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I had some circumstances of my own fault today, that fortunately, turned out much better than they could have.

At "the" bridge. First jump in several weeks, first jump on this canopy in 4 months. 2.5 second slider up delay (on a dagger loaded at 0.69-ish). Snively opening, left >90-off heading, with continued momentum into the turn, kind of diving at the river. Gave left toggle input to continue the turn to a full 360, and planned to land into the wind (to the east) on the beach. Passing perpendicular to the beach in my turn, realized how low I was, and that I'd land in a turn if I continued to final. Made snap decision to stop turning, let the canopy fly straight, keep it square and over my head, and hopefully regain some flare authority. Landed right under the edge of the trees on the beach into a pile of big dead sticks which broke my fall. A few of my lines got caught in the overhanging branches which probably also absorbed some energy. Aggressive flare. Overall, surprisingly soft landing, no injuries. I landed 10 feet to the right of a boulder that I couldn't see before.

Given that it was going to be a slider-up jump, I coulda done the following to be safer:
- made riser inputs during opening sequence to keep on a better heading
- flown the canopy into the water rather than try to keep going for a dry landing. This decision would probably have had to be made on downwind leg, because by the time I had turned onto base I might have been to low and close to the shore with too much energy to avoid getting over dry land. I don't know, I might have stalled onto the shore instead, it woulda been close. I should have just flown downwind into the water, but with the canopy basically in a constant state of turn from opening until just before flare, my situational awareness wasn't fast enough to register how low I really was and what my best "out" actually was.

Other things that would have helped:
- not going noncurrent on this canopy
- being slider down, duh. but slider up is reasonable at the bridge
- not being markedly sleep deprived
- re-tuning my brakes; I've lost probably 10 lbs since the brake setting was last tuned. i've noted this to cause finicky inflation characteristics, and the brakes were probably set a little too deep even at my prior weight, to be frank.

Things that helped:
- flaring aggressively
- choosing to land with a square parachute over my head, into trees, instead of in a turn, facing the wind. (I chose the 2nd worse choice instead of the most worst choice)
- by sheer dumb luck, did not land on that big boulder.
- appropriate footwear/shinguards
- having a good "feel" how much flare power I have left after completing low turns on this canopy (not much). Even if I squeaked the turn to final out in time, I'd have no flare authority and pounded in hard.

I watched a guy do almost exactly what I did, in almost exactly the same place, last fall. He tried to complete the turn to final and landed hard in a turn and his knee plowed into his face. He was literally stunned (awake, unresponsive) for about 30 seconds) when I got to him, and then had obvious concussion symptoms ending his jumping week.

Takeaways: Got complacent. Got lucky. stay current. Get enough sleep/rest. "Even if you're going to land on a cop, don't forget to flare." Go to your outs, early. you don't know how fast things can get shitty, until they've gotten shitty on you fast.
I shouldn't be focused on how great it is that I got away with this, instead I should be more careful and concerned because I almost didn't get away with this.

Some say, "I'd rather be lucky than good," hopefully this helps someone else be more gooder than I was, because I was pretty lucky this time.

I realize that there have been many slider up jumps done at "The Bridge ", but it is a 486' object, can you educate me as to the logic that considers this "reasonable "

Always willing to learn, thanks.

Regards, B.

why did you decide to jump SU? you said 4 weeks since last jump. a slider up jump? if yes where and how(slick, track, ws)? or you just decided to jump this one SU?
i am just curious what made you do this jump this way.

noBASE# xxx

StealthyB: I consider the bridge a great place to do slider up jumps, provided one is willing to land in the water and not fixate on reaching the dry LZ, if they get low.

