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Curious if anyone knows how many g you pull on a BASE jump opening (terminal and slider up)???

That's a pretty loaded question. The G's are just Acceleration. In this case negative acceleration, also known as deceleration.
So you have to determine how long it takes to slow you down. (v1-v2)/t

And the variables are incredibly diverse. You ask "terminal and slider up". What kind of slider, what kind of canopy, what is your terminal velocity? Are you factoring in a forward vector like in a track?

It has a lot to do with how you pack and what gear you use; so you would have to make an experiment and test a theory by jumping. You could probably analize the jumptrack data from Protrac on a skydive?

So, to answer your question, No I don't know. But my Engineering brain got away from me there for a few minutes.
For now I like using terms like "spanked" and "rocked". I also like "instant canopy" and "jesus titty-fucking christ" to describe my brisk openings on terminal jumps.

-Bill

At some point in time this year, I'm going to strap on our $9000 accelerometer and find out the opening shock G's for BASE jumps. The main obstacle is to keep the accelerometer tight against my body so it experiences the same shock as my body. I've used this accelerometer for numerous package and parachute drops and the results are often surprising. So stay tuned....

There is an old thread asking the same question about skydiving canopies.

As I said in that thread, if you are curious about what sort of potential damage an opening can do to your body, I think jerk (change in acceleration per time), in addition to max acceleration, is important to know. A high constant G loading alone is not very damaging, I don't think. It's the rapid onset of a high G loading that will get you.

If the original poster was not actually interested in "damage" numbers, then I have gone off topic.

Personaly, I think that the rapid re-orientation (as in belly to hanging, or some disgusting emergency off axis deployment.) of a persons body while the parachute is opening is more destructive than the actual "G" force that a body experiences. I believe this is the reason for people getting neck injuries from 4plus second slider off deployments.
Not saying it doesnt happen sliderup as well, just my opinion.

I have done 7 plus Gs in aerobatic airplanes for as long as 2 seconds. No Gsuit, and really, 2 seconds is the limit for that. Ouch. But 7 Gs decelerates a human body at 70m/s^2(ish) seriously, if we are not going from 200km/hr to 20km/hr an less than 15mterers, i doubt that Gforce has anything to do with it. take that either way.

I think spine compression has a lot to do with something like 200 to 20 in less than meter.

Cornishe is packing a reserve in our living room and he says that if you put the accelerometer up your ass you will get the best reading. I thought maybe the helmet would be good, but center mass would give the best readings.

Oh, and feel free to haze him because he wears scrubs to pack reserves... what a freek

-Bill

That seems pretty pricey. My home built g-force data logging system costs less than $400 and less than $200 for the reduced version. Will keep the community tuned in...

ONE MILLION Gs, last I checked my own anal g-meter.

I'm gonna start refering to myself as a "G-man," with the G standing for gravity.

Sweet, and I'll be the A-man, with A standing for ass.

We used to call a friend assman, especially when there were women around. We called him that because he always managed to land on his ass when he base jumped. You should have seen the women clear, as if they could outrun Carl Lewis, when we would say "hey Assman!"

Just speaking about high G exposure....I do 9 G's at 15 second intervals groudning out to 5 G's for 15, then a rapid to 7 for 15 and so on and so on. All without a G suit and its fine on the body with the proper AGSM applied. The only damage my body has experienced are the random G-easles I get from busted caps. from the damn seat in the fuge, but rapid onset and vice/versa to high G loads is ok......at least in my experience.

I also believe the ejection seat trainer puts you at around 18 for a sec. but I could be off a little. Cant remember the exact G load on that thing.

Yeah, im kinda jealous. My planes are a citabria and A Christian Eagle. my accelorameters only go to 12, the Citabria breaks at 9 and the eagle at... well, i dono redline reads 12, but its always more than that. more than i can take right now.

I agree that instantaonious gs are much easier to stay consious for, im not quite sure on the actual measuments, so i withdraw my statement. I am pretty Competent at physics methinks. but i agree about your points.

Im no pro aerobatic pilot...

Dont crash

Some years have passed. Update? :)