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Any details on what the reefing method for this jump was? Or what could have contributed to the malfunction?

Low airspeed has been a contributor in every tailgate hangup I've seen.

Has anyone documented a case of a tailgate hangup on a free fall deployment?

Thats what I wonder too! Some people seem to think tailgate on a SU jump is blackdeath, others use it without a problem.

Yes, but with questionable rigging being a factor. Hair tie was used as a tailgate rubber band.

Well, there's your answer, that simple.....
Don't deviate from tried and true procedures!
Regards, B.

Do you think it's possible to have the tailgate hang up purely by using too many wraps of a standard tailgate rubber band?

Just asking as I usually put as many wraps on as I can. Just wondering what else would normally contribute to a tailgate hangup.

Never double stow a bungie that won't break
Never do more than a double stow any bungie, find a bungie that's the same as everyone else uses. That goes for base and sky jumping.
The tailgate is not meant to take a shit load of force it's just to gently hold the control lines in the centre until needed.

Yes.

Who taught you to do that?

Edit:
I have seen tape hang up enough times that I won't use it.

Yes too much wrap or a rubber non adapt for TG... as on this photo on a 70m SD where a friend used un rubber generally used for undirect control of slider under TP... too big rubber = nice horse shoe!
So for static jump, a PCA or a free fall SD it is better to know how to manage its TG.

Out of interest, do you know the average amount of wraps these hang ups used, and is there some correlation to the freefall distance and WL in your opinion?

I use a double wrap of tape on every SD jump, and from reports have had very minimal premature tailgate failure, and no hangups. Just curious as to what others are doing out there?

You do realize that TG rubberbands usually fall off rather than break off, right ?

Why not just superglue your TG lines together, so you never get a line over ?

What's your reasoning for max wraps ?

Yes.

I've seen two cases now where a rubber band that was purely wrapped hung up on a PCA. In one case it was wrapped three times, and in the other case five times.

In general, at this point, I would not recommend wrapping more than twice for a PCA jump.

I have seen many premature releases on tailgates (probably one for every ten or so free fall jumps I have on video).

In the past few years I've also seen an increase in tailgate hangups, I think because people are becoming more aware of the premature releases (and wrapping tighter in response).

Hangups are much rarer than premature releases (I've seen hundreds of premature releases for each hangup) but they are also much more dangerous.

Did the tailgates you observed release? What can you do in an incident like this to help the tailgate release? Would unstowing the toggles and pump the brakes hard help? I'm curious to know peoples thoughts on this? S
hitty situation, glad to hear she is somewhat fine after that experience :)

In those two recent cases, one cleared instantly by popping the toggles, and the other did not.

I have seen several other tailgate hangups cleared by popping toggles, though.

I chose to do it myself after seeing some outside footage of my openings where I had done (I think) 3-4 wraps, and it seemed to have not been enough.

After reading through these responses I'll start wrapping it less.

I was thinking tailgate hangups would be more related to using incorrect rubber-bands or other methods (e.g. too much tape) - thus my question.

I jump a fully-vented 315 Fox so perhaps with the larger size and rapid pressurisation I can get away with more wraps than I would with a different canopy.

Thanks Tom.

I've also seen a few openings where the tailgate seems to have prematurely released - but no hangups.

It was the result of a series of mistakes and bad knowledge.

Incorrectly installed tailgate (with extra rubber band)
Big rubber band
Only control lines into the bunch

You can see the photo.

I do not know what the average was. We should all know that 2 wraps, glue outwards is the recommended. That being said I have seen hang ups from too many wraps, tape that got damp and then dried, tape that slides down the line vs snapping on opening. The last time I used tape it was a double wrap and it hung up stalling my canopy on opening from a 180ft freefall. All but 1 of the hang ups cleared with releasing the toggles, the one that did not clear had multiple wraps of tape. Tailgates work so I will stick to that.
I definitely believe there to be a correlation between hung ups and "pressurization". So anything that would reduce opening forces could contribute to hang ups in my opinion.

Please define what you would consider to be premature. I am struggling to imagine a scenario where the Tailgate would release before line stretch.

Or do you think it could have a correlation with canopies having rolled noses or only 2-3 cells vented? I feel like some of the newer designs don't open with as much of a bang as they used to. It would also be interesting to know if they are more likely to hang up on uber deep brakes vs factory deep brakes. My suspicion is yes.

