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Hi Folks,
Last weekend I did 2 hand held jumps from an Antenna and a bridge (both around 255ft). Those were my first go&throw jumps with my new gear. All other jumps were slider up, PCA or stowed (2 seconds delay or more) so not really good for comparison. On these last jumps I noticed that the canopy took a longer time (than I would expect) to open. I jumped with 2 friends and they had the same impression. Watching the video today I was able to count 2 seconds from exit to canopy inflation for my friends and 4 seconds for me (obviously I know there is an error margin counting seconds on video players).
Here is the data for evaluation:
My gear: Flik 280, 5 vents, 12 jumps. Apex DP7 made for a 300sqft (canopy packs "fluffy"), 48 ZP PC
My friends gear: Fox 245 & 225, 50 -80 jumps. Apex rigs with tighter packjobs (48 and 46 ZP PCs)

Yesterday I was getting ready to pack when something came to my mind. I have the large FLIK logo on the bottom skin. I remember that the first time I handled the canopy I was really surprised with the size of the logo and how heavy the bottom skin felt with it. The logo is an applique that almost doubles the amount of fabric on the bottom skin.
Question: Could this extra material be making the canopy heavy enough to slow the extraction and inflation? Does anybody have experience with this (i.e. jumped equal canopies with and without large logos)?

I will open the video file today with Pinnacle Studio and make a more precise time comparison (frame by frame).

Thanks

Seeya

Ronaldo

I have just captured the videos with Pinnacle Studio and was amazed to see how close the measurements were. The results (measured frame by frame):
My friends jumps: 2.47s; 2.37 (in tenths of seconds)
My jump: 2.83
Delay was considered to be the time from exit (both feet leaving the object) to inflation (the first moment the canopy gets a rectangular shape)
It is still hard to believe that we were able to feel such a small difference in time but if we use basic Physics (which work well for short free falls):

V=V0+gDt => V=gDt
(V)^2= (V0)^2 + 2gDs

If we consider an average free fall of 2.5s:
Ds=(g(Dt)^2)/2 => Ds=(9.81*2.5^2)/2 = 30.6m (100.4ft), this means we fall about 100ft in a go & throw.

The final speed would be about => v=0+9.81*2.5 = 24.5m/s

If we continue to fall until 2.83s the resultant speed will be => V=0+9,81*2.83 = 27.76 m/s

The distance traveled from 2.5 to 2.83s would be => Ds= (27.76^2 – 24.5^2)/ (2*9.81) = 8.7m (28.5 ft)

Of course this calculation does not consider air resistance but I believe a difference of 8m (26ft) wouldn’t be far from reality

I had no idea of how precise BASE jumping needed to be

So NOW I am really confused. Are you Ronaldo, or are you Ronaldopn?

Both. Ronaldopn was created specifically for BJ.com and Ronaldo is my username at DZ.com. Recently I discovered we can use the same profile on both sites .
I guess this happened because I posted the messages using 2 different PCs. I will delete ronaldopn later.
Thanks for bringing it to attention

Hey Ronaldo... like you know I have a FOX 315 with a huge logo on it... just free felt 70 meters a week ago.... hand held, 48 zp pc.

It opened around the midle, pretty much like my rock dragon 303 non-logo.

For sure there is some difference, in my opinion, BUT some pin tension here and there can F$*&#^CK all formulas and calculations.... so... just take care on this item and enjoy the ride.

According to your calculations you are going lower than your sissy scared friends.... good for you.

Cya.
Andre.

i would think with the addition of the 5th (center) vent it might even things out??? if the logo actually would cause a problem..

ive never heard of this though??

i jumped a Fox 265 4vents and a loggo before with no notice of a delay of a delay (30 ish" jumps)

question 2:

how do u like yur 5 vents set up??

i have always heard that bigger canopies take longer to open. and you do have a bigger canopy than your friends'. different model as well.