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My buddy and I are considering getting a 43 meter (141.076115485559 feet) lift from a company next to our DZ. A skydiver friend of ours knows someone from the company and we would not have to pay for the time on the lift only per day... We are considering whether to PCA or DB the object... we dont have a direct bag but if it was really worth waiting and doing direct bag then we would do that. We also considered finding a smaller bridge over water or a lake or something we could just take the lift up and over... The good thing is since we would have the "object" then we would have unlimited time for preparation with the basket on the ground. It is a box about 6 feet by 3 feet and you can tilt the upper boom so you have about a 10 foot overhang. any suggestions? It is pretty low but the pro is that we have unlimited prep time and their is no climbing involved...

If only it was .000000000000000001 ft higher

nice one.... :)

PCA should be fine. If you want to learn the art of Direct Bag, you have the ideal place to do that, since you can do all the rigging very easily. But for "just get a jump in" I think the PCA is going to be fine.

What about a TARD?

sure... but not as desireable as the pca or direct bag... just not the same. Definately want to do one or both... :)

not the same, but LESS rigging. what is the landing area like?

You have to ask yourselves if 43 m is a good enough reason for maybe risk limping rest of your life! Repeting jumps so low will increase the possebillity for a incident.

I have two bursted disc in my back that make me walk like an old man! I wish i treated my back better in my young days! Many of my friends are limping around after complicated ancle incidents, and I sure they are thinking the same as me!

Enjoy and good luck.

Happy new year :-)

 

Good ankle protection is required for this kind of jumps, and NO wind condition..
I have never tried Direct Bag so i won`t comment on that..but i have bunches of PCA`s and SL`s and this jumps is quite reliable in heading performance..
I think you could deal with a 90 off heading, but more than that you could be in trouble..
Sound like a cool boogie
stay safe!

landing area is our choosing... we have a 1.2 kilometer by 600 meter field or a lake.

what's jour experience in base sport? how many low jump do you have? have you got body harmor, helmet, knee protection,ecc.ecc.?dont' have hurry to brake yourself!
bee quite!

helmet, knee, elbow, ankle, and medical. I am very inexperienced and am only assisting and learning with everything my buddy is doing. He is fairly experienced with many jumps in the swiis valley, however little experience with low jumping... hence the reason for trying to get as much info as possible. The jumps will not be attempted if both of us are not totally convinced on whether the majority of the risk can be managed efficiently... :)

I'd recommend getting a bit more experience with the low stuff before jumping 140 feet. If everything goes well, it will be a short ride but you'll definitely think it was easier than you expected. If anything goes wrong, it will be an even shorter ride, with a high probability of broken ankles etc. If you have not already done so, do a few jumps from 200 feet, and a few more from 170 feet before moving to 140 feet.

Also, are you sure you'll be jumping 140 feet even? With the crane over hard ground, I'd be tempted to put the boom out at a slight angle to improve my chances in an off-heading, and so the vehicle isn't directly under me in the event of something like a tailgate hangup. A 15 degree angle will knock off 5 feet of altitude, but will give you 36 feet of clearance from the vehicle.

Although 5 feet may not seem like a big percent of your total altitude, you can't use your total altitude. It's been my experience that it takes about 120 feet to get a flying canopy over your head. You can go lower than that, but your canopy won't be flying properly. Taking 5 feet from 140, you are actually eliminating 25% of your usable altitude, i.e. the difference between where you are and your basement.

Finally, I wouldn't do this kind of jump without a laser rangefinder in hand. Even if the guy says the boom is all the way out, and that's supposed to be 140 feet, at this altitude small errors make a big difference.

