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does anyoine have a thought as to why my canopy opened and back surged on a 2 sec delay. my deeps are dialed and have served me well for many jumps(50ish) but this has happened twice now. once last year when i just set the custom deep setting and then again last night. i just did 5 jumps on this canopy sat with perfect openings so im wondering why it back surged last night.
does this just occasionaly happen?
thanks

Is this happening on opening, before you are grabbing and un-stowing or Before.

Being it is night time and you don't have a full visual of the canopy when it opens. Might be just that you are being to quick with your Break release/un-stowing on the opening. If you are real quick because you are super current and comfortable with objects. Your jump goes real good and your dead nuts-on with the Heading. Sometime if you are just in-the-zone your brain and motor skills are working faster than your Canopy is.
Bottom line is, You are being to fast on the draw . un-stowing before your canopy is inflated and the Canopy does the shutter and falls just a little before it fly's.
Might be the problem, If not your breaks are too deep or you Lost about 50 Lbs. before your jumped last .
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How Low was the No-Slider Jump ? sometimes if your Deep break setting is just riding the edge of being to deep. The effect of ( Being to deep on setting ) will only come out if you have a tail wind on Canopy opening . I know it does not sound right but sometimes when you get tail wind or quartering Tail on the Lower no-slider jumps. It will steal precious inflation from the nose is the only way I can describe it.

anyway just some thought. sometimes weird shit happens but cause of effect is hard to find.
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same thing happend to me put 30-40 jumps on my rock dragon with perfect openings no problem then two jumps in row on the same cliff jumping slider off with a tiny cross wind wind had slow back surge after opening it was the first time i had opened not hallin ass down wind. i jump a pretty light wingload and my deep breaks were a lil to deep. i thought well its only if i open into the wind which you dont really do unless you have a 180 but then you pull your rear riser and its not gona do shit. switched to my shallow settings and had a 180 a few jumps later i would have been fucked probly. probly would of stalled my canopy into the face of the cliff. might wana switch to your shallows. i have no idea what im doing though

thanks ray. good thoughts. maybe i was too fast on the toggles but no faster than every other jump i think.
i have 2 deep settings i was using the ultra deep one this past weekend. i am like a cheetah on the toggles but distinctly remember feeing i was sinking a bit more than normal and starting to fall backwards. so i popped em really fast and let it fly to get away from the object.
i have lost about 10 pounds since these were set up, not sure if that matters.
jeff

Was there a tailwind?

Pilots call this gust induced stall.

The wing, at opening, is not yet moving "in" the general airflow. As a result, the tailwind blows air from the tail toward the nose (opposite the direction it needs to flow to generate lift on the airfoil). As a result, the wing stalls. The stalled wing slides backward before it gains enough speed (through wind accelerating it, jumper popping the toggles, or canopy diving, or more likely some combination of those) to start flying.

no tail wind. cross wind at 3 mph. pretty calm night.

wouldn't vents help avert such a situation?

Vents actually appear to exacerbate the situation. The air flowing in through the vents has to go somewhere, and some fraction of it will be pushed out the nose, "thrusting" the canopy to the rear slightly. This both deepens the stall and adds very slightly to the backsurge.

Many moons ago, when bottom skin vents first hit the market, I had a FOX with very well dialed deep brakes, set to my body weight. Wanting the latest technology, I shipped it off to BR to have the Vtech mod added. When I got it back, my perfect brakes were suddenly backsurging.

The best way to eliminate the backsurge problem is to use shallow brakes. Not so coincidentally, shortly after vents appeared, this problem started cropping up far more often on the vented canopies. Shortly thereafter, and also not coincidentally, BR removed the deep brake setting from their canopies.

As a rule of thumb, I suggest using deep brakes only on slider down solid objects. For everything else, I'd use shallow brakes.

The things I've found that are most likely to cause this are:

Tailwind
Jumper loses body weight
Brakes are set too deep
Change in altitude
Change in temperature
Adding vents to the canopy (this never happens anymore)

I'm not sure if any of those apply to your situation.

like i said i have lost close to 8-10 lbs since i dialed them in. bummed if i have to change them out, im going to try my flik in the shallower deep setting to try and get my perfectly parked openings that ive been getting. im glad i put 2 deep settings on that canopy. i put a shallower option for places like moab where the alti is higher than portland.
the weird thing is is that this will happen on a jump then go away for awhile. its not a huge problem when it does because im on it pretty flippin fast but id rather not have it happen at all.

Interesting reading this. However, my sense is that this depends a lot on the aerofoil shape (ie, canopy type) so the experience with the Fox Vtec may not be general.

Now I understand why the Fox only has 1 brake setting!

I've not done a scientific survey of canopy types to investigate, but I've had backsurge on FOX, Flik, Troll and Blackjack canopies at various times.

i think that having only 1 setting on fox and flik's is frigging retarded! imho jumping anything but bridges in shallow brakes... you have to have your head examined!
ill never understand why apex does this. dont let my experience sway you from putting a second setting on a fox. my deeps are very deep. also why i put 2 deeps settings on all my canopys in case one is too deep for the conditions.
do any jumpers really jump stock apex shallow settings on short delay's?

Sure, on an antenna (for example) in a tailwind. The strike potential is almost non-existent, and the tailwind can make the canopy stall during deployment (and backsurge) when deployed in deep brakes.

I'll agree with you that having no DBS is not a very good idea for the vast majority of jumpers. But I've definitely met people who only jump bridges and terminal cliffs, and for them the shallow only set up should be just fine.

Ya that's what I think too. All depends in general on how flat a flyer your Foil is trimmed and how the plot is loading the wing. In the vented Flik I have never put a deep break setting in it but I have custom tuned the regular and Deep break setting on the V-tec's and most other canopies I have owned. All depends on how they are trimmed to fly and the pilot.
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ok, that makes sense.