Any opening in which the tail is fully expanded before the nose is fully expanded.

A nose first (successfully tailgated) opening is one where the tail is fully closed when the nose is fully open.

A "full failure" would be a tail first opening where the nose is fully collapsed while the tail is at full expansion.

A "premature release" is basically anything between those two, although personally I don't worry about it if the nose and tail reach full expansion at the same time (or if the nose reaches full expansion ahead of the tail at all).

So for my purposes, I'd say the tailgate has released prematurely if the tail reaches it's full width before the nose reaches it's full width.




Or do you think it could have a correlation with canopies having rolled noses or only 2-3 cells vented?
I don't know. I've seen more of a difference between different canopy types than between different vent configurations, but that might also be related to the venting being different.

In general, I'd agree with you that a canopy with faster pressurization ought to be less likely to experience a tailgate hang up.



That would be interesting to test and/or gather data on, too.

Conceptually, I can see how more surge at opening would lead to faster pressure inflow and therefore more force on the tailgate, but I have no data to back that up.


I think I'll go back and look at canopy types. Offhand, I can think of a tailgate hang up on most canopy types, and I'm not sure if I'll be able to find a pattern there, but it may just be that our sample size isn't large enough to deduce anything meaningful yet.

At least she/he got that shit turned around so she was looking at the cliff.... Wait

I switched several years ago to only using a tailgate rubber band larks headed directly to the inside c like as a tailgate. I posted some pictures in a previous thread, but it's a slick way to use a rubber band without actually needing the Dacron tailgate. Also reduces the rare chance of the tailgate going through a slider.

I can't visualize how you would close it. Could you throw up a picture?

Thanks, that's interesting.
Is this the tailgate from the incident OP posted? Or a different hangup?

Yes, it's from this incident, picture taken after landing.

Would it be possible to repost that picture again please?
I've searched for it, can't find it.

rgds JS

http://www.basejumper.com/...post=2986378#2986378

Cheers

Sorry, are you using it(Rubbergate?/Bandgate?) slider up or down or both?
I`m just trying to visualize..
In those Picture you posted in the other topic..


..if slider up.. do you use your slider to lock it? (could it be than too hard to release?)
..if slider down..(might it release too easily?)

I think I know what you mean but plz take a picture if you could!

Sorry I was waiting to pack a slider down rig to take a few more photos as the original ones may not have been completely clear.

My long winded thoughts about tailgates:

When I first started jumping, I used a standard dacron tailgate. For some reason, I kept losing them early on (both tailgates and rubber bands), and within my first 20 jumps, switched to blue painters tape for no other reason than a friend was packing next to me and was using it, and I had lost my tailgate on the previous jump. I used 2-2.5ish wraps of sticky side in tape on all jumps for probably 1500ish jumps without any known issues. People have already pointed out the finer point of using the tapegate. Dont use regular masking tape (light brown, and can get hard or damage lines over time). Dont get any type of tape wet, and Dont tape just the brake lines (have since this once on video and once in person where the brake lines are taped together after opening)

Maybe 3-4 years ago, I was packing next to a friend, and noticed him using the rubber band gate shown in the picture. I couldnt really think of a reason why it wouldnt work really well, or be dangerous. It eliminated the need to carry around tape for me (I only lost 1 roll in 7 years!), and if one of the rubber bands break, I kept an extra in a mud flap. Ive had some rubber bands break after 10-15 jumps, but ive had them last for close to 100 as well. Seems like the quality of the rubber band and my initial cut seem to make the a difference. I initially just cut a small rubber band in half, but noticed both increased holding strength and durability by using about 2/3 of the width of a cut small rubber band.

Im not really sure exactly how strong the holding of the lines is compared to a tape gait, or a standard tailgate. It seems plenty strong to me to accomplish the job. Going back to the whole incident this thread is about, its interesting that I think ive seen more incidents with tailgates not releasing (now 3 I know of) than lineovers causing an injury. If I have a lineover slider down, I know what to do, and have a line release mod to quickly clear it. If I have a tailgate hangup, Im not sure exactly what Id do. Probably start pumping the brakes hard, maybe pull the risers apart?

To that end, I am a huge believer in asymmetric folds aka "The Tilley fold" as a preventative to lineovers as well. This technique can be a bit more difficult if you have a floorplate closing loop, but I think it does a great deal to keep the lines in the center of the packjob. I thought Id heard that Miles D actually doesnt use tailgates ever because of his confidence in this method, but not positive. I really think that everyone should use this style of folding when possible.

