Basejumper.com - archive

In BASE different people have different experiences that in turn leads them to form different opinions and view points.

Tom's article on "My First BASE Rig" is generally an excellent article and my experiences in BASE lend me to agree with most of it. However there are a few points made by Tom that I disagree with, or my preferences vary somewhat. That isn't to say that Tom opinions are wrong and my opinions are right. My intent is simply to give the reader a different point of view (and many different points of view commonly exist in the BASE community).

If I do not address a point in Tom's article then by default it means that I agree with and support it.

Option: Secondary Inlets
Bottom skin (secondary) inlets (also known as "vented canopies") have made a major safety improvement in terms of jumping low objects and also in terms of avoiding object strike under canopy.

Bottom skin inlets do not add any complexity to packing or in the use of the rig - in fact the jumper doesn't even really need to be overly aware that they are there (much like they are not overly aware of the load tape configuration in the canopy). The jumper will simply use up less altitude when deploying slider down, and the canopy will respond better (and use less altitude) when the jumper pulls down on a rear riser to avoid an object strike. A vented canopy will also be harder to stall when doing a deep brake approach.

These attributes make the canopy more reliable and much easier to use under certain conditions. I therefore believe all beginners should purchase a canopy with bottom skin vents as this will lower their chance of injury.

The many beginners/low experienced jumpers I have witnessed using canopies with bottom skin vents have demonstrated excellent control with these canopies and have not experienced some of the problems frequently seen with non-vented canopies.

The argument that beginners should not jump objects where object strike is an issue is not valid in the real world. It is not long before the low experienced jumper will want to progress to more challenging objects, and they will often do this without purchasing a new canopy (for economic reasons). It is also better that the progression to more challenging objects be made with a canopy that they have the most experience jumping.

Tom states in his article:
"They may also create some poorly understood, but relatively undesirable phenomenon, such as opening backsurge in deep brakes. ......no beginner should jump a system that has poorly understood effects of any kind.

The back-surge phenomenon is actually very well understood by the manufacturers however a degree of misunderstanding does exist about it within the general BASE community.
If a canopy without bottom skin vents has its brakes set too deep it will stall on opening. A vented canopy will stall just as a non-vented canopy will stall if its brake settings are too deep. However if the brakes on a vented canopy are only slightly too deep, then it will surge backwards on opening but not completely loose cell pressurization as a non-vented canopy will (this is better than a regular stall). The issue here is primarily the brake settings - not the bottom skin venting.
When the Vtec FOX and the Blackjack (both vented) canopies were initially released to the market, their factory set brake settings were slightly too deep and a back-surge would often result. Thus the fear of "vented canopy back-surge" was first voiced as people didn't equate the back-surge to a stall and simply blamed it on the bottom skin vents.
Since then the manufacturers have worked out factory brake settings on their vented canopies and this is no longer an issue.

Cons of bottom skin vents:
At this date all canopies made with bottom skin vents have valves. (Older Vtec FOX's can be retrofit with a valve). With well designed valves the only cons are the additional cost (which is insignificant compared to the medical cost of a broken bone), and harder openings at terminal velocity. To counter the harder opening at terminal, the use of a small-marquee mesh slider with vented canopies provides excellent results. Most manufacturers will supply a small-marquee slider upon request.

Option: Multi Bridle Attachment
I have definitely experienced an improvement of the consistency of openings at terminal with a multi bridle attachment. Sub-terminally there is no solid evidence that the multi will improve openings, however there is ample photo and video evidence that shows the multi delivering the canopy to line stretch in a form much closer to how you packed it than when compared to a canopy with a single bridle attachment point (which deforms the packjob significantly during extraction).
There is an argument that a packjob that reaches line stretch in a neater configuration may have a lower malfunction rate over the long term (tens of thousands of jumps).

I would mainly consider this option if you plan on doing a significant amount of terminal jumps (for example if you live in Norway). The increase in complexity is very minimal and any beginner should be able to grasp it within a few minutes of examining the system (as hundreds of beginners have done so in the past).


Recommendation: Flik Vtec by Basic Research or Troll MDV by Atair Aerodynamics
These are my two most preferred canopies which are currently on the market by a very long margin. They have superb all-round characteristics and beginners are currently using these canopies with excellent results. Opening heading (both slider up and down), flight and landing characteristics are all fantastic.
Both canopy are very easy to use and are very predictable which makes them a great choice for beginners.


