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For the last 20 years, there has been a minimum 42" PC rule at Bridge Day. Recently, with advances in BASE gear, we've had a fair amount of requests to permit 38" PC's. I'm interested in your feedback as we are contemplating a change in the rules.

Keep in mind that 25% of all Bridge Day jumpers are first time BASE jumpers. Please consider any unique situations that may arise, such as throw-and-go's with a 38" PC, before you make your decision. Many thanks!

Not that it is a big secret but there are those that register with a 42 but use a smaller PC.

With that being said I think you should allow a 38 for BD.

But then who is experianed? Some people have hundreds of BASE jumps but still are beginners.

Then youwill have the people that complain just to complain. Some will say NO NO black death. Some others will say why am I not considered experianced?

If you can keep it simple, go for it, I vote 38 for experianced...

What experience would you require if you limited who could use the 38" pc? jump numbers seems obvious, but what about jump type (SU v SD/off)?

Did a little testing earlier this year to answer my own questions. Did a 2 sec slider-off flat-and-happy with a 38, as opposed to my normal 42. Asked a very experienced (500+) basejumper to watch my opening from below (it was a 600' E). I didn't tell him why I wanted him to watch. Opened perfectly, felt no difference at all. On landing, I got a "Looked fine to me" from my buddy. He was casually surprised when I told him it was a 38".
Throughout the next couple of days, I proceeded to exclusively jump the 38 ranging from 1/2 sec to 3 sec delays. All openings were consistent with what I normally get out of the 42", with the (expected) exception of the 1/2 sec delays... pins popped fine, but just a tad longer getting to line stretch, and still very safe.

So... would I give a first-jump guy a 38 for a throw-and-go at BD? No. He might need the bigger PC to help extract a canopy 1/4 sec faster when he ends up tumbling head low. That would be my only reservation against a "38's OK for everyone" policy.
For anybody else who has even a handful of basejumps, a 38 on this particular object should be completely safe.

Nic,

Not sure about the definition of "experienced" in this particular category, but I would estimate anywhere from 25-50 BASE jumps to jump a 38" PC. I doubt anyone would consider a 25 jump wonder "experienced", but it should be enough jumps to render them safe enough to fall flat and stable and deploy at the intended freefall delay.

We're not the BASE police and we have never checked anyone's logbook for anything, but we also need to watch out for the handful of "free spirits" out there who are willing to gainer their second BASE jump.

Great feedback so far, thanks! What number of jumps do you all think is adequate to jump a 38" PC at Bridge Day?

I think 38's should be allowed. A simple rule would be - slider up - 3 secs+ = allowed to use a 38"

Jason, the manufacturer of my BASE gear recommends a 38" pilot chute for delays between 4-7 seconds. What reasons do you have for me to not follow this advice at Bridge day? Thanks.

I suggest you create a definition of "experienced" and then use it to allow whatever various things that you wouldn't want a newer jumper to do.

As an example, which I believe is similar to what you already do, you might require jumpers to be "experienced" to use the diving board, and say that "experienced" means 25 jumps.

Then, you might say that only "experienced" jumpers (using the same 25 jump standard) would be allowed to use 38" PC's (on delays of 4 seconds or more).

I don't think you should try to police this stuff (i.e. measuring PC sizes at the exit or checking logbooks, or whatever). Just go with the same type of honor system that's been working, and I think that 99% if jumpers will follow the rules. The other 1% wouldn't be following them anyway, and checking up on them would just turn this into a game of "how can I get away with it?"

Adam,

I "inherited" the 42" PC rule after taking over as the BASE Coordinator. Now I'm simply trying to do what's right and permit 38" PC's that have been used for years. I posted this poll just to make sure I'm not missing anything. Our sport has no formal guidelines, so polls such as this provide some of the most valuable and accurate data. If your BASE gear manufacturer says to use a 38" PC for 4-7 seconds, then we'll accommodate that.

Tom,

As mentioned in another post, we have never looked at any logbooks or measured any PC's at the exit point - nor do we plan to. Unfortunately, we DO have someone almost every year who brings a 28-32" PC to the gear checking table. If we didn't have a PC rule in place, someone might die. If we didn't do gear checks right before people jump, we would have a death every other year (more info here). Sad, but true. The only thing we'll do this year is what we've always been doing - checking PC sizes at the Holiday Inn. And it looks like 38" PC's will be OK for Bridge Day this year.....

PS. I'm constantly trying to juggle two things: (1) Minimizing rules for jumpers and (2) Keeping the Bridge Day Commission/NPS/Public happy by having rules. When someone gets hurt at the Perrine, we often say that it was the jumper's fault and nothing changes. When someone gets hurt at Bridge Day, I've got the Associated Press asking me why I didn't have more rules in place.

I think it's a good question and thanks Jason for posing it. The range in delays is huge among jumpers there. It can go from a go and throw to a 7.5 second delay. Has anyone towed a pilot chute at Bridge Day in the last few years. Not that I can remember.