Michael

Hi,

We've run a couple of crane boogies from 100m cranes here in the UK and personally I've jumped from a cage the same height as you're proposing. There's more than meets the eye but it's very doable and great fun.
From 43m SL or PCA works fine, but it's quick from that height, all over in 5 secs from start to finish. Use a 46"+ PC. Vented canopies are the best bet but it's fine with nonvented. My ACE260 was inflated and flying before I flared.
Having a well thought out SL attachment point and some consideration of SL principles helps a great deal. Also ensure that your PC & bridle is set up so that neither get snagged on exit.
You need a suitable cage to carry the jumpers, preferably with an open side or door. Bungee jump platforms are a good design. You also need an orientation bar to set the cage to be facing out, down wind if there is any. Again, Bungee jumpers know all about this. You also need a bit of overhang, we use about 5-10% tilt. In addition you need a "cage monkey", an extra non jumping person to coordinate with the crane operator (radios are ideal but hand signals work, except when he's having a sandwich and not looking out for you waving at him) for lifting and also to disconnect th O-bar before controlling the descent.
You need to have the cage monkey harnessed & connected to the cage at all times and all jumpers connected during lift, usually by a sling and karabiner to the chest strap. It's not unknown for crane cables to snag and "birds nest", and if this malfunction releases suddenly everyone can get thrown out of the cage.
You can't launch! Any power during exit just gets transferred back to the cage giving the jumper a sketchy exit and it makes the cage rock around. You just drop off, head up.
Wind conditions are not a worry, just point the cage down wind of the crane and go with the downwind landing. You won't have time to correct heading. Full on 180's mean you just have to sink it straight down and PLF without releasing the brakes. If the winds pick up the crane operator will probably call it before you do for operating reasons. Cranes work on a very tight region of balance, the more so the higher they lift and there are loads of buzzers in the cab of modern cranes that go off if it is even in the faintest danger of tipping. Make sure the crane operator knows what you're doing and how. They're not fond of surprises.
Make sure you have a nice forgiving landing area, grassy meadow good, tarmac not so much, crane yard bad.
Have fun, jump yer tits off and.... stay in control. After all you've done 5 easy & fun jumps that morning and looking forward to another 5 before sunset it's very easy to get too over confident and complacent. It may be only 43m but it'll still kill you. Keep an eye on the the safety routines, crane control and everyone's fatigue and confidence levels. If you think everything through and maintain control you'll have a great time. But above all, STAY SAFE!!

If you've any questions the by all means email me at...

max@ukprobase.com

Stay safe.

Max.

consider a site where you can extend the boom out into space?

like at a short cliff...
maybe an abandoned rock quarry?

see if you can gain another 20-30m...

From his first post:
"We also considered finding a smaller bridge over water or a lake or something we could just take the lift up and over... "

Heres avideo of a 138ft (they say) B jumped 4 different ways. Might give you an idea of what to expect...

http://www.basejumper.com/...n/good_time_142.html

B is for bridge, or... building, depending on which acronym you use.

Bridge
Antenna
Skyscraper
Earth

  haha yes sorry...a Span

 i don't think that's OSHA approved how much per day??

If you have vented canopies on the marked, I dont see any good reasons for using non vented for a low jump like this!

Quote "If you have vented canopies on the marked, I dont see any good reasons for using non vented for a low jump like this!"

....because maybe you don't own a vented canopy and can't afford to buy one right now??

Like I said, vented works best but nonvented aso works fine, just like in the old days before we had vents.

Max

And a Old Mojo is still not a choice from 43m! Neither a old Fox cp top skin canopy! There is to many jumpers limping around from the old days, do the new jumpers need to do the same mistakes we did Max? When do I see you in Romsdalen? I think I have some old footage of you on vcr tape from kjerag in your old white wingsuit! Dam you did fly that one! Paul

copy that..the difference between vented vs non-vented comes first when you freefall an object, not with PCA/SL`s..

Why is that? Low speed deployment seems like a low speed deployment...

Not saying you are wrong, but would like you to elaborate.

I have to disagree. Vented canopies are wonderful, I jump nowadays one but saying the are not an option from 43m is a bit harsh. Below is the link for two years old clip about one certain 38m "big" wall, canopies used in that one were good old Mojo with about 400 jumps on it and non vented Troll (about 200 jumps). Wise, maybe not ? Doable (and fun), hell yeah. :) http://www.cs.helsinki.fi/...i/talvimeininkia.wmv

Now we are back to the issue if it works fine for a jump or two! If we had statistic over 1000 jumps, Im sure you would see a huge difference! You can think about it after you have a broken ancle, or comressed spine, if you should have jumped with a vented or not! If you had the best ecuipment, landing area, windcondition etc, you know you did your best to avoid it! Simple isnt?

