Velocity question

[freeflir29 0]

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My VX (2.1-2.2) does not plane out

But...But...Ian Bobo says........

[weid14 0]

Bobo says VX is an Icarus, next question please .

[VivaHeadDown 0]

So you are saying that as you dive, your canopy will match whatever speed you are diving at? So it will have the same terminal velocity as you, and "not plane out"? Why haven't we ever heard of someone turning points under canopy then? Why couldn't we dock a regular belly flier who can fall in the 100-110mph range or slower with someone under a highly loaded canopy diving. It's not unreasonable, according to the belief that your canopy will never level off with the horizon and so must fly as fast as you can fall.

I'm still in the 1.4 range, so maybe I haven't thought it through enough to the point you guys have. I hope you're not basing it all on the last 1000' or less of your flight when you really don't have enough time for your canopy to level off. Have you tried it higher? Why not try your carve around 2500', or open at altitude and start it then. sheesh.

"This one time, at band camp, I saw a guy dive from 30,000 feet and never level off! He just kept diving and diving. I yelled, no no no stop diving, but he didn't listen. If only he had known his canopy would never ever ever level off. The end." -Tall tales from swooper's journal

[freeflir29 0]

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Why not try your carve around 2500', or open at altitude and start it then

OK...I'm no Velocity pilot. However, I think I have a decent understanding of canopy flight. Now that we have that disclaimer out of the way.....I think you are misunderstanding what is being said. On a canopy like a Velocity NO it won't "return to level flight." It will....at some time...depending on loading and severity of the induced turn, return to IT'S NORMAL FLIGHT ENVELOPE. Ever try laniding without flaring? I have..I broke my tail bone on a Aeroglide 235 loaded about 1:1 maybe less. Try landing a Velocity loaded at at 2.0:1 without flaring. It's gonna hurt. On a canopy like my Stilletto loaded about 1.25:1 it will go into level flight. It will even gain some altitude during the recovery arc if you induce enough speed. A Velocity will not. The most "recovering" it's going to do is back to it's "normal" descent/forward speed envelope. As I mentioned if you try to land like that it will probably kill you. On my stilletto it IS POSSIBLE to land and only use the toggles to shut the canopy down. You don't have to use them to "plane out" the canopy if you have timed your turn perfectly. This "positive recovery arc" is NOT a desireable characteristic for most swoop god's. It limits the amount of speed you can induce and therefor puts limits on how far and how fast you can swoop. With a negative recovery arc ALL the control is in the pilot's hands. It planes out when he wants it to and not before. Of course, this also makes the canopy a MUCH more dangerous animal.

[VectorBoy 0]

I thought all canopies leveled off with induced speed unless you fly the round out with various amounts of maintained front riser pressure and harness input followed by a little bit of rears or straight to toggles transition? Glen.

[VivaHeadDown 0]

Could somebody who hasn't broken their tail trying to land a 1:1 loading, and does fly high performance canopies regularly, please interject here. I'm afraid we're going to go back and forth on this when an authority could settle it with what really happens.

The use of "flight envelope" doesn't seem to really be the right term, freeflir29, you may understand canopies, but your explanation didn't answer anything that I was addressing. Of course the more a canopy dives, the better swoop because the more speed. But to say that a canopy will continue to dive unless the pilot adds some sort of imput just does not make sense. In a continuous arc, sure. Swoopers have been clocked at incredible speeds. However, that is not the same. The pilot adds the input to keep the dive going (until the forces cause his/her arm to give up holding the riser). If the pilot lets up, I read you as saying that the canopy will NEVER recover from the dive. No matter how high it is begun. I'm not questioning that the current high performance canopies dive for an enormous distance, but I need someone who is flying one to tell me they started their dive at 13,000 ft and had to flare to avoid the earth.

