Bottom Skin Vents

[guest]

Anybody know anything about vents in the bottom skin?

I hear that BR is going to start offering them as an option on foxes. Do they actually help?

I heard that CR played with them several years ago and discarded the idea. Anybody know why?

If anyone has any info, I'd appreciate it.

Thanks,

--Tom Aiello

[guest]

I got to see half a dozen static line jumps from less than 200' some with and some without the VTEC mod. Some I saw from above and some below. The VTEC top skins cracked open simultaneously with the bottom stretching out. It is remarkable to note that those with had longer duration rides and traveled further. Those without had shorter rides and some in fact had stuttering openings or put another way the top skin pressssurizing a second or second and a half later than the lower. The sink rate during the studderring was nothing I'd want to land!!

[guest]

Were these canopies all Foxs of the same size?

[guest]

BASE JUMPERS -

I've got about 100 jumps on the VTEC, from 175 feet to 1000 feet to terminal - Wingsuit included. On terminal or slider jumps there are no disadvantages when jumping the VTEC and the only noticable advantage is on accuracy - you can sit in deep brakes much longer and still land softly, but on jumps with slider off or down, there is no comparison. With a VTEC canopy you get a solid flying wing instantly (no more surging or mushy canopy to deal with), riser or toggle input to correct off-heading openings responds quicker because the wing has pressurized faster, on-heading performance seems to have increased noticably, and again, accuracy increases with the constant flow of air into the cells via the bottomskin thus fully pressurizing the canopy.

The issue of mesh on the bottom skin may may be a concern to some, but all you have to do is take a look at the durability of pilot chutes. The only disadvantage that I can see is the possibility of snag potential if you are to land in a tree, but how often does that happen, and if you do land in a tree - you've likely done some canopy damage anyway. The construction of the mesh vents where the mesh meets the fabric is approx. 4 times stronger than the fabric itself, so there is not a chance of a "blowout" of a cell.

The advantages of the mesh vents far outweigh the disavantages of adding vents. The only two disadvantages I see being the snag potential, and the cost of the vents - which is easily justified .

I don't know what CR did in terms of venting canopies (maybe Adam can enlighten us), but VTEC is the way to go, and the only canopy I will jump anymore. When you combine the flying characteristics of a FOX and the VTEC, you have a far superior canopy. I've got two F111 VTEC canopies and I've just ordered a ZP topskin VTEC which I will specifically use for lower airspeed slider off or down jumps, and slider up jumps. When I jump non-VTEC canopies, I've just added a new variable to compromise my safety. Consequently, I will not jump non-VTEC canopies any longer when I jump slider off or down, it's just not worth it!

573

[guest]

they were a mix of size and wing loadings

[guest]

you say:

"I've just ordered a ZP topskin VTEC which I will specifically use for lower airspeed slider off or down jumps, and slider up jumps."

Just what's left to use your F111's on?

Sorry, couldn't resist.

[guest]

Not to take away from your observations but until we match canopy to canopy (including various manufacturers), site to site, deployment to deployment....enviroment to enviroment...we have no foundation to empirically base our subjective views, reaching an objective opinion........

This by no means defers from what we are leaning.....
The collection of data to reach an opinion is just that....

the synthesis of a conclusion demands the collection of all data
otherwise it's just that, an opinion based on too many variables


"do not re-invent the mouse trap when you're still learning how to smell the cheese"

[guest]

Keep an open mind friend. You'll probably be able to come to a conclusion someday. I don't claim to be a scientist just an observer.

[guest]

Hey Dick,

F111's can be used on anything between lowER airspeed jumps, say below 300 feet, and when a slider can be used, say above 600 feet. Let me say it another way: F111 between 2 and 4 second delay on slider off or down jumps. ZP topskin/VTEC less than 2 second delay How else can I say this? Ahh! Use ZP topskin/VTEC below 300 feet and when a slider is used - above 600 feet. Does this clarify things for you?

573

[guest]

I was under the impression that a ZP topskin combined with bigger PC's might be detrimental to heading performance - I've never jumped one so I have no first hand experience. If so wouldn't it be better to jump the F111 canopies on lower solid object jumps due to the fact that you won't get much distance from the object?

Anyone like to put me right?

Craig

[guest]

I was under the impression that a ZP topskin combined with bigger PC's might be detrimental to heading performance - I've never jumped one so I have no first hand experience. If so wouldn't it be better to jump the F111 canopies on lower solid object jumps due to the fact that you won't get much distance from the object?

Anyone like to put me right?

Craig

[base515]

What happens during a wall strike? Will the vents help or hurt?
mike

[guest]

Jumped the ZP VTEC 5 times last weekend and I stand corrected. ZP VTEC is OK with 3 second delays. The openings were easily tolerable, even with 8 pounds of cameras on my head...