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Anyone experienced any difference in using a 46 or 48novents in <1 sec delay? Looking at the drag force table, the difference is minimal under 1 second. I was wondering how many feet you can save/loose in opening height, if you can.
I'd like and try in a 300 ft object, in order to understand if I'll get one more second in canopy flight.
Suggestions? Advices?

canopy size?, landing area?, object type?

canopy 225 troll mdv
object O (a smostake look like)
tight landing area between streets, poles and trees, that's why I'd like to add few feet in opening hight (but without static lined it).
By the way, I already jumped it, but I felt with no margin for errors in landing (i.e. if you get a 90 opening or worse...)

90 off headings are pretty common so you should plan outs if you won't make it to the LZ with a 90.

With a 225 I don't think you will see a difference in performance between a 46" and 48", both will extract the canopy efficiently. I jump a 280 and use a 46" on most 300ft jumps, lowest being 200ft.

With the correct exit and pitching technique you can save a couple of feet and open within a reasonably consistent height, but 90's will come your way if you jump it enough.

Will not affect PC performance

Object type could effect the PC performance. The object could allow wind to push or delay the PC.

And something else to think about, will a 48-46" PC deform a smaller canopy like a 220? I don't know, I haven't jumped a canopy that small since AFF.

True, but if it was a large canopy like a 310 with a lz that's a little further away you might want to go with a 48" rather.

Object type definitely changes PC selection.

On a span, I'd choose the 48 unvented. On a cliff, I'd go with 46 vented for canopies up to 280, and 48 for 300+ canopies.

If it's a low bridge, I want to go unvented to reduce the risk of PC hesitation. If it's a cliff or building, I prefer vented to reduce the risk of PC oscillation generating an off heading opening.

Because the risks of each type of jump are different (off headings matter on some and not on others), the object type should definitely influence your PC selection.

Yes but selection is not performance. Doesn't anybody here understand sarcasm? I even put one of those fucking smiley faces and everything.

RE: Performance vs. Selection

Fledgling: Doesn't anybody here understand sarcasm?

Yep, got it and chuckled.

Yes the sarcasm came through very clearly

We here in the United States are not aware of sarcasm.

how much does a 48" PC oscillate on a 1 second delay ???

I think it mostly depends on how you throw it. If you can get a good straight up throw, the oscillation is minimal. If you throw hard to the side, I've seen some pretty good oscillation.

Back a few years now (I am 2 years retired from BASE so take it as you will), I carried out some [crude] experiments with 46 v 42 on low delay jumps (<=1+ sec delays from 220ft), and I found the 42 more consistent in initial inflation than a larger PC (I assume this carries forward to a 46 v 48), with also my experiencing a couple of PC hesitations with a 46 from this height).

With smaller canopies, I found little difference in using a 42 against a 46, and "sometimes" the 42 was more efficient in the initial inflation stage, and thus dragging out the canopy earlier (albeit minimal time difference), than the 46. This obviously may have more to do with the method of deploying the PC than anything else (maybe someone has other evidence through video etc. that either backs up or disproves the findings/thoughts on this initial inflation hypothesis – I didn’t used to jump much with video).

However, sacrificing chicken head on, although I was sort of happy with taking a 42 with <= 1 sec delays on low altitude for a period of time (this might be due to being very current and at heights I was particularly active with), I always then reverted back to the 46 being the weapon of choice on these lower jumps, as it ‘technically’ made more sense to me than the experience.

You also wrote earlier : " If it's a low bridge, I want to go unvented to reduce the risk of PC hesitation. If it's a cliff or building, I prefer vented to reduce the risk of PC oscillation generating an off heading opening. "

So are you saying that on a cliff or a building, you are basing your pc choice on the assumption that you use bad technique as you also know that with a proper throw the oscillation is minimal? Should you first learn a proper technique to reduce the oscillation before going in to more technical lower objects? For me it is a no brainer that if you violently throw a gigantic PC to the side, for sure after inflation it will swing above the jumper and create obvious risk of sub optimal deployment. There fore don't do it! Problem solved. :) Personally I have never understood the need of vented pc's and currently dont use them and have not seen any serious oscillations or an strange behaviour in my deployments.

Yes. For sure.

I usually choose my gear and delay to make allowances for less than perfect performance.

I want to get a perfect exit, a good pitch and on heading opening.

Unfortunately, BASE jumps do not always go as planned. So I like to build in a margin for error in case I do not perform as perfectly as I'd like.

I believe that preparing for things to happen in a less than optimal way is a good practice, both in BASE and in life.

Did you try it with vented or unvented PC's?

My experience has been the same as yours, but I've also observed that apex vented PC's (vent in the center) have a less consistent initial inflation. The best of both worlds appears to be PC's with a ring shaped vent further out (like the Toxic) but unfortunately those are often quite a bit more expensive.

I would also think that a vented PC will not improve this situation in any way. As far as I understand it, the venting should really only help to prevent the build up of oscillations due to excessive internal pressure. I personally don't understand how the venting will prevent any oscillation caused by poor technique.

My observation in the real world has been that the oscillations are less violent and end sooner with a vented PC. I think the vent helps to "dampen" the oscillations so that the PC stabilizes itself sooner.

By then the damage would have already been done though right?

Perhaps. But the deployment on a go and throw happens slow enough that I think there is still an advantage to the vented PC. It's along the lines of "crooked extraction" instead of "sideways extraction" but if I'm in that situation, I'll take whatever help I can get.

on a 225 I'd use a 42" toxic all day.

Does that day, include the night time? I've used my 42 toxic both day and night on objects as low as 240.

My canopy is a 240 BlackJack.

this whole thread is just silly.

if anyone goes by what someone on the internet says about any of this you're an idiot.

that being said, i've been freefalling things 3-400ft regularly with a 40 inch pc, dragging out a 280 canopy with negligible differences in comparison to 42s and marginal differences in comparison to a 48.

i make pc selection based on what is hookep up to my rig. not the object.

I've seen (had) a go n` trow from 115 meter object with 42" turn into a 3,5 second freefall a couple of times. And by freefall I mean time to pin extraction
So if that were to happen on a 250 footer, it would be a bit messy in the very straight meaning of that term

So for fucks sake, do not use anything smaller than a 46" on anything lower that 100 meters.

well, that's why you shouldn't go and throw with a 42!

You mean one time thing or is that your regular go'n'throw experience with 42? :)

WIth 3.5 sec delay a 36 pc would probably work already :)

It happened a couple of times, my point is that I would not have anything smaller than a 46 on such heights.

For sure.
How do you fold your PC? do you leave the ZP open r fold it somehow?

For slider off I prefer the simple classic way, fold the mesh in half, stown the bridle and cover with zp.