Anyway, I thought using rear risers came before the toggles were applied, and that they were only used when the arc was nearly perfect so that the swooper leveled out just nearly perfect to the surface. The rear risers were not a good tool to level out, or a safe one, relatively speaking. And the use of toggles to level out would eat up too much energy in the form of drag. It would defeat the point of building up all that speed. Am I making any sense to you?

[jdhill 0]

I jump 2 differnt sizes, a 103 @ 2.1:1, and a 96 @ 2.25:1... I have competed in PPPB (1st in Intermidate Speed and 2nd in Intermidiate Distance) and this year's Pond Swoop Nationals (finished in the top half)...

In my experiance, my velocity(s) will not attain level flight without toggle or riser input (notice I did not say return to... they don't fly level to begin with, not with out inputs)... They will recover from the dive but they will only return to their normal glide ratio and return to their normal speed after a dive.

Note: I am not saying that Ian is wrong, only that MY canopies will not level out on their own... his might... each canopy is a little different (trim, brake settings, yada, yada)


Josh

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

[Samurai136 0]

I think you may be a bit confused. Any time a canopy is flying steeper than its full flight trimmed Angle of Attack it is "Diving". If the canopy is trimmed w/ a negative recovery arc it will continue to "dive" for a period of time after you release the front risers. That period of time is determined to some extent by the force of drag, momentum built, etc, etc. Since drag ultimately reduces speed, eventually the canopy will return to whatever it's full flight AOA is.

The Stiletto, Vengeance, Spectre, and Cobalt (as far as I know) are trimmed to fly flatter than say a Samurai, Velocity, FX/VX, or Xaos. Would a canopy stay "diving" for 13,000 ft? Probably not, and why would you want it to? I have seen a Xaos drop 1200ft on a 90degree riser to final and believe it could have continued to dive further.

And there was the Velocity--wingsuit in free-fall dock they acheived in Deland earlier this year. So it IS possible to have a canopy diving fast enought for a freefaller to dock....


Ken

"Buttons aren't toys." - Trillian
Ken

[Hooknswoop 19]

Let me take a shot:

After a front riser turn (or any diving turn for that matter) a canopy will do one of three things, if no input is applied to it.

1) It will recover from the dive to level flight, parallel to the ground, (again w/o any input), slow down below it’s “normal” forward flight speed (the normal speed at which the canopy flies at w/ the brakes released), then “surge” forward and accelerate to it’s “normal” forward flight speed again (back to the speed, attitude, etc it was in before the initial dive-inducing turn).

2) I will recover from the dive to its “normal” forward speed, w/o ever flying at a shallower angle to ground than it’s normal decent angle. If, for example, the canopy descends at a 35-degree angle, relative to the ground, after a hard/turn, say a 90-degree dive (straight down dive); it will recover back to the 35-degree descent angle. It doesn’t recover past it’s normal glide angle. So it seems to continue to “dive”. It really isn’t, but it just doesn’t “plane out” w/o riser or toggle input. Why is this an important distinction? If

3) Somewhere between 1) and 2).


Why is this an important distinction? If you hook turn a canopy that falls into 1) above, and you initiate the turn too high (say 20 ft too high), it will plane out 30 ft over the ground, slow down below it’s normal full flight speed, then surge towards the ground to accelerate back to normal full flight. Why is this bad? That leaves the jumper at 20 ft, with no airspeed and under a canopy that is diving to regain that airspeed. This is similar to flaring a canopy at 20 ft, almost completely, coming to almost a complete stop, then letting the canopy fly. So there you are w/ less that full flight airspeed to trade for lift to flare with. So the landing is hard. Most people respond to this situation by holding some brakes in to prevent the surge, and sink the canopy down to a generally “brisk”, “ankle-burner” of a landing.
So a canopy that behaves like 2), and not 1) is preferable for swooping, because if the jumper hooks it a bit too high, the worst that can result is a landing that would be identical to a straight in approach, because the canopy doesn't "level" off and bleed off all it's forward speed. You never slow down below it's "normal" forward speed, unless you add riser/toggle input.