Avoid: Any unvented canopy, Blackjack
If your goal in BASE is to minimize the risk of injury as much as possible by having the best possible equipment, then do not purchase a canopy without bottom skin vents. Un-vented canopies require much more skill to successfully deal with an offheading close to the wall (this scenario happens to everyone eventually). Also the cell pressurization speeds on un-vented canopies are more variable making jumps from very low objects more of a gamble.
The Blackjack canopy has flight characteristics that are harder to master and this canopy (although having other excellent flight and landing characteristics) is generally not recommended for beginners.


Containers:

Recommendation: Reacter 4, Basic Research
This is only a personal preference as there are plenty of good velcro rigs out there, however the Reactore 4 (in the loose fit option) is very easy to pack. It was designed to conform to the shape of the packjob, rather than make the packjob conform to the shape of the rig. Because the rig is easy to close there is less chance of distorting the packjob in the process which may contribute to an offheading opening.

Secondary Recommendation (Pin): Gargoyle, Morpheus Technologies
This is simply the best pin rig on the market, hands down.

Pilot Chutes:
In addition to Tom's recommendation I also recommend getting an Apex Vented 38" from either Consolidated Rigging or Basic Research. This is the best sized pilot chute for delays in the 4-7 second range (basically anything sub-terminal slider up) and also for all wingsuit BASE jumps. The order in which you purchase your pilot chutes will be determined by the order in which you access different types of objects. For example, if you are going to Norway then you would buy a 36" p/c before you embarked on the trip. If you planning to jump your first 1000' cliff then you would buy a 38"AV p/c. As you jump a wide range of objects you will probably end up owning the following pilot chutes: 48", 42"(vented), 38"(vented), 36"(F111, small mesh).

Option: Big Grab Toggles
I recommend beginners get stiffened toggles. You loose height under canopy with the brakes set much faster than when the brakes are released and the canopy is flying. It is common to see a beginner (and sometimes experienced jumpers) fumbling to grab the toggles after opening.
Stiffened toggles do not require any additional skill to use, they just lower the chance that you will fumble for the toggles and loose valuable altitude in the process. Fumbling for a toggle resulted in a wall strike and severe near-fatal injuries of a jumper with 1,273 BASE jumps. Stiffened toggles may have (by the jumpers own admission) prevented this accident.
See attached photo's of the big grabs in use (plus a 5 year old skysurfing photo thrown in for the hell of it).

Thanks Dwain!

For those of you who don't know him, I recommend reading carefully everything Dwain has to say. He is, in my opinion, clearly the world's top BASE jumper.


I know that some very experienced Scandinavian jumpers (by virtue of their location, I'd bet they do quite a bit of terminal stuff) have removed their multis because they felt the multi actually degraded their heading rate. While I don't agree with them (I jump my multi on every jump that I'm using my multi-equipped canopy), I think this is worth noting.

 
Thanks for that - good to read different perspectives from the experienced guys. Do you recommend newbies get the 5th upper control line fitted if they buy a canopy that doesn't already have it?(ref: your article on ABA).

Thanks

Will

I might beg to differ...on the other hand, since when do I know anything?!!!
That said, I think all the best BASE boys and girls start out in Oz...we push the envelope where most don't dare to go!

Thanks Dwain and Tom for making the effort to answer questions and trying to make basejumping safer for all of us.

I agree with Dwain that you should mention you experience level so people know on what you are basing your opinion on. My opinion are based on just two 245 FOX vTec canopies and I have about 400 jumps on 245 FOX vTec canopies. Did only 30 jumps on one of them and the rest of the jumps are on the other.

My vTec FOX (pretty old and not retrofitted with covers ... yet) with a multi. I do agree with the fact that the canopy opens faster with the multi and that if you are jumping low objects or are pulling very, very low it may make a difference. But I have removed my multi because my off-heading frequency increased using it.

Not only did my off-heading rate go up but the off-headings was more violent especially if it was around 90-120 degrees off-heading. It was not unusual for me to have to push against the raisers to prevent my body to induce a linetwist. The problem with this are that it takes time, time that are better spent correcting your heading then pushing on your raisers.