I used a tape gate on slider up jumps for a long time. As I became more of a believer in the Tilley fold, I stopped using them. I dont think theyre bad or wrong to use slider up, but I dont know how much additional benefit they provide over my current method either. Dacron tailgates + Large mesh sliders = scary! I have rubber bands attached to all my slider up canopies all the time, just in case. I guess I could do primary slider control with it, but I havent yet.

My final thoughts. Use a tailgate of some sort slider down, I like my method because its seem simple and effective to me. Theres nothing wrong with any type of tailgate when used correctly. Use asymmetric folds to combine with your tailgate to further reduce lineover risk.

(I just noticed the pictures are upside down, sorry)

What is it about using an asymmetric fold that you think is inhibiting line overs?

Would a symmetric Tilley fold achieve the same thing without creating asymmetries during the extraction phase?

yes

I think it all depends how carefully the folding is done. I feel like the assymetric folds create a nice cocoon for the lines to stay in, perhaps better than a two fold approach. I find that people are scared of asymmetric folds, but I have noticed no appreciable difference in heading performance from any other type of fold, as long as you dress the nose properly. If done properly and carefully, a standard symmetrical double "Tilley fold" should be fine, I just find the asymmetric version both easier, and seems to hold the lines in tighter to my brain.

I've used both symmetric and asymmetric folds and have had great results with both. I've not noticed any difference in opening/heading performance either. The Tilley fold is great!

To continue on that thread, I've stop using rubber band for a long time and one reason is that it was very difficult for me to find the good one.
So I found some rubbers that girls used for their hair. They are cheap, very fin and very solid for a long time of use. They have a great amplitude of tightening and it is easy to dose it. In addition they are fin so they glide easily on the sheath of the dacron TG.
For more than 200 jumps SD with them I've noticed nothing wrong for me.
Take care.

ps: on the photo (TG-rubber-fin) there is a knot because I broke it recently, I will change it.

Hello to everyone. I'm a jumper from this video. One of the reasons for posting this video is to tell to the others about incidents like this and to imagine how to behave in this situation if it will come. As for me, I have never seen tailgate hangups before - neither in the video, nor in reality. So that was a kind of surprise :)

I don't know who is that guy with "Ultras" nickname and why he wrote something here on my behalf. Let me explain how it was as real.

Before this incident I jumped with this tailgate (exactly with this!) about 30-40 times. It was manufactured by my guru, who taught me, not by myself. My friends, other base jumpers from my city, jump with the same tailgates made by this person, too (in summary - hundreds of jumps). And it was no premises

This day I packed as usual. I packed all red lines at the tailgate - not only control lines. I made 2 wraps of rubber because only 1 wrap was not enough. The rubber looked like it is a lil bit used and with a crack. I thought it will break immediately after any load on it.

After the jump I felt a movement backward to the cliff and pulled the toggles off, the movement stopped, but I felt that my canopy is uncontrollable and unstable. All I saw overhead was the red lines in some kind of bundle. That's why I think it was tailgate hangup. In ~4-5 metres from the ground the bundle dissolved so I can't say what exactly it was. I have some photos, I'll attach it to this post. This are not screenshots - just photos from my friend who were witness of this miraculous salvation

Thanx to those who sympathized that I met this incident, by the way my teeth are okay, I have only chopped up one tooth

What was the mistake? I think summary of factors: assist, my little weight with a big canopy, wide rubber.

Live and learn...

I know a girl that had a tailgate hangup using that exact method. Happened at the Perrine about 3 years ago.

It never stops to amaze me how some people keep wanting to re-invent the wheel when it comes to base gear, holy crap. The information needed for a proper, tried tested and true tailgate setup has been out in the open for how long? 15-20 years?

Kerkko
BASE1184

Me too.

Tom, just a question from my side to a pro .. (and to all others as well ...):
What are your thoughts about SD configuration with those kind of hangups? Could this contribute to possible hangups in a kind of way?
Would a No-Slider config might put a different outcome to that, due to the wider spread of risers while/after inflation?
just curious...

Thanks for posting. Glad you're OK!

Same exit, same method PCA, same rubber on your TG?


I think that for that kind of jump PCA or static (close from ground), the better is not to use a Tailgate and to pack Tail-bury...
In your case 2 wrap was too much, one wrap was enough...

