I've read the earlier posts about the Vtec's performance at low airspeeds. Does anyone have any comments about how a Fox Vtec performs at terminal? How do the openings compare to a regular Fox of the same size? Are they any harder?
I've read the earlier posts about the Vtec's performance at low airspeeds. Does anyone have any comments about how a Fox Vtec performs at terminal? How do the openings compare to a regular Fox of the same size? Are they any harder?
Apparently the Fox with Vtec is not too different (a little more solid) to a Fox without Vtec when jumping slider up.
Can't comment from experience because This Great Southern Land has no terminal sites and I have been too lazy to test from an aircraft.
Any comments Anne / Todd ????
As for the lower stuff - I've nearly retired the electrical tape and gone the freefall option instead of s/l.
Quote from http://www.basicresearch.com/vent_technology.htm,
"The Vtec is designed for slider off or down openings. Openings with a slider up prove to show little difference in performance."
It has been our experience with the Vtec - mesh slider- that the openings are not any harder.
Would I recommend a sail slider? Not because of the Vtec. But maybe because of other reasons.
This is what we teach in our ground school when the topic of Mesh vs. Sail is being discussed.
To make that decision you must evaluate 3 things.
1- Canopy performance-
Factors include- age and performance of canopy, fabric type, line type, size, design, and more
2- Deployment airspeed
8 seconds and more
3- Opening point above ground level (AGL)
the closer to the ground the faster you will want an opening
If all of these lead you to want a sail slider then sail it is. If any of them lead you to a mesh then mesh it should be.
Look at these three scenarios with good canopy performance.
A– 1400 foot jump 9 second delay. What would you want to use? Most would say – mesh.
Why? Well canopy performance is good, so sail. Deployment airspeed is beyond 8, so sail. But, opening AGL is low, therefore mesh.
B – 3000 foot jump 12 second delay. What would you want to use? Most would say - sail.
Why? Canopy performance is good, so sail. Deployment airspeed is beyond 8, so sail.
Opening AGL is high, therefore sail.
C – 3000 foot jump 19 second delay. What would you want to use? Most would be confused.
Here are my thoughts. Canopy performance is good, sail. Deployment airspeed is beyond 8 seconds, so sail. However, opening AGL is low, then mesh. I would and most (in Norway) are opting for mesh.
The Vtec alone would not lead me to change the type of slider or choose a sail over a mesh.
Most jumpers are using the mesh slider even on terminal velocity jumps. Why? They usually can not afford any type of hesitation.
If you have any other questions feel free to contact us at br@inland.net
Todd
Basic Research
Todd,
How would you feel about your above scenerios with a ZP top skin.
Do I remember somebodies comment about getting spanked really sharply in Norway on such a jump?
Jon
I'm so scared of getting "spanked" that I opted for a sail slider on my Mojo in Norway. When the canopy had less than 10 jumps it was perfect. As the canopy grew older, the openings started to get a little too comfortable for my liking. I jumped my exact same canopy from an aeroplane and did a 7 sec delay with mesh slider and got really "spanked". Call me a woos or anything but I am really sensitive to high G decelerations, being a 36 yr old "spring chicken". I see many (most) people jumping in Lysebotn with mesh, some great, some really mega hard.
So, Todd is right. You have to analyse your parameters and determine what to choose. I won't jump full sail again with my Mojo, which is in good shape, but will make a combo mesh/sail slider with about 2/3 sail and 1/3 mesh at the leading edge, just to avoid that scary little snivel.
/Lukas
PS The sail slider is excellent incentive to track for the water :-)
7 seconds from aitplane ?????
but you have to think about the speed of the plane!!!!
i'm the same age as Lukas and a confessed opening-shock weenie. i jump my p-pro/mojo220 almost exclusively slider-up and swap sliders as frequently as pilot chutes. i have an oversize largebore mesh slider that i use from <2-4sec delay, the stock CR mesh slider that works great from 4-6sec, and a modified sail slider that's my favored reefing option from 6sec up.
the modified sail was built by CR to resemble a PD-reserve slider, with a square gore in the center which i have since had covered with reinforced fine mesh. as a rule, i have found larger sliders to function more cleanly and induce less canopy distortion than smaller ones. hence, my stock CR sail slider went into early retirement.
after paying tribute to the goddess of whack a couple of times, i have discovered that the proper selection of slider-control options is as important as the slider itself. it's vitally important that the slider remain seated at the stops until the canopy reaches line stretch. if one grommet starts down the lines before the others, heading, reefing, and opening performance may all be affected to varying degrees.
for short delays, well into what many would consider slider-down territory, i use a small tube-stow for my locking stow and may or may not use direct slider control (half-width small rubber band at center C-line attachment). 4sec or more delays will find my nose rolled, a double-stowed large rubber band locking and direct control on the appropriate slider.
with the pin-closed rig and smallish canopy, i also tend to size my pilot chute down a little. for example, using stock CR zero-p pilot chutes, i have enjoyed excellent performance from the 38" at 3.5sec and from the 32" at 6sec. to be fair, i do use the magic-mushroom fold at the low end of a given pc's range, though.
p.s.: had another sweet one off the Chrismas tower last night!
inky-black skies and good friends with landing lights!
http://www.geocities.com/webbslingr/
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