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Hello,
What is an estimated gain in canopy life with ZP topskin (1/3rd of chord)? For a $1800 canopy the option costs around $200 which is around 10%. How much more life can we expect from it in relation to conventional construction?
Thanks

Interesting question, I'm keen to hear if it does extend the canopy life expectancy.

I've got a new canopy and one with +-180 jumps on it with some patches on it (same canopy manufacturer). The flight characteristics are almost identical with no visible additional wear on the zp section of the old canopy.

I however purchased the CUS for the performance befits. I like the idea of having a fast opening canopy that can sink in really well, and fly to far landing areas.
I also love the flair power of my canopy.

Don't do a cost benefit analysis on base gear unless you are setting up a business. Buy the best gear you can afford for the type of jumps you will be doing.

ZP top-skin may affect packing, opening and glide. Base your decision of those factors rather than CBA.

Yep.

But I do think it can lengthen the service lifetime of the canopy, as well.

In my experience, ZP foreskin canopies get about 30% more jumps before they start to get that "too clapped out to flare" feeling.

That's just one of the factors you should consider.

In my opinion, if you are comfortable managing the ZP nose, it's a good option to have. If it gives you trouble, though, you're likely to see a much higher off-heading rate.

If it's your first canopy, I'd skip the ZP.

If it's your first ZP canopy and you're having trouble with the nose, I'd stay off the slider down, solid objects until you have made enough jumps/pack jobs on it to be confident of the heading. Taking a trip to a good span for a longish weekend can help quite a bit.

Thanks Tom, if I get around 30% more jumps I can say it is worth the money. It is my second canopy and I never had any troubles packing. It shouldn't take more than a couple of packjobs to get used to it.
And I have just the right span for the tests

Thanks but I don't believe packing would be a concern. In this case either option would fit my types of jumps, it is just a matter of evaluating if it would be better to pay $2000 to make (X+Y) jumps or pay $1800 again after only X jumps

A group of us did a night load off the
old potato span and the only guy to
make it to the main LZ was Jeff, on
a newish BlackJack with ZP nose.

Good point, ZP flies better at night.

Anyone jumping a Fox with ZP nose?

Good point, ZP flies better at night.

Slight head wind was stronger than expected...
water at the Perrine was at a 10 year High so no
beach landings hence if short you have to put it
down on the trail, day time no problem, but at
night with little-to-no moon, kind of tricky but
we digress, the point was in my previous
subject line.

Was anyone on the load jumping a non-ZP blackjack?

Comparing different canopies won't really give you a good feel for the glide/penetration of the ZP option, because the differences between the underlying canopies is more significant than the ZP/F-111 difference.

The Blackjack has better penetration than most other BASE canopies on the market today, so I'd expect the Blackjack to travel the furthest into that headwind unless you had a Seven on the load, or a highly loaded Flik (and assuming no one was on the front risers, or that the Blackjack jumper was on the fronts as much as anyone else).

I'd bet money not one guy
used any risers that night!

Okay, Fair point, it was the
Only BlackJack on the load.

Do you think, ceteris paribus,
a ZP nose helps increase a
canopy's wind penetration?

I think it depends on the age of the canopy.

If the canopy is brand new, the flight performance seems very comparable with or without the ZP. As the canopy ages, the difference in performance seems to be larger. Basically, I think the part-ZP canopy flies "like new" longer and that's also the reason for it's longer service lifetime.

Almost everyone in my crew jumps an Apex tarp (Flik or Fox) loaded around .7, but I'm the only one with a ZP nose, and I consistently out fly everyone. For the purpose of eliminating other factors such as delay we can use a local bridge as an example. 190ft or 160ft exit, SL Exit, straight in landings, i can outdistance anyone on the load.

What is the age of the canopies?

As a canopy ages, the glide and forward speed degrade noticeably.


Is your canopy a Flik or a FOX?

The Flik has substantially better glide and higher available speed (i.e. more penetration) than the FOX.


What is the wind condition on those jumps?

A canopy with higher forward speed but worse glide angle (i.e. someone riding the front risers or jumping a highly loaded canopy) can outdistance a canopy with better glide angle if you are jumping into a headwind. The converse is also partly true--canopies that have less speed can outdistance faster canopies when jumping in a tailwind (this is part of the reason that so many skydivers advise using rear risers to get back on a long spot--they are trying to slow the canopies progression along it's glide slope to expose it to the helpful tailwind for a longer period of time).

The more important "gain" is how much the ZP adds to your operational envelope and thus your safety margin. That $200 will pay for itself ten times over the first time its extra performance saves you from a trip to the emergency room.

Absent the packing issues Tom mentioned, I think getting the ZP nose is a no-brainer YES.

BRILLIANT!

Craig