Some possible reasons for doing slider up here:
1. Much gentler on one's spine & body, especially if you plan on doing a lot of jumps in a short amount of time.
2. reasonably safe place to practice rigging and staying current or getting recurrent in that configuration.
3. can help with vertical separation if you are doing big ways
4. gear testing
5. you want to keep the control lines passing through the guide rings for whatever reason.
6. for sake of variety
7. you happen to be packed slider up and are too fucking lazy to reconfigure your slider.
8. lineover prevention, in the absence of tailgate or tape

yil7: Why I decided to go slider up this time, relate mostly to reasons #1, #2, but also #6, and #7. Not all the reasons out there are good ones. I definitely did some rationalization. Last jump: a high alpine slider-down jump. last slider up jump was like 10 months ago! (slick)

I think the learning point in my experience is not that one should never jump slider up at the bridge because that is clearly not the case. The point is, one should not do a jump that would open them up low (for whatever reason: slider is up, delay is long, etc) unless they have a safe jump plan for it and are capable and willing to stick to that plan. And, target fixation is a cognitive error that can make one incapable/unwilling to adhere to the jump plan. I recognized my target fixation before it was too late, but even sooner would have been much safer.

I also could have done a slider down jump first, as a warm up. But that is no guarantee, I would not have a similar problem on my next jump...

if it's #7 you've already asked my question
and please don't misunderstand me, I am just trying to understand not to judge you.
it was a good lesson for you thats how I see it.
cheers that nothing happened worse!
cya

Thanks! It is easy to rationalize & get complacent with this or the many other little ways we like to get lazy, I hope my warning makes me or someone else think twice next time.

I have zero slider up BASE experience, but I've heard that short delays (sub 3sec) slider up are an invitation heading problems (which can also hurt your back)

Is this something you've heard of experienced firsthand?

Where'd you learn this?

+1

I probably have more subterminal slider up jumps than any other type of jump, and a local object where ive seen a ton of 3ish second slider up delays. Off heading are probably a bit more common than on slider down, but not by much. You can also steer a canopy while is sniveling. On an appropriate object (not an underhung cliff) subterminal S/U is nothing to be afraid of.

Just like hjumper33 I probably have more subterminal slider up jumps than any other category of jump that I have done, but they have always been in the 3sec + range and usually on objects of 600' or more.
Not to argue, but for the sake of educating less experienced/ newer BASE jumpers I find your logic extremely faulty and dangerous.
So answer me one and only one question.

What is the minimum low exit altitude for a safe slider up jump?
Perhaps hjumper33 can chime in on this also.

Regards, B.

Hey, no worries. I don't think the answer to your question is a number, because all objects, gear and personal tolerances are different. I think the lowest exit altitude, slider up, is the one you expect walk away from the landing every single time, at that specific object. Same criteria for slider down. I would never do 486' SU from anything I could strike, or didn't have a generous water landing option. I understand if that is not your style of jumping and makes you feel uncomfortable, but we all have our own risk tolerances and I know people who consider any slider down cliff to be "dangerous and faulty" logic to jump, and I would disagree with that too, but it's their right to feel that way.

If you want to fixate on the hazards of doing <3 sec slider up jumps, that's fine and everybody will take something different from my story. But I think (and maybe so do others who jump SU at the bridge) that should not eclipse the other relevant learning points from this experience, because there are several.

I have 2 questions for you:
What is it exactly that you find dangerous: is it the low deployment airspeed of a <3 sec delay, regardless of height? Or is it the height itself that's the problem?
I listed several reasons one might want to jump SU at this bridge. You categorically called them "faulty and dangerous." Obviously the "lazy" reason is a bad one, and also somewhat tongue-in-cheek. But perhaps you could clarify for me which others you found faulty, and exactly why? I am genuinely interested in learning new perspectives.

Thanks!

How 'bout an offheading into a solid object? Or getting an offheading and correcting it by flying yourself into the ground? Just sayin' i've heard short delays on SU sacrifices heading performance. Poor heading performance on a solid object could mean a strike. That could also hurt your back. Obviously the bridge isn't something you can hit.

Sorry, one more question. Since you mentioned doing many 3 sec slider up, at a 600+ foot object, I wanted to ask, are these solid objects?

Personally, at my skill level, I would not feel comfortable taking a 3-4 second slider up delay off a cliff. I would do a 600-700' cliff slider down, and do up to 3.5 seconds. But others may feel differently, I would just not follow them. (But I would take video!!)

