Does Front riser pressure get less with higher WL?

[Viking 0]

Ok here are the conditions.

Three Sizes mains 170 150 135 Would the same jumper weighting the same amount doing the same 90 degree turn get less front riser pressure with the different sizes/wl Or is wl what changes the pressure?

I swear you must have footprints on the back of your helmet - chicagoskydiver
My God has a bigger dick than your god -George Carlin

[Swooopa-x 0]

On a massive student canopy you could prob do pull ups on the frnts so maybe there is a size/pressure relationship there -but- nothing scales perfectly in aero design so I'm not sure you can break it down quite so simply.
My fx 93 has radically higher front riser pressure than my 105 hurricane .
My 105 actually felt to me like it had more pressure than my hurricane 120 (although that was a while back so ).
the designers could go nuts here I'm sure- line trim ; fabric used ; Line length ;
On a practical level - What are you trying to understand.

People dont care how much you know until they know how much you care.

[Viking 0]

I'm trying to understand if I should expect a lighter pressure with smaller canopys (no not even thinking of downsizing)

I'm just now starting to mess with my fronts on 190-210 size mains and after a 90 degree turn i can actually pick myself up out of the harness.

I swear you must have footprints on the back of your helmet - chicagoskydiver
My God has a bigger dick than your god -George Carlin

[Scoop 0]

Quote

On a massive student canopy you could prob do pull ups on the frnts so maybe there is a size/pressure relationship there

Haha, your right. In our student rigs with a Manta 280 I can pull my self up on the front risers to slide my leg straps down my legs a bit so I sit rather than dangle.

[Swooopa-x 0]

You can definitely expect a lighter press then yeah. Until x-braced - then it can be really heavy.
What's your loading btw?

People dont care how much you know until they know how much you care.

[Widgeon 0]

It depends on the canopy design. Something with a steep trim and line configuration that puts you out under the nose at full flight will just get heavier as the WL goes up.(Such as the Crossfire1) Demo everything you can.

You CAN swoop a 190 at your wingloading. Scott Miller can prove that.

[dharma1976 0]

Quote

Ok here are the conditions.

Three Sizes mains 170 150 135 Would the same jumper weighting the same amount doing the same 90 degree turn get less front riser pressure with the different sizes/wl Or is wl what changes the pressure?

Riser pressure gets less with better technique...

when I first got on my 129 Crossfire2 I was like damn the riser pressure gets crazy...then my technique got better adding harness and whatnot and it got better...

Cheers

Dave

http://www.skyjunky.com

CSpenceFLY - I can't believe the number of people willing to bet their life on someone else doing the right thing.

[superstu 0]

yes, WL effect riser pressure, but so does canopy size. if one was to add some weight and then try the 190 you'll see an increase in riser pressure. however, if you downsize you'll also be pulling less fabric, meaning most likely less front riser pressure.

I would say expect less front riser pressure if you're staying with the same parachute but smaller.

[dharma1976 0]

Quote

I would say expect less front riser pressure if you're staying with the same parachute but smaller.

hmmm dependant on a few more things...

for instance I flew a Crossfire2 149, riser pressure was light as hell...then i flew a 129 Crossfire2 Riser pressure was much greater...

until I learned how to use my harness :-P

Dave

http://www.skyjunky.com

CSpenceFLY - I can't believe the number of people willing to bet their life on someone else doing the right thing.

[ryoder 1,387]

In level flight, the sum of the pressures on your risers must always equal your weight. The size of the canopy is completely irrelevant. If one canopy has a lower front riser pressure than another, then it must also have higher rear riser pressure.

In a turn, the lateral accelleration is added to the riser pressures, which produces the G-force you feel in the saddle. The tighter the turn, (and the higher the airspeed), the higher the G-forces. Since the smaller canopy will have a higher airspeed, it will have higher riser pressure through a turn of the same radius.

"There are only three things of value: younger women, faster airplanes, and bigger crocodiles" - Arthur Jones.

[JumpRu 14]

there are exceptions:
jumped KA 120,107 and 97 from all 3 - 120 had lightest front riser pressure :)

[superstu 0]

i guess my statment was geared more specifically to the original poster and his particular instance of going from a 190, 170, 150.