You know, many pilot chutes do not measure to their quoted size. I have several pilot chutes made 10 years ago that were quoted as being 42'' but they are actually 38 or 39''. Seeing videos of jumpers from years ago at Bridge Day jump their single pin rigs with their small pilot chutes, it's shocking that more accidents didn't happen. Pin rigs with too much pin tension is just asking for disaster. To me, it would be cool if there was a do-s and don't-s of gear in a handout at the event that spans from skydiving rigs to velcro rigs to base pin rigs. Course it would have to be something that wasn't necessarily a bridge day sanctioned article since any flaws in the article would be The issues to me for the beginner are pin tension, closing loop too large such that the end of the pin (circular part) can go too far and lodge, and most importantly attaching the pilot chute properly. And not using weird packing aids with the pilot chute that can be left on it.

I was with Walt Appel at Bridge Day several years ago and he had a bad limp on the Saturday night. I looked at him astonished and asked what happened and he responded with pride "rough landing but my gear is dry." I responded with "Walt, if you ever do that again and I'm there, I'm going to throw your rig in the water and give back to you soaking wet." And I meant it. Gear is expendable.

Anyway, I'd be glad to do some brainstorming with you Jason offline.

I wouldn't think it would be a too low of number if you required 20 STOWED jumps in order to use the 38PC.

I have low jumper numbers and even lower
stowed jumps, 33 and about 8 respectively,
so I am not arguing a position...just curious.

Could you please explain to me the difference
between deploying a stowed 42" PC and doing
the exact same thing with a stowed 38" PC?

Assuming of course that both pulls were after a
3+ delay and neither of the PCs have a handle.

I think your criteria for using a 38 instead of a 42 should be more like(at the end of the video waiver):

I solemnly swear I will only use a 38" PC instead of a 42" PC if I can either pull stable or at the correct time during rotation, so that I might not scare the living bejeezus out of Jason Bell and his staff by getting my bridle snagged on me somewhere and towing my PC along for added excitement.

Maybe I should of also put in "of varying delays consistent with those typically taken at Bridge Day, i.e.: 2-7 seconds."

Also 20 was just a number off the top of my head. More experience is never a bad thing, but, heck 10 would PROBABLY be sufficient. Next time I attend (when there is a longer jump window OR I live on that coast) I will be utilizing a 38" or 42" PC, whichever is more appropriate for the particular plan I have for the next jump. I don't think the rule of only 42" PC's will be around by then, because neither of my above criteria will occur this bridge day.

For what it is worth.

I have done some handheld hop&pops with a 32 inch, and several BOC 1 second delays with the same size PC. Altitude about 100 meters. On all jumps I had about 10-12 seconds canopy ride.
I only use 2 PC's: 32 and 42, on all my jumps. But then, I am experienced.

Ronald

Why is everyone talking about adding an experience requirement for using the recommended sized pilot chute for their planned jump? All the gear manufacturers have general recommendations for using certain size pilot chutes for certain delays. I have not seen a single reason here why ANY jumper should be forced to not follow their gear manufacturer's advice at Bridge Day (experienced or not)! WTF?!?

because it's not a matter of 38" being a proper size PC - but a matter of a person being able to take the 3sec+ delay. Watch some BD videos - you will see people pitching before their feet leave the ramp.

Maybe the rule should be that anyone using a 38" PC
must go stowed since most first timers go handheld.

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With that said, the economist in me views most
decisions as a simple "Cost-Benefit-Analysis" so
what are the costs and benefits of allowing 38s?

Benefit: I'd guess softer openings for experienced
guys taking deep delays, like 6+ seconds.

Costs: Extra effort on the part of Jason's staff when
checking gear and maybe an ever so slightly higher
chance of a newbie getting broken.

I see no reason to change the rule. Allowing 38" for experienced jumpers will only create more of a hassle for the staff and possibly make it more likely for inexperienced jumpers to use a 38, as the thought of using a smaller PC to make the opening softer for that long delay on the first jump may not have otherwise occured to the new jumper while practicing for a slow gainer out of a cesna. Besides, how many experienced BASE jumpers have a big issue with breaking rules?

why not keep it the way it is? you can go slider up or down, if you feel the need to go low push the slider up...KISS(Keep It Stupid Simple)

It's clear that this is a brainstorming thread intended to assist Jason in making an apparent rule change about this topic. It is not trying to force anyone to use gear inconsistent with that of their gear manufacturers recommendations. I did my first BASE jumps at Bridge day, two slider down HH planned 3 second delays. I nailed it exactly (on video) and yes I got slammed but I was okay with that. However I would bet that most newbie types pitch at closer to one second, even far less. But again this is just brainstorming.