I like this thread, it potentially brings up many points and I am not engaging in it to argue and fight.
Once more, I will ask you, what is the lowest altitude to safely deploy and land a canopy in a slider up configuration?
Can you give me an answer in your best estimate to that question?
There are many jumps that are safer over water than over a solid landing area, but at certain speeds of impact water isn't a safety buffer as many people have learned to their dismay, most notably at the potato bridge.
Ask yourself why slider off is considered a better option on short delays and low altitudes? Why push it?
I think your point # 3 is ludicrous, I read it as saying that impacting with nothing out is an example of good separation LOL!
OK , so I'm exaggerating, but will pay more attention to this post when I am not sitting in an Irish pub in Norway with some Norwegian plying me wth shots of Acqauvit,
Cheers, B.

PS, can anyone answer my question, since this thread has brought it up, What is the lowest safe altitude to safely deploy a BASE canopy in a slider up configuration? Opinions please, and I will tell you the lowest I have seen it done, and it was fucking terrifying!

This thread is discussing SU off-headings off a bridge, not a solid object. Obviously short SU delays are higher risk, but there's nothing wrong with going SU at the Perrine if you've got an injured back or neck.

Really???

Thank you, that is the point of my questions, what do you base this logic on? Is it because it is something that has been done in the past and people have gotten away with it and is thus acceptable? Or is it based on knowledge of safety margins in the slider up configuration?
I am still curious as to the generally accepted minimum opening altitudes in the slider up configuration and so far nobody in this thread has offered any insights to this question.

Regards, B.

My experience with my OSP has been that going slider up on a short delay at a bridge results in opening 50-150ft lower than slider off.

Really I think its closer to 50-75ft lower with the slider, but accounting for increased variability, I think an extra 150ft is a reasonable number for planning puposes. At the perrine bridge that easily fits within my personal margin.

Based on the height of an object you have a certain amount of altitude to play with until you need to have a canopy. You can do a go and throw, or you can take a 3 second delay, or you can slow your opening with a slider. All are valid uses of altitude as long as it's properly planned.

I have gotten away with it and now I find it acceptable. I decided it was safe to do because the water would break my fall with a partially opened canopy and the landing area is huge. I wouldn't jump the perrine slider up in strong winds or cold weather.

I agree, it is a great discussion! I do not take it as being argumentative at all.


I will try to give a better answer than my last one, but my general answer is the same. If you are asking for an exact number, I do not think it exists. It is the same as asking the lowest possible slider down jump height. Whatever is lowest for one person, someone else will go lower. Having jumped from the bridge slider up many times, I would feel comfortable trying a slider up jump from 425-450' over water. I would progress my way down slowly, if I had any reason to. From an Antenna with an easy LZ, I think 650' with perfect winds and 3 sec delay is the lowest I would go SU. From a cliff or building, I don't have much experience in this height, so my opinion is worthless (not that it is worth much in other things, either).

What is the lowest height you would jump SU from, off a bridge over water?

Short of changing the physical environment itself, here is what would change my mind about SU jumping at the bridge:
- seeing lots of people suddenly getting hurt doing this
- a knowledgeable person explaining risks that I did not understand before
- having a bad experience / malfunction, where being slider up was the primary cause (i.e. not this case. I put the blame on target fixation with slider up being a secondary cause, but this could have happened on a deep SD jump too) I am talking like, tension knots below the slider that flew me into terrain or severe line twists


Haha no that is not exactly what I meant. I have watched several of the record-setting big-way jumps off the Perrine. When planning for jumping 10, 15, or 20+ jumpers off the bridge at once, it is very important to stage everybody's opening, and you must use every bit of space to the best advantage, to avoid canopy collisions. Interspersing some jumpers with slider up deployments helps fit more people on the load. You can also put someone on a round and do 4 sec delays into the water, I would not do it's definitely been done. Obviously this is a high-risk activity and a very rare event, but it is a real reason I have seen people go slider up, so I mentioned it.

Me neither. absolutely not. (Although my idea of "cold weather" is a little abnormal)

Haha, perhaps this is my favorite response and explains you crazy fucks the way I see you (platypii and Colm ).
No one has given me an absolute figure on how low you can deploy slider up safely because none of you dickheads really know what you are doing?

Bottom line is that you are pushing the envelope and don't even get it!!

Well, that's BASEjumpers for you!

Best of luck,
Regards, B.