Please forgive my poor English. But I still think most of you prefer bad English over Swedish ;)

PerFlare
Member Team Bautasten

can the multi bridle attachment be removed and installed easily? Or is it a big hassle, what I mean is, when youre jumping things where object strike isnt an issue really, and an offheading would not be that bad, like a span, could you install the multi, and then if youre doing something where offheading is a real threat, take it off? I hope my question is clear

Yes. It should take an experienced jumper/rigger less than five minutes to remove or re-attach the multi.

However, even with the multi itself detached, the canopy top skin still includes the extra reinforcements used to attach the multi (and still costs the extra $150).

right, has anyone done this? What is their experience with the extra reinforcements effecting deployment?

If the multi is not hooked up, the additional reinforcement points don't affect anything. Just pretend they're not there.

I may be wrong, as I do not jump a multi equipped Fox. The two Foxes I owned were single bridle attachment (per the advice of more experienced jumpers I talked to when I was looking for my first BASE rigs.)

Can you tell me the "noticable" differences in taking a 36 compared to a 38 to terminal.

Thanks

Michael

I'v jumped a 38 at terminal a number of times, and it seemed to be fine. Then again, these were jumps with good separation from the object - if I was pulling close to an object I'd go down to a 32 to avoid center cell strippage.

Peace,

D-d0g

You are correct for 99.9% of jumps.

On a McConkey, the multi attachment rings can create an extra snag hazard (I once saw a tattooed Aussie try to fish his attachment ring out of a crack that it had fallen into, while standing on the edge with the canopy below him--it took him about 10 minutes of heart-stopping tension).

skreamer:
Yes I personally recommend the 5th upper control line for everybody jumping a Vtec FOX.

PerFlare:
While your results with the multi are very interesting I would say that they are not at all typical or representative of people's experiences with the multi in general.

Everyone has different experiences with equipment. I personally have had runs of over 100 BASE jumps in a row on multi equiped canopies without an offheading of more than 15 degrees. I have been told that in every BASE competition since late 1999, the component that judged heading control was won by a multi-equipped canopy (don't quote me on this as I don't have the data).
If I was doing a jump where heading was a serious life threatening issue and I had a choice of two identical rigs except one had a multi and one did not, I would use the canopy with a multi (but once again, this is my own personal preference).
These things are not proof that multi-equipped canopies open better, but simply the vast number of multi jumps done (estimated at well over 100,000) without widespread reported heading issues (no more than single bridle attachment canopies) are an indication that in general, they do not have bad heading rates. As with all BASE technology, people's individual experiences may differ.

When people are having bad offheadings with a particular canopy (and the cause is not obvious) the first thing I tell them is to try is to jump the canopy with a different container. This fixes the problem about 80% of the time. The problem is usually not the canopy, but the combination of the canopy, the container and the way the jumper is packing that canopy into that container, plus a number of other variables (this is where the multi may come into play). Changing just one of those variables usually fixes the problem. The problem often lies with the combination, not with an individual component.
If you modify the combination by changing a component and it fixes the problem, then this is not absolute proof that the component was purely to blame.

Mac266:
Differences between a 36" p/c and a 38" p/c. First I was referring to a 36" small mesh F1-11 p/c versus a 38" large mesh ZP p/c. The 36" small mesh F1-11 p/c will probably pull about the same as a 34" large mesh ZP (but with more stability).
Noticeable difference at terminal: You won't usually notice a difference but your pack job will - especially if you are using a single bridle attachment point.
The purpose of a pc is to extract the canopy from the container to line stretch as fast as possible while minimizing the destruction of your pack job (center cell strip, end cell slump, tail pocket slump). By using too big a pc you increase your change of an un-predicable opening, offheading and a malfunction (especially slider up line overs).

Take two jumpers, identical in every way including equipment, except one has a 40 inch pilot chute and the other has a 48 inch pilot chute. They are both jumping freepacked canopies with a single bridle attachment. They both take a 3.5 second delay. The jumper with a 40" pc will most likely reach full cell pressurization higher (and with less potential problems) than the jumper with the 48" p/c. Although the 48" p/c will extract the canopy to line stretch faster, it will destroy the packjob far more in the process which in turn will mostly likely result in a slower canopy opening. At line stretch, a neater pack job (even tension on all the lines and symmetrical exposure of the bottom skin to the air flow) will usually open faster than a deformed pack job.