I too notice that going from a vx 89 at 2.1 to a vx 84 at 2.2 there is substantial increase in riser pressure. and even more so going from a 2.2WL on my vx 84 to a 2.4+WL on the same vx84, at 2.4 my vx 84 is a different animal than at 2.2

i think speed is the major determinate of riser pressure. that's why some people start in deep brakes before a turn, they're "depressurizing" the canopy enough so they can pull on the fronts. try pulling your fronts down after you've started a turn, it's very difficult or even impossible on some canopies. why? because of the speed.

Slip Stream Air Sports
Do not go softly, do not go quietly, never back down

[Viking 0]

Quote

You CAN swoop a 190 at your wingloading. Scott Miller can prove that.

oh i know i can. yesterday i was flying a rental Safire2 209 (my usual sabre 190 was in a rig that wouldn't fit me) I landed in no wind and got a nice little surf out of it with just a straight in approach. On the next one I pulled double fronts up high on final and got an even better one.

I plan ring the crap out of my 190 when i finally buy my own.

Oh and my wingloading is 1.15ish depending on what i'v had to eat lol

I swear you must have footprints on the back of your helmet - chicagoskydiver
My God has a bigger dick than your god -George Carlin

[headoverheels 291]

Quote

In level flight, the sum of the pressures on your risers must always equal your weight. The size of the canopy is completely irrelevant. If one canopy has a lower front riser pressure than another, then it must also have higher rear riser pressure.

Speaking out of my hat, I don't think that this is necessarily true across canopy types. My Katana has lighter front riser force than my Nitron, without having higher rear riser force. Still speaking out of my hat, I think this is because the Katana leading edge, trim, etc. is designed so that it has less lift (for a given speed) as you pull the front risers down, which decreases force. Obviously, the force is being shifted to the rear risers, but nobody pulls down on front and rears simultaneously. Some aircraft have aileron designs that similarly decrease the required turning effort.

[marks 0]

Quote

but nobody pulls down on front and rears simultaneously.

try doing that, but opposite front than rear, pull them at the same time while you watch the canopy. if it doesnt do somthin cool, then pull your opposite toggle than front riser at same time.

edit to add:

make sure there is nobody, near you, or above you. or especially below you before you try this.

[SkymonkeyONE 3]

Uh, that's called "warping" and CRW guys do it all the time, Mark.

[justinb138 0]

Quote

Uh, that's called "warping" and CRW guys do it all the time, Mark.

What happens when you do it on a high-aspect ratio 9 cell though?

[marks 0]

Quote

Quote

Uh, that's called "warping" and CRW guys do it all the time, Mark.

What happens when you do it on a high-aspect ratio 9 cell though?

try it, you will see.

i think i've heard it called a helicopter before.

[rcc 0]

Mark one thing why would you tell someone that has 105 jumps to do helicopters.Why would he even be worried about front risers and harness turns he should be focusing on landing patterns and canopy coaching right now before the big things like swooping.

[1234hutch 0]

Ah
many thanks

I will ponder this

[Widgeon 0]

Quote

i think i've heard it called a helicopter before.

Use all rears.
Bring it to the edge of a stall, wait....... kick in the direction you want to spin and snatch one rear down and let the other up. You'll 'helicopter' alright.

[rcc 0]

(WRONG)
You want to be straight in your harness.If you kick the way you want to turn all you are doing is putting your self in bad line twist and spinning on your back very bad idea.

[Viking 0]

dude i'm pretty sure everyone saw he was just kidding around.

I swear you must have footprints on the back of your helmet - chicagoskydiver
My God has a bigger dick than your god -George Carlin

[Canuck 0]

Quote

Quote

Quote

Uh, that's called "warping" and CRW guys do it all the time, Mark.

What happens when you do it on a high-aspect ratio 9 cell though?

try it, you will see.

i think i've heard it called a helicopter before.

Nah, doesn't do anything like that at all. The sequential team I do video for sometimes call it "cross-control". I've done it on my Stiletto 107 loaded in the 1.9 range a few times to help stay behind them - no helicopter. Never tried it on my Velo, but I suspect it would be no different.

Canuck

[marks 0]

so tell me, what does the 107 stiletto do then?