Ok, well, sorry I was a "dickhead" by trying to answer your question in good faith. Did you see my other reply?

Please educate me, what is your answer to your own question? 699 feet? 700 feet? 701 feet? Does it change based on object type or LZ?

I will not call you a crazy fuck, but I think it's backwards that you would not jump the Perrine bridge slider up, but a 3 second slider up delay from a 700' cliff is safer in your book.

Look I think this is a good discussion, lets keep it going and not name-call here please. I have explained my logic, now I would like to hear yours.

Sounds like his shots of Aqauvit caught up to him :-)

Haha if he has any manners, he will share some of it!

The reason no one has given you an "absolute figure" is because no such number exists, just like it doesn't exist for the question "What is the lowest you can safely deploy slider down?"

Everyone will have their own answer, based on gear, experience, evaluation of the object, and their personal risk tolerance.

I gave you a pretty specific answer of how much lower I open when slider up, measured in feet, including taking into account the increased standard deviation. That way I can evaluate a jump based on object height and planned delay. Not sure how that leads you to the conclusion that I'm a dickhead that doesn't know what I'm doing, but ok. Please educate.

Absolutely, :-)

But I still don't think my question was ever answered,....
What is the lowest exit altitude for a safe slider up opening? and this is meant in the context of Colm's original post with a sub three second delay.
Also no disrespect meant to Colm as he usually shows good knowledge and good sense in his posts, although personally I don't feel any of the seven points he made for this jump really justify jumping slider up on low objects.

Regards, B.

My inebriated sarcasm was triggered by posts such as this, and ... no, Colm I don't actually think you are a "dickhead "

Let's not forget that your original post was labeled "Near miss " although you pointed out it was in regard to your landing decision.

What is to be gained by jumping slider up at the Perrine is still beyond me since a snively opening could put you impacting the water at an undesirable speed. And since there are people that glean much of their knowledge of BASE from these forums I appreciate your original post warning people that it was bad judgement in the first case,

Regards,B.

I have done slider-UP at the Perrine a few times.
I have done slider-UP from antennas at 600 feet.
My own thinking on the topic is this:

0 to 3.5 seconds Slider-OFF
5 to 9 seconds Slider-UP
10+ seconds Terminal

4 second slider-UP jumps should be from objects
you can not hit and where heading performance
is not critical, examples: Perrine, NRGB, Crane.

I agree with your sentiment, that slider-UP with
minimal delay is not ideal, but I think it is still
much safer than doing 3 or 4 flips in Idaho.

Thanks very, very much to everyone who has replied with opinions or questions!

So far, there have been a variety of opinions on slider up at the Perrine. Some say it is fine under the right circumstances, some say it is significantly more risky but not the riskiest act people do there, and at least one person says it is an unacceptable risk. Is that a fair generalization? I think this is a great discussion.


Thank you for clarifying your opposition with this sentence, I hadn't really understood your reasoning so far, and that was getting frustrating. As I wrote above, an experienced person explaining risks I did not understand before, would make me reconsider, so I am. I think a little snivel is to be expected < 3 sec as probably happened to me, but I hadn't considered it likely that a snivel would be so severe, to put me in the water at more than 80km/sec (5mph / equivalent to a 25 meter freefall). Maybe I have underestimated that risk.

My prevention for snivels is to fold (not roll) the nose of the outer cells outward, fully expose the center cell, and not use direct slider control (I always use indirect). And, certainly, take an appropriately long delay. Can other causes of snivels be identified, and how can they be prevented? Are they like tension knots, i.e. we know certain causes but sometimes they just happen? What's the longest snivel you've seen? Please help me understand it better. And others are invited to answer too.

Also B- Maybe if you can clarify your question, about "minimum height for SU," I can try a better answer at it, but right now what you are asking is simply too ambiguous. If you asked something like, "minimum height from [a certain deployment airspeed] to get a [large/small] mesh SU canopy inflated and flying, with no additional padding" that is more answerable, but that is not what you asked so far.

Lastly, B- I had several other questions for you up above, I am very curious for your opinion, if you have the time to take a look at those too I'd be grateful.

Thanks again,
Colm

And also over deep, calm water (as was the case for Colm)?

