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see attached pic.
SL jump, or PCA planned.
the question I have is with a good solid push off, how many feet clearance would you anticipate with opening.
from the observation deck, it is 130 feet to flat level ground. there is a shorter roof (a) beneath the deck. what height would your minimun (b) height be to clear (a).
I did not give exact measurements of (a) or (b) more to stimulate opinions on distances/height and not focus soley on this jump.


pic now added. I am not gifted with computers

Post photo.

Would a direct bag with no bridle or pilot chute be a better option if you had an obstacle below that you were worried could snag something?

On a sl or pca you do not want a good push. You will have a pendulum affect back into the object with a 180. Probably wont happen but your not far enough away to turn it around anyway.

I did a jump with a friend, where there was a 10-15' ledge 70' below the exit point. He went SL and I did a rollover. We both easily cleared the ledge. However, I do think it was a rather stupid jump.

I wouldn't do a jump that low over solid ground, but everyone chooses their own level of risk, and I am certainly in no position to judge. One more thing to consider is whether there is anything on the ledge to snag. If not you could prob brush it with some nylon and be no worse for wear.

Saw my buddy today launch very hard twice on
two static line jumps and video clearly showed
him ass to earth at line stretch from pendulum.

Check out these measuresment for the standing
broad jump to get a range of possible distances:
http://www.topendsports.com/...g/tests/longjump.htm

What is your lowest jump to date sir?

edited to make url a hyperlink

to date two differnt 180' jumps. both had full flight/flare. glide ratio is 1:1 on last nights jump.

180 feet is my lowest also so far...

Hmm, do you happen to have a spare
dirtbike you can use to get some extra
seperation and air speed?

Screw the dirty bike, grab some
Planks and straight line that shit:)

when getting that low, you really don't want to push hard on exit.

this is textbook 145'. https://vimeo.com/...57186/video/31125254

i love low SLs, but you def have to be cautious.

To add to the folks who are saying that on a low jump you really don't want to push off, I'll point out that part of the reason is that it makes no real difference. To a pretty good approximation, you can treat your pilot chute as an anchor. So if you're doing a SL jump, with your PC not leaving the object before line stretch, you want to think of the "pendulum" being very nearly attached to the object, or at least no further than your canopy can get from it before line stretch (ie, less than bridle length and probably less than half of that).

So there you are, way out in front of your canopy, with your canopy 5-10 feet from the object. First thing that's going to happen is that you'll swing back toward the object on a 20 foot line (your canopy lines). This is suboptimal.

That's only completely true if you either keep the static line attachment connected after line stretch (which is more or less impossible) or your canopy experiences immediate and complete inflation (also more or less impossible).

The top of that 20 foot pendulum swing will move outward along with your push off as the canopy begins to expand.

I do think there is a certain amount of backward pendulum, but I also think it's not as black and white as people often make it out to be.

+1. Also don't forget that your canopy will be trying to fly forwards as it Pressurizes. So your canopy is trying to fly over your head as much as your body is trying to swing back beneath the canopy. While I do think that you will pendulum backwards it is no where near as bad as people believe. The biggest reason I see for not launching excessively hard is that you aren't going to get very far from the object anyways.

Ha!
so my lowest over ground is around 105ft. but this was from a span. to have a 180, jumping onto a headwind would be disasterous. I was jumping into a headwind, and didnt have a 180. With a building jump as low as you state, if you know that you can easily clear the protrusion with launching then its good IMHO. in a no wind situ. That was the go/no on a jump from the NewOrleans WTC. if i cant leap it then its a no. I then exited on an inside corner that i knew i could clear the ledge. then was faced with an inside >90deg jump. Tom A. and another well known jumper, jumped it some years later but i dont know from where. above the ledge or on the ledge .
So anyway, back to the point. If you think that you can easily leap it without a parachute, you can do it with one (with no wind.). thats my take on it. but maybe my Guardian angel is better than yours.
Take care,
space

Pretty sweet object. Someone had a 90 right on that? or are my eyes playing tricks on me?

I'm not grasping the posts stating not to launch hard. My take on a hard launch is object separation, which is what you are looking for to clear this ledge. Also, with a hard launch your canopy is coming out and beginning to inflate giving you a higher AGL at full inflation. Since this is a DBS, slider down/off jump, static, PCA, or direct bag deployment your surge forward will be decreased by you deep brakes. Plus the canopy will also be flying forward & when you release the toggles & if you keep flight in very deep brakes you should continue to minimize surge.

nope, we were jumping different directions.


oh, i see what you mean now... i think Taylor did have a right off-heading of some degree... i also recall him being packed in shallow brakes, which explains his violent canopy surge/inflation.

I will say this:
130' and 180' is a HUGE difference.
Remember how low your canopy opened on that 250' PCA?

Here are some pictures from 125' B. Stood up. FoxXs265


Strong Push.


1 second after:


From inside:

nice.

I agree, and have watched that video a few times and still think there was a funky downdraft/turbulance coming over that hill going on there.

Come on down and see what we got first hand.

Ask yourself why you want to do this object. Are really that horny for a BASE jump. If so, there have to be better jumps nearby. I've done this for a long time and we have a saying, there are bold BASE jumpers, there are old BASE jumpers, there are no old Bold BASE jumpers.
cliffleaper
38

And I suppose that is why I have not attempted this one yet. I have watched and looked at this one for easily over 6 months.
At this time, I think I am at least waiting till I can try this same height over water a few times and see what the video looks like for canopy inflation/flare response.

Good plan. Water is a lot more forgiving of a partial opening than ground.