It is your choice to prepere with the best equipment, I just suggest what I have learned by the years, not telling you what to do!

sorry, im not a qualified rigger so i can`t explain it. It`s only based on my own experience and watching my friends jumps..but if someone here could prove the opposite and explain it i would like to hear it..
The main reason that i have a vented canopy is when you hit the object, you have a better chance to survive when the bottom inlets helps the canopy to keep flying when a non-vented probably would collapse..

I have thought a lot about doing this myself - but with a bit more altitude...

I have had a contract previously to do some recurring/yearly work on the sides a downtown buildings. I pull a permit to close the street overnight and setup a (very large) crane with a basket to lift humans to the worksite. The work we do is only 30 feet off the ground, but to get there we need a 320' boom and jib because the stuff under it prohibits a traditional man lift.

Last time we did it - a few employees wanted a "ride" so we took them to 300 feet by raising the boom to full height before retracting the length on their way "down".

If the gig happens again, I am thinking ending the gig with a jump... I have the crane (rented). I have the permits to close the streets. What else do you need?

Oh, ya... OSHA approval, it is a crane run by a permitted company after all. DAMN....


But - here is the problem, other than OSHA. Our street permit is only for 8 hours, and the setup fee for the crane is so expensive it is like $.25 a SECOND for the setup alone, not including the union crane operator's time or running time on the crane.

Might as well go to a wind tunnel for that price and afterwards go hit an A

I don't like hitting them. Jumping from them is fine.

I know the feeling, I wont hit a violent woman, but could sure as hell choke one...

I agree, we do not have enough statistical data to do any valid conclusions, to any direction. I jumped that same E with vented troll a year after and based on a video there isn't a huge difference there. Of course when talking about 4-5s canopy rides it can be argued if 0.5s is huge, sometimes it could mean the difference between compressed spine and walking away from it.


Yeah, it is everyones choice to use the equipment they feel appropriate for the job. As I previously said, I too suggest strongly to people to use vented canopies and arm themselves with the latest technology in hand. What my point merely was that it can be done (and has been done) with unvented stuff as well. As you said, the jumper chooses on what setup he wants to go...

Most base specific canopies work good enough under perfect conditions, but when you have crosswind from behind and tailwind, your canopy will not pressurize as quick as an vented one!

I think maybe some are missing the point a little so I'll elaborate somewhat....

Yes, vented canopies are the bomb for this kind of stuff but that doesn't mean it can't be done without vents. There are very few black/white situations in BASE, but many many shades of grey. What may be fine in terms of gear setup, winds, altitude, temperature etc on one jump may not be fine on a similar object or even the same object an hour later. The secret lies in the third of the BASE triumvurate - 1)Mindset, 2)skills and 3)knowledge. The better your knowledge and understanding of ALL the variables the better decisions you can make with the right mindset, and the better you can execute the jump with the right skills. It concerns me how many jumpers concentrate on 1 & 2 but are woefully inadequate in 3.
I guess what I'm trying to say is that while I'm not dissing the benefit of vents, if you factor the performance of your gear properly, you can decide if this jump is doable (with your skill set).

Hope that makes sense.

Max

PS Hey Paul, how's things? Long time etc. I've not been in Norge for a couple of years, and I didn't see you last time I was at the Heliboogie. Hope you're well and it's all good. Shout me if you come below the arctic circle, it'd be good to catch up and maybe you can jump a low crane (or something) with us Brits!

I can't believe, after this guy mentioned 2 or 3 times that he had a lake as an optional landing area, no one mentioned that that was definitely a good idea. My blackjack (vented) has been pressurized and flying no more than 60ft below the exit, every time I have static lined or PCA'd it.

I'd say to kick your boom out at an angle far enough so that you can exit the top as far away from land as possible and over deep water. If your static lining or PCAing a vented canopy (or probably any canopy for that matter) into deep water and don't have to worry about the canopy flying you over land before impact, you shouldn't have to worry about anything. People jump from 120ft into water without parachutes.

One thing you might want to take into consideration (Crwper taught me this) if you launch strong on a PCA or SL you might end up swinging back a bit because the canopy is pressurizing slightly behind you. This could cause a painful belly flop.