I've seen someone PCA a 180' bridge slider up over deep water. I'd call that more of a stunt than a jump. The canopy was packed with no slider control (neither direct nor indirect). The jumper had a full canopy and impacted the water (with the brakes still set) just as the slider reached the links. There was no injury.

I've also seen multiple jumpers with no parachute impact water from 65 feet without injury (repeatedly, in various stages of inebriation).

My observation of those jumps leads me to think (without any further testing) that over deep water you can probably PCA from any altitude. There may be a convergence point where you are too high to survive without a parachute, but the parachute hasn't achieved sufficient inflation to reduce your fall rate to a survivable speed, but I'm not convinced it's not the other way around.

I think this is a case where most people have an opinion based on generalizing from their similar experiences, but no one has actually done any real testing to formulate a more solid evidence based conclusion.

challenge accepted.

i'm pretty tapped out for the rest of 2017, but this would be a fun project to research next year when the temps warm up again. anyone want to help? it would need side and overhead video, and some lasers. i'll be the first guinea pig.

Sounds great if the parachute inflates as expected. But, to play devil's advocate, what is your take on StealthyB's concern, that an unpredictable long snivel malfunction would insufficiently slow you down, to the point where you impact the water injuriously?

edit: formatting

Any unpredictable malfunction will likely cause injury on any BASE jump.

In this case I was talking about a theoretical minimum exit altitude over water, rather than a real-world jump with a built in margin for error/malfunction.

To be fair, though, there have been many real cases of impact in deep water under a canopy with a partially descended slider that did not result in injuries. And there have also been many real cases of impact in deep water under malfunctions that resulted in zero injury.

Which means that in discussion of malfunction scenarios with impact into deep water the operative question is going to be "what kind of malfunction"? Which leads us to start inquiring about the relative descent rates of various malfunction modes--which is going to be another huge rabbit hole full of conjecture and with very little real world evidence.

Your original post reminded me that when people first started considering the Perrine to be an acceptable slider up jump, my immediate thought was "Why? " or more specifically "Why bother adding more risk " to what is essentially a very safe slider off object.
For instance people exiting wearing a Wingsuit begs the question "Why? " Is it done so that they can claim a bridge WS BASE jump? they are certainly not flying the suit...but it gets done.

So my original question was, "What is the lowest altitude to safely deploy and land a canopy in a slider up configuration?

As Platypii correctly pointed out there is no hard and fast number because there are too many variables, but one thing is for certain,.... you can't take a 6 sec delay off a 486' object whether it's over land or water and expect to survive, if you get my point.
In other words, as I have always taught people about BASEjumping, the very first thing that you have to respect is the height of your object and the limitations that it presents.

Tom, gives the example of a 180', PCA'd slider up jump, with an intentional water landing, sounds like a reasonable enough "stunt. "

When my old friend Bob Neely BFL#43 and I first got our two canopy, Sorcerer rigs he initially packed the reserve in his rig, slider up, (for unknown reasons ), and then went to demonstrate a cutaway from about 200' ( as measured by the guidewires on the antenna ), his eyes were popping out of their sockets when he had less than a 3 sec canopy ride. Bob later went in at line stretch in a swamp from an 800' antenna exit, guess he could have used a little more water under him.

Anyway, as you know, Rule of thumb has always been, sub 3 secs, slider down, anything more, slider up, but if you are taking 4 sec delays before opening at the Perrine (I know, you see it all the time... ) then you are getting down and dirty and 5 secs doesn't leave you a lot.
Of course there are more dangerous jumps being done at the Perrine than short slider up delays.
The 3 to 6 sec range slider up I think is a category in itself, and since you are not going to take 6 sec delays at the Perrine, and unless you are planning to land in the water, a 5 sec delay doesn't give you much room for canopy control, you seem to be limiting yourself to 4 secs, so why bother?

And the answer to my original question reminds me of the old skydiving question of " how low can you go ", Well, "The guy with the answer is lying under that tombstone over there..."

Regards, B.

 

I agree, this is a tricky subject, and an interesting and important discussion to have. I think the real answer is kind of dependent on the object. 486 ft on a bridge is in the "acceptable but has potential to get hairy quickly" category. But ill blather endlessly expanding on that answer below.