Hook

[cobaltdan 0]

hey hook,

i dissagree.

some canopies after a hook will stay in an extended dive unil brake input pulls them out. (i generally reffer to these designs as having a negative recovery arc)

some canopies will have a natural recovery arc after a hook with no brake input that will effectively pull them out of the dive. (i generally reffer to these designs as having a positive recovery arc)

in the case of the later your final angle differs depending on the design of the canopy, ranges from returning to full flight, to a level swoop, to even a slightly climbing swoop.

i do not agree with your statement that positive recovery canopies if hooked too high must result in planing out too high then surging foward into the ground. that is simply poor piloting. the canopy will only surge as you described if brakes are used and released.

i also do not agree that negative recovery canopies are best for swooping. imo just the opposite. with proper placement of your hook turn a positive canopy is a more efficient swooper because you do not waste any speed or angular momentum stabing the brakes to pull out of your dive. where you come out of your hook (i.e. how much altitude you drop) is easy to govern throughout your hook by performing a carving hook and using counter or co harness stearing. additionally in general a positive canopy will continue to swoop at slower speeds than the negative.


what about improper placement of your hook? well if you execute a turn too low, that positive canopy has a much better chance of getting you out of the corner than the negative.

sincerely,

dan<><>
www.extremefly.com

Daniel Preston <><>
atairaerodynamics.com (sport)
atairaerospace.com (military)

[Hooknswoop 19]

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i do not agree with your statement that positive recovery canopies if hooked too high must result in planing out too high then surging foward into the ground. that is simply poor piloting. the canopy will only surge as you described if brakes are used and released.

I have seen many canopies plane out, and have experienced this under a Safire 189, with zero tiggle input. I can actually get my Safire to climb w/o any toggle input. It then slows down, slower than normal full flight, then begins to surge towards the ground, all w/o any toggle or risr input. I have seen a Stiletto 120 climb slightly with no toggle input, with the same result.

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i also do not agree that negative recovery canopies are best for swooping. imo just the opposite. with proper placement of your hook turn a positive canopy is a more efficient swooper because you do not waste any speed or angular momentum stabing the brakes to pull out of your dive. where you come out of your hook (i.e. how much altitude you drop) is easy to govern throughout your hook by performing a carving hook and using counter or co harness stearing. additionally in general a positive canopy will continue to swoop at slower speeds than the negative.

A canopy that will plane out w/ no toggle input requires releasing the front risers at exaclty the correct altitude to allow the natural recovery arc to plane it out exactly above the ground where the pilot wnats to be. So the input that determines the plane-out altitude happens well above the ground. If the canopy will not plane out w/ toggle input and the pilot releases the front riserrs a bit too high, the only thing lost is a bit of speed, and the pilot can plane the canopy out at the altitude they wish, becaus ehte canopy will not level out of it's out accord.

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what about improper placement of your hook? well if you execute a turn too low, that positive canopy has a much better chance of getting you out of the corner than the negative.

I think they have the same, either way you wil have "dig out" of the dive. If the have the same recovery arc, it will require the same amount of toggle to pull out. The diffference being if the pilot hooks the canopy that planes out w/o input too high, the landing is not a nice swoop. with the canopy that does not plane out on it's own, a too high hook, simply result is a slower swoop, still at the altitude above the ground the pilot chooses.

Learning to hook turn on a canopy that planes itself out can result in the pilot constantly being in the corner, because he knows a turn too high will not rtesulkt in a nice swoop landing, but a turn too low only requires a bit of digging to fix, resulitng in a slower, but still just above the ground swoop. So the pilot tends to hook a little low to ensure a nice swoop, then he hooks it a bit too low and can't pull out. I've seen this scenario played out mnay times.