Take care

I haven't seen any evidence either way on slider off v. down and tailgate hangups.

I've definitely seen them happen both ways.

Intuitively, I'm not sure that the slight different in riser spread is going to change the forces exerted at the top of the lines by much. But, as I said, I have no evidence, either way.

Not all the jumps from this exit and not all of them were PCA But the same rubber!) All the jumps were about 70-110m.

Hmmm, is it just me or do smaller people seem to be having tailgate hangups? Perhaps with the combination of less weight, smaller canopies and Zero airspeed deployment (PCA/SL) the force exerted on the tailgate is less likely to overcome the strength of the rubber band.

Does anybody know of a tailgate hangup on a canopy larger than 260?

Canopies do not scale linearly.

Hmmm wouldn't it be wingloading that could affect chances of a tailgate hang-up more than size of a canopy? I don't know myself, just thinking out loud

Larger canopies do tend to open harder. Skydiving and BASE. Obviously canopy types and designs introduce variables to this.

Yah that theory does fit the ones I know about. Tom how about your list?

It does fit.

I have not documented any tailgate hang ups on 280+ size canopies.

The largest canopies in my list are 260ish.

could this also be because tailgate hangups are very uncommon and canopy sizes above 260/280 are uncommon as well?

Intuitively I would guess no.

I haven't kept a record of all the jumps I've seen with no tailgate hangup, but my gut feeling is that I've actually seen more done on 280 and 310 canopies than on 240 and 260.

I think there is some truth in this and would expand on it in this way. Wave mechanics plays a big role, not only in the lines but maybe more-so in the fabric. Some lineovers may happen because of a whipping action in the fabric and lines from a combination of factors including canopy inflation/pressurization speed and weight/mass in the harness. I see these factors playing a large part in popping the tailgate off too. Tailgate hangups may happen because of inappropriately applied tension that doesn't allow for the whipping action of the fabric or lines to pop the tailgate off. At low airspeeds, light loading(she said she was jumping a bigger canopy), extra rubber band wraps, large rubber bands, etc, the tailgate impedes the opening and the expansion of fabric enough to a point where little whipping action occurs at the point of the tailgate attachment. Asymmetrical inflation and the lines included in the tailgate probably play a role as well.

Question: Did the jumper only have the red steering lines in the tailgate or were the center C and D lines included? What color are the center C and D lines on this canopy?

Also from looking at the pictures of the deployment the tail pocket looks like it's getting whipped which turns the tail inside out slightly which could change the tension and the dynamics of releasing the tailgate.

These videos have some decent explanations of some of the forces that occur during the whipping action and I can see where they could apply to fabric expansion and line tension in canopy deployment.
https://www.youtube.com/watch?v=XuXQZYxdmmU

https://www.youtube.com/watch?v=g8dS3wXRu_0

I am wondering if seemingly small differences in airspeed during inflation would play a role, it seems like they could result in concentration of forces on the tailgate?

It was noted in this thread here that larger canopies, due to their increased volume, will tend to be fully pressurised lower than a smaller canopy of the same make.

http://www.basejumper.com/...ew_flat;post=2955530

So lets say for 2 canopies of the same model and wing loading doing a static-line, and one is a 240 and the other a 310, compared to the 240, it seems to me that the 310 will:

- have longer lines, so will reach line stretch slightly lower

- have larger volume to fill with air, so take a little longer to fully pressurise, and thus be fully open lower

- due to being fully inflated lower for the 2 above reasons, have a higher descent rate in the later stages of inflation

- this higher descent rate results in higher-speed air acting on what is also a larger surface area (canopy size).

- likely have a heavier jumper under the canopy, again at this slightly higher descent rate, again multiplying the force on the canopy during opening in the later stages of inflation

These seem to be a few seemingly small differences that actually could result in vastly different forces on tailgates between canopy sizes, and why tailgate hangups might be more likely on a smaller canopy.

I think you may be onto something here, but I would suggest that maybe smaller canopies simply can not apply the same pressure to the tail gate as a larger canopy due to their smaller plan form.

Been thinking about rubbergate.
Anybody see any thing wrong with this version?

Two small rubber bands cut both larks headed to line sheath, closing same as hjumpers pics, more symmetrically in my mind.

Same material rubbing against itself - there will be more friction and wear - bands more likely to break each time. That said, breaking force for that system should be low enough to not cause any issues