Having a local object that I became very comfortable with 2-3 second slider up delays, ive found it to be a useful tool. I have an odd array of lowish slider up jumps including a couple of 500ish foot smoke stacks, probably 8 slider up buildings in the 500-900 ft range, a couple of cliffs in moab, australia, ect.

If I feel I can take the same delay I would be comfortable taking slider down, and still have sufficient altitude to land safely. Ill consider jumping slider up. If I can take a three slider up, or a three slider down, preference to the up.

I also assess the likelyhood of an offheading screwing me. In my person experience, im maybe just slightly more likely to have a 180 slider up, but much much more likely to have 15-45 degree off headings. I quit freefalling guy wired antennas a long time ago, and I think jumping low ones slider up is completely silly. Ive only jumped a 500-800ft cliffs slider up, and only when I knew I could sprint my ass off on the exit. Buildings from corners, and with surprisingly good LZs.

I dont find the Perrine to be a particularly appealing slider up jump personally, though ive done it 2-3 times. I think if people want to learn how their canopy responds in a 2 second slider up delay situation, I think its as good as any place I can think to learn it, but youd better be prepared to go into the river. I dont think the critical error was necessarily packing slider up on this jump, but the others the OP already identified, mainly not landing in the water. We all know you dry faster than you heal, but there have been many injures due to wanting to stay dry.

Slider up subterminal is definitely not a beginner technique to take to technical objects, but it is a nice tool to know how to use. I put it in the same category as being comfortable doing low static lines. Not everyone will do it, but they can be done if done properly.

Also to your original question. In my dumbest base moment of all time, when I had about 200 jumps, I got PCA'd off a low highway overpass in a rainy northwestern town from 150ft (47m) slider up, rolled nose, on an ACE. Flared with about 5 cells, fell onto my face in the rain onto a gravel parkinglot and scraped up my bare hands, but no other injuries. Guy who PCAd me though he killed me. Long rambling blaming of multiple factors which basically come down to stupidity and complacency.

If I had to give numbers, which are based only on my personal experience and comfort level, assuming perfect conditions, fast sprinting exits on the cliffs, and open LZs, if I was jumping an object for the first time and was considering slider up, B - 600+ A- 1300+ S - 500+ E - 600+.

Finallly, some sense. Anything under 600ft slider up is asking for all sorts of problems. Throw in a hesi and your fucked otheriwise. Ive heard firsthand accounts of what happens when people impact water at line stretch and if your insides hanging out is a goal of yours then make sure you share the footage if it eventuates so we can all learn from it.

Interesting to note, how it seems to be Americans who live in the USA are taking this opinion, and people who live overseas or are not American (if user profiles are any indication) seem to be more concerned by the fact it was slider up alone.

It's of course a small sample size, but is that a jumping style difference? Or people who jump the bridge more often are more comfortable there? Or reflect the type of jumps we all normally do? I don't know.

Don't make assumptions Colm!
if you are taking this personally and referring to my responses to your posts?
Don't judge by user profiles.... you would be way off the mark,
How about jumpers that have been jumping the Perrine before you were born ( well at least before you ever laid eyes on a parachute ) and certainly before Tom Aiello made his first jump from that particular object. Guaranteed,
And for what it's worth before hjumper33 or anyone else posting on this forum ever jumped that fucking bridge, or even knew it existed.
But, since Tom has dedicated his life to Twin Falls and the Perrine I acknowledge that he knows more about that object and that style of BASE jumping than I do or ever will. ! OK, maybe you are older than I think, sorry, but don't assume that because someone posts from a foreign locale that they are not more familiar with your local object than you are. I can assure you that I am, I jumped it before Tom, or any of the other so called locals even considered BASEjumping.
So don't try to defend yourself from my opinions of your technique at the Perrine because you live in SLC and it's your closest, favorite, object.
I know it as well or better than you do, but that said, best wishes, regards B.

