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Kirils

Velocity question

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Well this last weekend I got a chance to put some jumps on my PD Velocity demo. I really loved the canopy, it's nicest PD I've ever flown. Fantastic openings, grreat swoops. BUT...toggle and front riser input force was crazy. Pulling a toggle felt like I was under a 240 Manta. I got worn out using front risers! The canopy was loaded at around 1.7. Was this a fluke or do all Velocities require a fair amount of oomph to manuver them? (or maybe I'm just gettin' weak in my old age)
Thanks!
"Slow down! You are too young
to be moving that fast!"

Old Man Crawfish

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I do not find the toggle or riser pressure to be a problem on either of my velocities...

Are the toggles heavy or do they just take a lot of input to induce a turn? If it is the later, it is probably due to how the brakes are set, longer control lines to allow for better front riser use. If it is the former, I can't comment because I have not had the problem...

the front risers are a little heavy, but certainly manageable...

mine are loaded at 2.1 and 2.25:1...

Josh
All that is necessary for the triumph of evil is that good men do nothing. - Edmund Burke

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I didn't notice an unusual control range. It just took more effort to use the risers or toggles. I just called
PD and spoke about this problem this morning. They acknowledged higher forces were required on the risers and toggles as opposed to other comparable canopies; but it would drop off some as the dive speed increased. It was their opinion that my light loading was a contributing factor.

I'll be trying a size smaller later this year.
I am not knocking this canopy at all, it is an incredible performer with solid predictable flight characteristics. I can't wait to jump the next size.
"Slow down! You are too young
to be moving that fast!"

Old Man Crawfish

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It was their opinion that my light loading was a contributing factor.



This is true, my 120 has much higher riser pressure than the 111. I was told by the factory pilots optimal wing load is in the 2.0-2.1 range for riser pressure anyway. Also, make sure you're not spiralling down to the pattern, that will also make the riser pressure higher (i've found).

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Also if the brake lines are too tight (maybe on a demo) you might be pulling the tail down a little bit when you grab the front riser (making it hard also).

I've found
FX @2.0 kinda hard extremely hard if moving fast after last minute maneuver.

velocity at 2.1 little harder than above, and of course bad if you have too much speed when you grab it

VX at 2.2 even harder and it is very easy to have too much speed if you are sashaying to get a good set up.

The perfect method is to cruise along in full flight right to your altitude and turn location and start your carve or hook. Floating in brakes a litle bit will make the riser pressure lighter at hook time due to the slower speed.

What makes these canopies much so advanced is that once you are moving extremely fast it is harder to put in more riser correction for your turn or carve into a swoop lane.

Canopies like the vengeance (1.7) and even more so the competition Cobalt (1.9ish) are much easier too zip around to your perfect turn area then execute your maneuer with lots of corrections because the pressure is very low.

Rumor has it that the smaller canopies tend to have lighter riser pressuer at the smae wingloading...well I weight 195 pounds and my friend Levin weighs 120, if we are both loaded at 2.0 he is a smaller wieght suspended beneath his canopy and ...well if he can do more chin ups than me maybe he thinks his riser pressure is lighter;)

He can do a 540 and I can barely do a 360 on my fX or VX...course I don't land that way I do carving 180s....:)
ramon
"Revolution is an abrupt change in the form of misgovernment.", Ambrose Bierce.

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In right behind you Ramon. Like I have already seen some of the experienced canopy pilots state; The higher the loading the lighter the front riser pressure. A year or so ago I demoed a Velocity 103 and I didn't like it because the front riser pressure was to heavy. But since then I am now under a Velocity 84 and love it with much lighter riser pressure, even less when I jumped Brittany's 75. (Very few 75's made, I think there are only like 8 or 9 out on dz's)

And as for you and Levin loading the same you have to take into effect that even though ya'll are loading the same his lines are shorter and may affect riser pressure.

Bryan

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>Rumor has it that the smaller canopies tend to have lighter riser pressuer at the smae >wingloading...well I weight 195 pounds and my friend Levin weighs 120, if we are both >loaded at 2.0 he is a smaller wieght suspended beneath his canopy and ...well if he can >do more chin ups than me maybe he thinks his riser pressure is lighter;)

Chin ups on the ground is a "static" exercise but it's very different when it comes to pulling down a riser during a high speed carve: imagine that you and your friend are doing the same carve with the same canopy (different size, same loading). Both of you are going to take the same G's, let's say 1.5G (probabely more actually).This means that during the carve your suspended weight is gona be close to 300 pounds whereas your friend's will be 180 pounds. Now put 2 or 3 G's, do the math and that's f*#k'in heavier for you! Just my thought...

