). The Sbox has simply measured a momentary pulse of upward acceleration of the board.

The ShadowBox is being changed to reflect sustatined speed over 3 second intervals, so it doesn't reflect meaningless, pulse speeds. The G-force readings will remain but we will likely create three categories: Landing Impact (in G's (which is the pulse)), Max Upward Acceleration (in G's (which is the pulse)), and Max Sustained Acceleration (in G's, over a 3 second interval)).

Thank you all for this feedback as we work to perfect the ShadowBox for kiting.

also,
these readings are just for the board. So on the landing your knees and body reduce your acceleration to much lower levels, but the board smacks the water and does see these accelerations.

Same for the speed, your center of gravity doesn't see that speed but as you do a rotation the board sees much higher speeds. An analogy is a baseball pitch, where your body doesn't move but your arm goes to 100 mph plus.

lastly, there is a way to view it... and it's pretty cool to do so. I'll ask if he has the ride files and I'll post an export out so we can take a look at it.

Kataku2k3 · Since 14 Aug 2005 3754 Posts PDX-LA Videographer

Amery had it on his board yesterday and I swear the readings aren't correct, even for height... Dunno though, maybe we're just bad at judging height from the beach? Displayed his max at like 28ft (but then some compensation of +4ft was supposed to be added to that).

NateDogg · Wed Sep 23, 09 9:36 am

Boost party!

I think that's Shawn Richman though, right?

tinyE · Since 21 Jan 2006 2004 Posts not really an XTreme Poster

yah, he sent a correction,
shawn Richman

C Johnson · Since 17 Apr 2009 854 Posts Seattle Opinionated

I believe the high impact G's

I've had 2 gopro cameras launch off my board. one failed the adhesive mount and the other was a surf hero mount which has a huge surface area of adhesive so instead of the adhesive failing it just shattered the plastic.

both landings were pretty standard. nothing super hard and nothing super soft either.

the first time, when the adhesive broke, the camera just popped and rolled off the board into the water. but! when the surf hero mount failed. the camera actually shot a good 15ft at least up into the air and and I lost track of it for a couple seconds until I finally spotted a splash a good 25ft down wind of where I was riding. I would think the amount of force required to do that should be several G's easily.