Canopy pilots can look at both of our opinions, take what they think is corrct or works for them and profit by it. Differing opinions benifits all by allowing people to read, think, and decide for themselves. So iguess what I am saying is, let's not focus on "right" or "wrong", by offer our opinions, and heck maybe we can meet in the middle someday
Hook

[cobaltdan 0]

"let's not focus on "right" or "wrong""

ok....lets just talk flying style

stabing brakes to come out of a dive wastes some energy both by generating drag and wasting angular momentum. imo i believe some people prefer negative recovery arc canopies because the learning curve is quicker for those who like snap hooks. on a negative canopy it is easier for some people to transition to fast big air manuevers because placement is not as critical and you just stab out. this type of flying style is not the best on a positive canopy such as the cobalt. on the cobalt i prefer carving hooks. in this way you can control how much altitude you drop during the turn by shifting weight in your harness. shifting weight inboard causes the canopy to recover positively, shifting outboard causes the canopy to recover negatively. it is a different flying style and my personal prefference.

in competition you do not get points for aerials, i.e. "going big". you get points for efficiency (distance), consistancy and accuracy. as such i am seeing many competitors change styles focusing on the most efficient hook to swoop, such as i mention above....

give it a try sometime maybe 10 jumps or so and report back.

both styles and both types of canopies have proven competitive in competition.

sincerely,

dan<><>

Daniel Preston <><>
atairaerodynamics.com (sport)
atairaerospace.com (military)

[weid14 0]

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both styles and both types of canopies have proven competitive in competition

competitive maybe, but what is winning out there? canopies that are designed with a "negative" recovery arc -- right? Apparently there isn't enough inefficeiency caused by needing a bump on the brakes or rear riser input to plane those puppies out.

[PhreeZone 15]

If the Velocity returns to level flight accourding to their test pilots, I'd say thats positive arc. The Velocities have been kicking a lot of rear lately...

Yesterday is history
And tomorrow is a mystery

Parachutemanuals.com

[weid14 0]

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If the Velocity returns to level flight accourding to their test pilots, I'd say thats positive arc. The Velocities have been kicking a lot of rear lately...

Yes they have, and I believe if you ask the test pilots, they will tell you a little bump may be needed to help plane the canopy out. But what do I know.

[VivaHeadDown 0]

This is the kind of thing I was hoping to hear. It's nice that cobalt has someone up high piping in, as well as competitors who's techniques are based on their beliefs. I'd like to see if we can get some other canopy manufacturers in here on this one, or their test pilots. Any of those with good credientials lurking who are holding back some more info? Now's the time to share and teach!

[rhino 0]

My crossfire2-97 keeps diving.. Loading 1.9.

Rhino

[eames 0]

Competitor opinion: of all the "higher" performance canopies that I've jumped (Cobalt [email protected], Xaos-21 [email protected], Xaos-27 [email protected], Velocity [email protected], I didn't do well with the latter two in competition because of the ridiculously high wingloadings...) I've never experienced one with a "negative" recovery arc, as I've seen it defined here, though it may be a product of style. If you're style is conducive to achieving the greatest distance (i.e. more carving, less snapping) I've noticed that if you come back to the natural glide angle with more speed than the natural glide speed, you will continue to plane out (not necessarily to flat, but flatter than natural glide). I've been able to do this on all of the canopies listed above. Less easily with those loaded more heavily, though I've been able to plane out very near to flat with the Xaos-21 98 with no input. I'm sure I could have with the Cobalt, but I sent it back before I really dialed it in.... I believe it can be done with a reasonable wingloading (for the design) on *most* any canopy. That's why I'm in the process of moving to a larger canopy, maybe between 105-111.

Oh yeah, experience (this summer): 3rd ASC, 6th PPPB Pro accuracy in Perris, sucked at Rantoul, PSNs, and ME-- I learned the hard way why everyone isn't generally flying above 2.3....