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I jump a VE-103, while I was in Deland I was talking to a friend of mine and we were talking about the power in the velocity flare. The canopy like other cross braced cascaded lined canopies are very rigid and very fast. The toggle stroke is going to be more strong compared to a more mushy canopy like a stiletto because it is not as rigid and the airspeed and lift is not nearly close to equal. So you get a canopy they will surf because you cannot blow through the flare stroke, and its freaking solid. The front risers are going to be heavier just because you have a canopy that wants to lift out of your hand. I load my 103 at 1.85:1 which is considerd lightly loaded for the model.

One thing I have noticed that many pilots to not think about as far as the velocity is concerned is that they think you have to pull it out of the dive or you will take it into the ground. Ian Bobo told me that the velocity will recover back to level flight if given enough time. The perfect swoop is one that you are coming into your surf without any input after the initial impulse from the front risers, That is how Ian then Shannon (with a combination of rear risers) were able to break the swoop distance records. No wasted energy pulling it out of a dive. The key then it to start higher up and let the canopy come out of the dive on its own.

Jonathan
Jonathan Bartlett
D-24876
AFF-I

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. I load my 103 at 1.85:1 which is considerd lightly loaded for the model



if you were to go to a higher wing loading the front riser pressure will be noticeably less. ***Please note, I am not saying you should***

I fly a 1.85 and a 2.0 loading back to back and I can definately tell a difference, the higher wing loading will be less "heavy", seems counter intuitive, I know. the trick is also to spiral high if you're going to do that, cause spiral to the pattern and the riser pressure will be much higher (g forces and all that).

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Ian Bobo told me that the velocity will recover back to level flight if given enough time.



Does it really achieve level flight or does it return to its natural glide angle requiring some input to generate more lift and fly horizintal? If it does achieve level flight, how does it do it? I believe you but I can't figure out the physics that would make this happen. Thanks.
Rich M

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Ian Bobo told me that the velocity will recover back to level flight if given enough time.


Depending on the canopy and wingloading, some canopies will "level off" or even climg w/o toggle input after an aggressive dive. Smaller, highly loaded canopies generally will not "level off" and will, after an aggressive dive eventually slow back down to their normal "full flight" mode w/o ever leveling off or climbing. I have seen a Stiletto 120 climb a little in a swoop w/ zero toggle input, my VX-60 does not plane out or level off w/o some toggle input.

Hook

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Ok, let me clarify, these characteristics are based on a canopy that is not grossly over loaded. Through extensive testing the velocity has been found to be at optimal between 2.0-2.1 :1 A canopy is not going to come out of a dive when loaded at like 3.0:1 Its just going to drop out of the sky, great for speed events, not good for distance though. My 103 will completely level off after an agressive dive as long as I have started it high enough so it can recover on its own, If i am too low I will either have to pull it out with input or I bury myself into the ground waiting for it to recover, but thats why its a radical canopy.

Jonathan
Jonathan Bartlett
D-24876
AFF-I

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Wether a canopy will plane out w/o any input is determined by drag. If the there is enough drag on the canopy, it will "rock back" and the lift vector will be vertical and the canopy will plane out. The lager the canopy, the more drag there is. Even loaded at 2.0-2.1 I doubt if my VX would plane out, there isn't enough drag on it.

Hook

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Would the shape and trim of the airfoil not also come into play here? If the airfoil is able to generate true lift with the increased speed from a radical input then it is concievable to think that any canopy could level out with out input if it was able to generate lift reguardless of drag. Also the momentium of having a jumper swing infront of a canopy sould change the AOT and point the canopy up and back to level flight.
Yesterday is history
And tomorrow is a mystery

Parachutemanuals.com

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Would the shape and trim of the airfoil not also come into play here? If the airfoil is able to generate true lift with the increased speed from a radical input then it is concievable to think that any canopy could level out with out input if it was able to generate lift reguardless of drag. Also the momentium of having a jumper swing infront of a canopy sould change the AOT and point the canopy up and back to level flight.



It isn't the momentum of the jumper swinging foward, it is the drag of the canopy wich causes it to "sit back" and change the lift vector and angle of attack. A small canopy has less drag, which is why a Stiletto 97 at a 1.5 wingloading is faster than a Stiletoo 150 at a 1.5 wingloading.

Hook

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