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Hey WS BASEr

Is there anybody who has experience with big WS (V3/4-Venom; X-bird/2 Apache) and performance rigs (L/D2; TLs, Profile, Racer) inclusive lightweight Canopies?
Maybe there are people who flying there WS sometimes with “low profile” and sometimes with “normal rigs” (Zak, Perigee Pro, DP).
Is there a “real” performance increasing when wearing low profile rigs and big wingsuits?
If it’s so, how much? (%)

With performance, I mean speed or distance.

Thanks for info

I fly a V4 and own a LD/Trango and couple of "standard" rigs. Being a very mediocre WS pilot, I cannot tell a difference in the flight performance between the jumps where I fly my LD or my Hybrid with Troll. Can be, however, that if you can really max out the suit and fly it on the very high end of it's performance envelope, maybe there is some performance to gain on low profile rig as well.

What my point is that for the average pilot, there are far better and efficient ways to improve your flight performance than buying a low profile rig. For example get a GPS, get some coaching, go skydiving etc and practise.

Where the low profile (and lightweight) rigs do exel, however, are the big hikes. I have always calculated it so that if I'm hiking with my LD (compared to a regular rig) I can more or less carry my water and goretex jacket/pants "for free". :)

this is why i got UL gear. i'm nowhere near good enough to benefit from the small increase in performance.

ditto.

During the World Base Race 2011 Odd Martin (Tiger) was flying very steady with a time between 19:30 and 19:40 every race and jumping a BlackJack 260. In his last jump of the competition he switched to a low profile rig (Hybrid i believe) and his time was suddenly 18:66.

Not a huge difference, and it could be related to other stuff too, but it seems like increases are in around 0.5 to 1 second faster for everyone who switch during the 750 meter race. That should be about 2-5% performance increase in a race that measures maximum forward speed by experienced jumpers. For beginners and intermediate flyers there should be a lot cheaper ways to increase performance by 5% :)

The speed walking up the mountain on the other hand increases a lot more :)

Yes I can feel a difference, as far as % I am not too sure maybe if I ever have time I will go through the gps logs.

Some friends of me have low profile rigs (Racer/Trango – L/D2/Trango), but they don’t notice that there is any performance variation.
They were wearing “semi” profile rigs before. (Hybrid+Troll and Helium)
We all flying whit V4 but the distance we fly are the same. Speed difference -> I don’t know.
The Pressurised crew did some Wind tunnel tests with Tracksuits and Low profile rigs. There was no performance variation between the rigs. This applies only for Tracksuits, maybe for big WS and its attributes the performance will increase slightly.
So GPS dates would be helpful.

Likewise I just put a order in for the LD2 trango combo more so for the light weight feature being here it the rocky mountains over the winter I tend to have enough gear to keep warm on the hikes and in case you gotta stick it out in some nasty weather... and just means now I got two rigs so I don't rag out my vtec Flik quite so much on the terminal jumps :-)

The ridiculous thing is that I just realised my new wingy with all the extra stripes and colours splashed about probably has an extra 1/2 kilo in weight as more of a fashion statement than anything else. So now I am carrying a lighter rig but a heavier wing suit? So something to be mindful of I guess? Sometimes looking cool is not so practical haha

Can't say about big wingsuits (V4, which I only jumped with Razor/Trango), but when I transitioned from DP to Razor while flying Phantom 1, there was definitely about 7% improvement in max L/D. With DP, my L/D was topping at about 2.1-2.15; with Razor, it topped at about 2.3. These results were obtained using L/D Calculator in Wingsuit Studio.



P.S. Whether you can notice a 7% improvement in flight, is a different question. It's definitely there when measured (and perhaps can be helpful on those flights where max L/D is a matter of clearing a distant ledge, or else pulling early), and there's a different feeling of rig when flying, but I doubt this feeling comes from 7% difference in performance, I think it comes simply from a lighter, more comfortable brick on your back and slightly lighter load on your arms.

Prevyet Yuri-

With any due respect, the cheapest + best way
to improve the glide ratio of an American is for
that jumper to exercise and eat healthy.

Since their height is a constant, less weight
and better strength will improve their L/D
plus the extra cardio helps them get more
jumps, and we all know experience helps.

Not necessarily. Higher wingloading -> faster speed -> higher Reynolds number, and I believe higher Re leads to improvement in L/D. Also, faster speed -> higher ram air pressure -> smoother, more rigid wingsuit -> better L/D. Also, faster speed -> better penetration against the wind. Also, more weight is usually accumulating in upper body -> center of gravity is higher -> better balanced wingsuit, more power in it, less stally. And finally, faster speed -> more excitement in flying.

So it's smart to have some extra weight!