This same principal applies to using a 38"zp p/c at terminal versus a 36"F1-11 small mesh (or a 32"zp large mesh).

Addition to my original post:

Inflatable Tracking Pants.
This recommendation is somewhat tentative as the technology is still very new to the BASE world. However I have personally witnessed and heard many reports of beginner BASE jumpers using this technology with great results and no problems whatsoever. As long as the beginner has done a number of skydives using the pants to become very familiar with them, then they should have no problems using them on their first tracking BASE jump. The pants will result in the jumper tracking further from the object making an offheading much easier to deal with.
At this stage I can see no negatives using this technology for any BASE jumper of any experience level. Bird-Man.com is the only company that sells this technology at this time. The technology was invented by Robert Pecnik (co-owner and Design Director for Birdman).

I can vouch for this.

I'm totally convinced now that my heading issues were related to how I packed the rig. I did 20 slider-offs the past week and every single one was dead-on heading. All I changed were a couple of things in my pack job.

This brings up an interesting question though... what are people's thoughts on doing an mix-n-match approach (such as my CR Ace in a Vertigo Warlock) vs. staying with a particular manufacturer for the entire rig (e.g. a Flik in a Reactor, a Dagger in a Warlock, an Ace in a Perigee).

Intuitively, it seems the latter would be preferable, as the manufacturer would be using their equipment to all of their design, testing & tweaking. Would it be reasonable to assume that this would lead to a more "optimized" configuration?

Thoughts?

Manufacturers don't test their gear in other "mainstreamed" containers or with "mainstreamed" BASE canopies? Can someone verify that statement? Thats pretty sloppy if its true...

Well, I didn't quite say that, because I don't know exactly how each manufacturer tests their gear. So I'll retract that part of the statement.

I think it's fair to assume that one cannot optimize for everything and everyone, so a manufacturer will natrally favor their own products. This is an assumption, I have no facts to back it up.

Still, I think the question is valid... if you had the choice, would you favor a unified or a mixed configuration?

why should they ruin their buissness?ofcours they should work to get the best out of their gear,and not think much about others.

Yo Zennie!
Thanks for bringing this up, I would be interested in statistical data or anything that has been studied regarding useing modern BASE gear from different manufacturers on the same system. For me personally at any given time, I may have a container from gear manufacturer #1, with a canopy from manufacturer # 2, and a PC from manufacturer #3...I'll pretty much use anyone's bridle as long as its 9'.
I've often wondered what the 'experts' think about this, I don't feel I'm doing anything dangerous as I am setting up my rig EACH time for a SPECIFIC jump.
Anyways, just hoping someone out there can shed some light, thanks for bringing it up Zennie.
Later
Blair

PS I kan't spel worth a fuk

I tend to mix and match like crazy, hence my Blackjack in a Prism and other non-homogenous rigs. I've found that I tend to have more trouble with a particular type of rig (see Dwain's comments on closing style combined with container and canopy) than anything else. I haven't had any trouble mixing the various manufacturers gear.

Why would a multi bridal attachment induce off heading openings?
If the canopy is brought out of the container more 'evenly' as with a multi....I would have thought it would have opened more reliably on heading..
Is it something to do with the cells on the left and right of the centre cell being brought into the airflow more evenly ....ie at about the sametime as the centre cell.....causing the possibility of unequal air inflow on the left and right side of the canopy?

Zoter: A multi is supposed to increase the chances of an onheading opening

added: also to reduce the chances of center cell strip.

FWIW I have my blackjack in a gargoyle and have had no issues with it.

Good opdate.

What about pilots handels ie No handel, plastik tube, internal, Eksternal and so on

Internal on 42, eksternal on 36? Manufactur differences?

Ove

I thought it was to reduce the chances of center cell strip.

I believe the idea is that if jumping in a crosswind or having the P/C pulling to one side rather than directly up it will effectively shorten one on the multi lines thus pulling the pack job out asymetricaly.

Zoter,im jumping multi heres my point of weiv on that point...

When your pack job is ok,the wind is ok and you dont tip a shoulder it will help you....ofcourse it will also help you better than that,BUT now think of a tipped shoulder,shortdelay whith heavy x wind,your PC is torn to either your left or right(compared to your freefall posissition) and you will have an uneven pull in the 4 lines,THAT im sure can turn your canopy...

