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Poll: Your Average Fallrate

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First of all, I'd like to apologize for cross-posting, but I wanted to make sure I reach those only reading the forum of their specific interest.

Maybe you can help: I'm trying to figure out more accurate fallrates for the different disciplines. With all those ProTracks out there, it should be possible to collect a wide sample of average freefall speeds and to calculate an overall avergae freefall speed for the different disciplines.

So, I'd really appreciate if you could state your average fallrate for the different jump types you do, based on your ProTrack readings (TAS), e.g:

RW: 120mph
Freefly: 180mph
Speed: 250mph
Wingsuit: 80mph

I'll summarize and post the results later.


Thanks for your help!
Klaus
My Logbook

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Why do you want TAS? not SAS
people jumping in Colorado where the ground is
5000' or so above sea level will record higher speeds
than the same person jumping at Perris near sea level.
the whole point of SAS is to level the playing field.

Andrew
B|

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Why do you want TAS? not SAS
people jumping in Colorado where the ground is
5000' or so above sea level will record higher speeds
than the same person jumping at Perris near sea level.
the whole point of SAS is to level the playing field.

Andrew
B|



TAS has a precise, scientifically defined meaning. SAS is just an invention of L&B.
...

The only sure way to survive a canopy collision is not to have one.

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Your average TAS drops throughout the dive. How can you say?



So does your SAS. Just give me an average fallrate, SAS/TAS, whatever makes you happy...

I expect the difference between SAS and TAS to be less then the median deviation of the results I'm getting of this poll...

If you want to assure proper numbers state SAS as well of elevation of your reference point and
ground pressure, as well as an height, pressure and temperature profile of your jump.

Whatever you do, just post your average fallrates...

K.
My Logbook

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Let's try to get back to the original topic: Please post your average fallrates for the different jump types you do, based on your ProTrack readings, e.g:

RW: 120mph
Freefly: 180mph
Speed: 250mph
Wingsuit: 80mph

Please state SAS/TAS, whatever makes you happy...

I'll summarize and post the results later.

Thanks for your help!
Klaus
My Logbook

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Have you read Gary Peek's report? He did a bunch of jumps with an electronic barograph and made the results available. Many of the jumps have TAS readings, and they all have "SLAS," sea level airspeed, readings. You probably want to keep in mind that Gary is a big guy, so his speed on the solo jumps might be on the high side.

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Even within flat RW it can vary by quite a bit.
I've found that zoo l/o loads sometimes get as low as 110 mph TAS and people -still- wonder why somebody went low. DUH! L/Os listen up, pick up the pace and you'll have fewer people going low!
Slow 4-way in my experience is maybe 118ish, average 4-way is about 120ish and fast 4-way maybe 125ish. It seems to me that the better teams also prefer slightly faster fall rates. I've shot 4-way teams as fast as 135, fat boys though.
My straight down belly range in camera suit is about 98 to 135ish.
5'11 and 235 out the door.
Me in a tracking dive, sweater, BDU pants is about 104.
Me in a tracking dive wearing camera wings is about 90ish.
Me in a sit, sweater & jeans is about 155 to 160.
quade -
The World's Most Boring Skydiver

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Those are all TAS (didn't I say that?).

Anyway, I happen to like TAS because to me, it makes a bit more sense, but I also understand why some other folks like SAS.

TAS is the calculated True Air Speed based on the rate of change in pressure over the time of the freefall samples being taken.

For "Speed" skydiving competitions TAS is used on a leg mount.

SAS is Skydiver Air Speed and is an invention of L&B. It is their attempt to "normalize" the exact same information that was sampled in their TAS calculations but recalculates it as if the entire skydive took place at 4,000 feet above mean sea level on a "standard" day.

There are several advantages of this -- the key one being that in theory you can compare fall rates independent of the DZ you happen to be at.

The problem is that ProTracks don't seem to be mounted uniformly on all skydivers. Some skydivers have their ProTracks mounted on the outside of their helmets and some have them mounted on the inside of their helmets. Well, this is a pretty big deal because the main variable in the SAS calculation is the air temperature. Obviously a sample taken outside a helmet and inside a helmet are going to be quite different.

Anyway, I've been keeping track of my fall rates on a ProTrack for a couple of years now and I record them in my logbook as well. I've gotten pretty good at being able to tell how fast the group I'm shooting is going without even looking at it now. I'm usually not more than 1 or 2 mph off what the ProTrack says, which I think is pretty good since that's just about the limit of the accuracy of any two ProTracks when compared to each other anyway.
quade -
The World's Most Boring Skydiver

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Hi. Check out Speed Skydiving results at www.hangout.no/speednews. Results are in kph. Males on the left. Females on the right. By the way, we have quit using the leg mount and have been, since November 2000, using the average between two Pro-Tracks, mounted on each side of the hip. The resuls on the top are the best scores in competition since Nov 2000, and the ones below are the best from the 2002 World Cup series.

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