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I have a pc that I was told was a 46... non vented zp. I was packing last night for a 360ft freestanding A... I just was thinking to myself.... hmmm... I should measure this pc... I layed it mesh up and measured the tape on the mesh and it was like 42.5... I was like.... hm... so I took bridle off and measured 44 exactly. That didnt make sense either could it be that this pc is constructed differently or because its zp that this may be considered a 46? I just knoew there are so many differences with pc constructuion and ways manufacturers label them and everything. any ideas/advice on measuring this thing and/or if it is safe for a go and throw off this object? My main concern is I will be approx. 3500 MSL... how much of a difference will this elevation make on this particular pilot chute if lets say it is a 44?

i couldn't/wouldn't tell you that the pc you have in your possession is safe to use. i will say that i regularly jump a 42 from freestanders ranging from 300-350. a 46 is 1661 sq inches; the 42 is 1384, a difference of 277 sq inches. then again, i'm using a good quality pc. who made the one you've got? i think that's the real question here.

jay

I too have done jumps from a 300 foot
freestander with a 42" vented ZP PC.

Different manufacturers label their PC's differently.

The measurement number (in your case 46) can refer to many different things. For example it might be the dimension of cut fabric (before sewing), or the dimension of the finished product, or the length of the tapes.

As an aside, the same is also (very) true of canopies. Carefully measure the canopies from different manufacturers, and you'll see that none of them seem to come out exactly as placarded, and they all vary differently.

If it's from a reputable manufacturer, I'd be more concerned with what they say to use it for than what number they've assigned it. If they say it's for go and throw from low altitude, then it doesn't really matter what the measurement is--that's what they've designed and tested it for.

that was go and throw as well? (0 sec)

Hello freefly_trumpet_guy,

Besides my visits to Twin Falls and Bridge Day,
all of my jumps are done within a few hundred
feet of sea level, hence I am NOT the guy to
talk with regarding high altitude BASE.


I have done a total of 12 jumps from freestanders.
They are one of my favorite type objects because
of the easier climbs and lack of scary wires

9 of those dozen were from 306' and 315' and
have used both a 42" AV ZP PC and 46" ZP PC,
delays have ranged between 0 to 1.5 seconds.

Hence I think from 360 feet anywhere between
0 to 1 second delay should be totally fine....

However, your profile is blank under jumps,
so is this jump #1? Ground crew? Landing area?
Have you flown the canopy before? Exit practice?

Of course, if you are experienced then just
please ignore the previous paragraph.