Most cases i think the multi helps to get a cleaner openen which is the reasson i use it

correct

JP's got the explanation.

If you have a multi, try this: Pull the bridle off to one side of the container (as if jumping in a crosswind). See how one side of the multi goes tight (the one you are pulling away from) and the other stays loose (the one on the side you're pulling toward)? Imagine what will happen if a crosswind pulls the PC off to one side. One side of the multi going tight first is a bit like loading one riser first. It will have a significant chance of spinning the canopy as it moves to line stretch.

what are you current thought on the multi? Would you use them on everyjump or only on jumps without a X-wind?

My personal experience has been that the difference is negligible. I have around 350 jumps on a multi-equipped canopy, and around 200 jumps on the exact same canopy with the multi removed. In practice, I honestly can't tell the difference.

When the difference isn't noticeable, I'd say you ought to err on the side of simplifying the system, and just remove it.

Note that none of the complaints/arguments (theoretical or based on actual experiences) about the multi have any bearing on terminal jumps (which is what it was originally designed for anyway).

I've pretty much just left mine off, all the time. But if I was going to do a bunch of terminal jumps (say a Norway trip, or an elevator weekend), I'd consider re-attaching it.

If one were to buy a new canopy and had the extra money would you suggest buying a canopy with the multi?

Once the canopy is made (without a multi) you can't get the multi put on it. But if it's on you can always just not use it. Any thoughts on that?

It's very odd to see the name of the author of this thread again. The recenct addition to this post brought his name right back to the main page of the forum list. It's as though he had just posted yesterday.

It's strange to see his name, little avatar, and writing again.

He'll always be missed.

-=Raistlin

i deafently would get the multi,you can esaly take it off and use it as a single bridel as usual...

I havnt removed my multi for 1 jump yet(besides a skydive in my first fox 225 on a skydive),i do however use alot of time working if i should stow it in the sheet or not(sub 230ft it will be free in my harness).

i dont blame my on headdings to my multi,im just lucky that my twisted bodyposistion and poorly packed canopy works different and somehow gives me onheaddings most of mý jumps

Sure. If money's not an issue, then you can just use it when you want.

If money is an issue? I probably wouldn't bother. But, it could be nice for the long delay stuff.

you dont think it help much in the slider off envioment?
I has to disagree(just a thourght,and personal poinion),i think that the fact that you have 4 points lifting your canopy out of the container,makes the sequence(if you have the correct bodypossition,no hard x wind etc etc)more smooth in the time from were the canopy leaves the harness until linestrech(ie a more conststant pull).

I dont have much to compare to but have looked at some deployments from videos it often looks like an single atachment point canopy often(no matter if its a v tec or not),gets this ^ shape in the opening which i dont like.

Any thourghts? if im thinking right or wrong(i know im wrong in many ways,so lets just think in this multi issue)

only way to prevent the shape like ^ is bag or sleeve. fact is that on bad body position opening the multe offten makes the opening even worse.

i wouldnt say most... i have only jumped whith multi and can say that i often has been surprised on how good onheadings i got in different ways on both Fox and Flik(talking both hard x wind and bad body position as you pitch..
Ill dig up my calculation from 0-100jumps(didnt looked at it after) but i were surprised how good onheadings ive got compared to others.(looking at example Mac that whith his single bridel in many jumps had 90 offheaddings were i only got 1 180 10ish 90 then below that..(its rare i have more than 45 degree offheadding).

and dont blame my packjob for the headdings,i know i dont pack beautyful and many people wouldnt jump the packjumps i usaly jump..

i never saw my canopy does the ^thing.. perhaps as im using smal pc´s and multi i dunno,but i never saw it and cant see how they could be made if you use a multi?

I use my multi for slider up and take it off for slider off. I have not noticed any better preformance for the under two second delays with it on or with it off. I don't have enough slider up jumps to know one way or another.

Per Flare, If your out there let us know your thoughts on the multi today as compared to 2003.

i diddt say it were better,just that i like the consept.

if you takes it off if your making sub 2 secs jumps i guess you think theres a hatch on it in that envioment,could you tell so?

I have freefalled 180ft whith my multi on and had nothing bad from having it on there.

I do unsheet the cover from the lines below 250ft through...