Jason

[VivaHeadDown 0]

Thanks Jason. A lot of what you said sounds like what I learned while working at Perris. Though I have no formal training by going through Jim's school, I've watch tens of thousands of landings, and listened to what anybody had to say. After 9 months of that, I was coming to believe in what you were saying. As far as over-loaded, that was obvious back in Nov. when the guy tried to enter with a 3.1:1, and looked like a train wreck each time he tried the corse. Good luck finding the design sweet spot!

[weid14 0]

FWIW, from PD's flight characteristics book on the Velocity.....


Coming out of the dive:
The radius of the Velocity’s natural pull out arc is much larger than that of the Stiletto,
whether a riser or a toggle initiated the turn that started the dive. The difference will be even more
noticeable if you’re downsizing. Like most canopies, the Velocity will not pull out into level flight
completely unless some brakes are applied. (It will pull out to a flight path that is slightly flatter
than the normal full glide angle, but will not as flatten out as much as the Stiletto.)

[RichM 0]

Imho, there isn't any such thing as a canopy that will stay in the dive, just different radiuses of recovery. The way I figure it, this could only happen if the canopy produces exactly the same drag as the skydiver for nil recovery arc, or less drag than the skydiver for negative recovery arc (in which case it wouldn't have a natural glide path but would try to fly straight at the ground all the time. But theres no way any current inflated canopy produces less drag than the suspended skydiver, so the pair acting as a system will return to natural dynamic stability where the skydiver is suspended under the lift point of the canopy.

Just my 2c

Rich M

[hookit 0]

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I have seen a Xaos drop 1200ft on a 90degree riser to final and believe it could have continued to dive further.

I fly a Xaos loaded at 2.0 and I have never come close to losing 1200 feet on a 90 degree turn of any kind. I'd be curious to know the wing-loading, the aggressiveness of the turn and the altitude of the dz at which it was done if possible.

Thanks and Blue Skies!
-Trey

[Samurai136 0]

Perhaps that sounds too dramatic. According to the pilot he intiated the turn at 1200' and didn't seem to go too deep into the corner. I believe he was jumping an 84 or 87 sq ft Xaos. I don't know his name but it was after an NSL competition at SD Iowa this summer.

Ken

"Buttons aren't toys." - Trillian
Ken

[freeflir29 0]

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Could somebody who hasn't broken their tail trying to land a 1:1 loading, and does fly high performance canopies regularly, please interject here

Yeah..as you can see from Hooknswoop's post I OBVIOUSLY have no fucking clue what I am talking about. Sorry you don't know what a "Normal flight envelope" is. I suggest you start doing some reading if you plan on flying HP canopies.

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the canopy will only surge as you described if brakes are used and released.

Nope......did exactly that on my Stilletto one day. Hit some turbulence over the taxi way and couldn't hold the riser down any longer. I knew I was too high but figured Oh well so I don't swoop this time. With absolutely no further input after the front riser. I came to almsot a complete stop. Hanging in the air about 10-12 ft up. My first thought was Oh shit. Put in some brakes to keep it from surging forward and did a nice PLF since I was dropping almost straight down. I promise...a Stilletto WILL recover that hard.

[RichM 0]

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Nope......did exactly that on my Stilletto one day. Hit some turbulence over the taxi way and couldn't hold the riser down any longer. I knew I was too high but figured Oh well so I don't swoop this time. With absolutely no further input after the front riser. I came to almsot a complete stop. Hanging in the air about 10-12 ft up. My first thought was Oh shit. Put in some brakes to keep it from surging forward and did a nice PLF since I was dropping almost straight down. I promise...a Stilletto WILL recover that hard.

We have a slightly unhinged NZ instructor here at Headcorn, really nice bloke but completely off his trolley. 2 weeks ago he was in an accuracy competition under a stilletto, but he wasn't swooping, he was bringing it in on full brakes and shuffling it down to the pad (wingloading unknown, canopy is 120, guess his weight 12 stone or more). He has 6000+ jumps and really knows his canopy! This is not recommended behaviour, hehe.

Rich M