Please allow me to clarify, sorry if it came across the wrong way. I meant that, "among the small handful of people replying to this thread," I merely noticed that people with US flags next to their avatar tended to have slightly different take on SU jumping at the bridge, compared to people with European (or other) flags next to their avatar. If you are inferring a judgement about familiarity & experience with an object, that is not at all what I was thinking, nor do I think that'd be an defensible statement to make at all. If you were inferring complacency with regard to an object, I'd be more apt to agree with that, but it's not exactly what I meant either... is that fair?

The point of my question was to wonder if geography and culture had an influence on opinions posted here, that is all, and I think that's 100% a worthwhile question.

Though you have been very engaged in this discussion and I really value hearing your opinion because it is different than many of those I "grew up with" in BASE-- I am not trying to make any sideways references to your replies. There have also been several other country posters here (including one whose post appears to have been deleted as quickly as it went up, I just happened to see it) who are critical of my choice to jump SU and I don't at all begrudge anyone that. And I know that your or whoever's avatar flag likely or not has nothing to do with where you've actually spent most of your time jumping... so that's why I asked the question.

So beat me up for jumping SU if you think it's a bad idea, but I wouldn't have hoped for you or anyone else to take my last post as a criticism or judgement upon anyone.

The interesting thing about this whole thread is that it addressed a very significant subject, Slider up limitations.
How much consideration do we give to this, and what exactly are the accepted and fixed criteria that we abide by?

Thanks for your input, B.

That is an awesome question and I hope it prompts everybody to think about their own personal limits too. I always try to re-evaluate mine, and this thread will certainly help me do that, particularly your input.

TomA's point above, that there is a lack of data, applies to a whole lot more BASE than just this topic, but ya gotta start somewhere. I feel like I owe it to myself to do some better actual measurements, more than just "oh my gut experience makes me think such-and-such." or "gee, it takes about 100-ish feet plus or minus (for whatever)"

So if anyone wants to help on a science project and is willing to spend some time at the bridge, please PM. we will do some fucking science, bitches.

https://m.youtube.com/watch?v=d6lYeTWdYLw

You do not need a slider for that. It's still a bit of a shitstorm discussion, but line release mod is more trouble than it's worth, at least in my book(wasn't always though)

+1

I have done a fair number (meaning not that large) number of 3 second delay slider up jumps at twin over the last 20 years, usually at the end of a trip when my 57 year old back (or younger years ago) is hurting. I have always landed on land but the water is a real possibility if you have a severe off heading or any line twist. You simply have to turn to land immediately. I always did it when it was warm (it would obviously be stupid in winter) and when there was a boat to pick me up if I landed in the water. I think there was usually a beach also. I felt it was pretty safe but I suppose I could be mistaken:)

how about 4s slider up?
did you do any?
same place

You are absolutely correct, you don't need to. Good correction. Personally, I just keep my rigging simple and LMR = slider down, guide rings = slider up and I plan my jumps appropriately.

-
This also same .. It is safe . About half the jumps I done there are slider-up . You get a line-twist or two once in a while and off headings but never had a problem ever staying dry . You get plenty of flytime doing slider-up jumps in Twin, It's fucking Bridge with a football field for LZ and a nice big beach when the water is low, Holly Crap,I really don't get this Thread Topic ?
Plus..Slider-up jumps at Twin are so nice and smooth like butter, easy on the Back also .

.

i'm with Ray on this.

but maybe i'm just getting older and grumpier too. of course it seems now most of the people are working harder on fitting in with the cool guy homeless camp that hangs around the visitor center smoking weed and drinking beers all day, cursing at the locals and tourists... instead of actually trying to be good at something.

whatever. because i was bored and am not a good base jumper, i thought i'd just post this video of my very first jump there ever. enjoy. or don't.

https://vimeo.com/234009396

thank you for sharing
nice jump

That a good example . You got an AssLoad of flytime on that jump in the Vid.
Also .. those Slider-up TARDS with dragging down the Canopy for a delay are real smooth easy on the Back . You can get hooked on doing those pretty quick .
.

I appreciate the additional replies, guys.

What about thoughts from other people visiting the bridge from overseas: how comfortable would you feel / not feel, doing a slider up jump? Different crews and different cultures might have different comfort zones or different concerns. Have already heard from a few travelers, I'm curious to hear more.