 

I am with tree. Plenty of 38's getting jumped. Keep the rule protect the newbies.

using a 38 for a delay > 6 seconds, it's not the convenience of a soft opening but it's the danger of extreme center cell strip that can cause problems. i've used 42 inch pilot chutes on 8 second and the openings are funky.

i always use a 38 but i regester with a 42

i have serval videos of Sean BASE621 freefalling 1-1,5sec delays 230ft whith a 42´avzp pc on a velsro rig and non vented canopy.. he did just fine...

i usaly use my 42 down to 230-250 range then i use my 46ávzp for freefalls in the range 250-180ft...

i would say a 38´should be ok from BD..my concern would be centercell striping by the 42 on deep delays from that altitude..

but as one said.. hh=42 stowed=your allowed to use 38´...

Adam,That manufactors recomend how to use the gear is more a guide line to me than anything else..
IF BD require else its their choice... people shoulnt jump if they dont agree.. also all gear manufactors are pressent at BD rigt? then you also signal that its ok by BD rules...

just my o.25...

keep in mind that there will be 200000 spectactors around that bridge, there are no reason to push it and put the sport in a bad light..not this day, so whats the big deal with using a 42" and stay conservative, you guys have 364 more days to do 1 sec canopy rides

you might want stop throwing first timers and people whith less skydive experience than usaly recomended off that brigde that day aswell if yoy think of reputation of BASE.. but thats another tread which pop up each year anyway...

Besides using a 42´ on a fat delay (still landing dry) stil put alt of stress to the system compared to the 38´ so which is more conservative?

rember use the right tools for the right type of jumps.. Becourse its bigger dosnt mean its safer... its one one of the "IF´s".. and i guess thats why Jason brourght it up..

Don't allow first timers at Bridge Day? Many of us were still crapping in our diapers and smearing it on our faces when Bridge Day began throwing "first timers" off the New River Gorge Bridge. Also, is having a 100 jump minimum too little nowadays? Geez. Faber, I know you put a nice little smiley face next to your comment about Bridge Day, but you've always ragged on our event despite the fact that you have NEVER been here. If you ever do drag your butt over to this side of the pond in October, I'll pay for your BD jump ticket!

At a minimum, this thread has educated a few people as to the proper size PC to use for various delays. We will allow 38" PC's this year.

Mate if or more WHEN i go to BD ill pay my ticket like evryone else..

As you know i always were againts the newbies*7first timers at BD but i also think its a damn cool day..

Its like my wife.. i love her(yeah really),but i cant stand her mom.. but hey.. its a part of the pack right

Faber, I'm looking forward to meeting you sometime soon! My offer for a free BD jump ticket still stands, although our weak US dollar makes a jump ticket sound cheap to our overseas friends...

well ill take your offer my freind i just didnt want special care(well said wrong but you get the point)

It wont be soon as im recovering from a fib n tib break

But i whish you guys the best anyway

 
we`hell....i don`t know why you bringing up that part..i have never mentioned it...but if we should go back to the original question..you mentioned "fat" delay...THAT is the part were the word conservative comes in the picture...but hoooolihops.who cares now anyway..Jason have now announced that 38" is allowed.......so fire up, and pull under the tree level,YAHOO!!!!!!!!!

Keep the rule the same. there is no need for more rules and regulations at Bridge day.

We haven't added any rules this year. Actually, we're allowing you more freedom by permitting 38's.

If BASE manufacturers say to use a 38" for a 4-7 second delay and you plan to perform a 4 second delay, then why should I require the use of a 42"? Just look at the poll numbers above.

Diameter is not ratiometric to drag for different methods of construction. Barring assymetricality comes my following observations.
Definition: Skirt sag: the distance midway between reinforcement tapes to skirt reinforcement tapes to skirt.
38", 42" are pattern sizes meaning cut size, not finished.
that being said about cut and finished sizes, this has nothing to do with the effect that skirt sag can have on drag. Theoretically a 42" cut PC can have less drag than a 38" due to skirt sag.
IMHO, you should have a different determiner than diameter. ("I got a crap PC but it's a 38").Maybe approved manufacturer 38".

Drag extracts the canopy not the diameter of the PC.

The attached photo shows only a relative differential distance between the distance midway between reinforcement tapes to skirt vs reinforcement tapes to skirt.

Example 1:

 
Drag extracts the canopy not the diameter of the PC.

The attached photo shows only a relative differential distance between the distance midway between reinforcement tapes to skirt vs reinforcement tapes to skirt.

Example 2:
Take care,
space

If we shouldn't measure diameter, than what do you suggest? We only measure PC's at BD to insure you're not one of the boneheads trying to use a 28", which happens way more often than we'd like. We're not gear experts or hand holders.

How is the reaction from this "Boneheads", when you adress this people onto her serious miscue?

Bringing a 28" PC to Bridge Day with the intention of using it on a 2 second delay shows a serious lack of parachuting knowledge, among other things. My gear checkers won't harass you for this offense, but rest assured that you're still a bonehead.

Ratiometric of finished diameter/skirt sag. Let us call it FD/SS. get this from each of the Equipment manufacters and their take on it and make a standard. Post your FD/SS (Finished diameter/skirt sag)
Take care,
space