Crosswind landings

[reyno_gr 0]

Jumped last Saturday and (luckily) learnt a lesson without getting hurt.
Having exited and completed a successful 2 way I opened on a long spot well up wind of the DZ.
I knew getting back was going to be problematic so I flew back in half brakes with my body coiled uo to reduce drag.
The winds were approximately 16mph and with this tail wind I made good progress. During this down wind run back to the DZ I identified (and over flew) several alternate land out options.
I crossed the DZ upwind boundary at about 500 feet and commenced a flat turn into wind. After a 90 degree turn I realised I wasn't going to get into wind unless I continued turning a further 90 degrees. Not a safe option so I accepted the intevitable crosswind landing.
As it was gusty I prepared for a PLF and as the canopy got hit by a gust and tipped downwind (as I flared) I successfully executed a PLF and came out unscathed.
Now I learnt lots of lessons from this:
1. During freefall I should have identified my position over the DZ (enabling me an option to pull higher - although we were being followed out by a solo and a tandem)
2. I SHOULD have landed at one of my safe alternatives (off the DZ) but into wind
3. I sensibly didn't continue to turn (hook) to get into wind.
My question is two fold. Pulling higher wasn't my plan and given I was being followed out by other Skydivers would this be an acceptable option or is it better to stick to the plan and accept landing off?
Secondly as the canopy got tipped by a gust to one side on landing is there anyway of dealing with this? Clearly using the toggles will only induce a turn.
Any thoughts please?

[DrewEckhardt 0]

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I knew getting back was going to be problematic so I flew back in half brakes with my body coiled uo to reduce drag.

With a moderate tail wind you'll go farthest when you pull the brakes down as far as they'll go without your glide path getting steeper. Many modern skydiving canopies don't loose glide ratio until they're on the verge of stalling. So more brakes may have gotten you back.

With a faster tail wind the canopy's glide ratio is less relevant. Maintaining the minimum sink rate and staying in the wind longer will take you farther.

[Darius11 12]

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Secondly as the canopy got tipped by a gust to one side on landing is there anyway of dealing with this?

I am very new as you can see from my jump #. Here is a grain of salt.

But I have practiced a bunch of crosswind landings.
You can compensate with the toggles. For example if you are heading North and the wind is coming from the west. By bringing down your left toggle you can go straight and flare in the same way and have a great landing. Make sure you keep the same length difference as you flair so your canopy will go straight.

I'd rather be hated for who I am, than loved for who I am not." - Kurt Cobain

[jumperconway 0]

on crosswind landings you have to use more toggle input on the side into the wind to keep the wing level!

[pilotdave 0]

I don't jump a Xaos-27 79, but my Sabre2 flies level independent of wind direction.

Dave

[jumperconway 0]

I think aerodynamicaly that's impossible because the relative wind is coming from the side. The stronger the wind the more input is required. Flaring evenly, the crosswind input is going to turn your canopy towards the downwind side whether it's a 79' Xaos or a 150 Sabre 2. It's less noticable in full flight.

[councilman24 36]

Jumpers routinely talk about a gust of wind turning their canopy one way or another on landing. Almost invariably it's that THEY turned the canopy. What happens is that during and at the end of a flare, if things aren't real smooth, people tend to reach out to balance themselves. This is usually with the down wind arm as they are moved sideways. Since that arm has a toggle in it, the canopies turns and increases the movement in that direction.

Watch some of the newer (and older jumers) who end up having to run off to one side. See if their hands are level. IF NOT, they are turning the canopy. The canopy is still flying even after touch down. I get a kick watching jumper after jumper land and come in saying "did you see that gust!"

I'm old for my age.
Terry Urban
D-8631
FAA DPRE

[Reginald 0]

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I crossed the DZ upwind boundary at about 500 feet and commenced a flat turn into wind. After a 90 degree turn I realised I wasn't going to get into wind unless I continued turning a further 90 degrees. Not a safe option...wind
3. I sensibly didn't continue to turn (hook) to get into wind.

Good post. I’m glad it worked out okay.

There are a lot of things going on in your post but one stuck in my head.

I’m confused here. I can do a flat 180 turn while losing only about 50 feet of altitude. I only lose about 250 feet on a maximum toggle 180. At 500 feet a flat 180 should not be a problem, what was going on caused it to be one? Was your “flat” turn not a flat turn, was there traffic, etc.?

"We've been looking for the enemy for some time now. We've finally found him. We're surrounded. That simplifies things." CP

[jumperconway 0]

Watch how the pilot has to fly an otter in on a day with a strong crosswind. He will have to steer it into the crosswind to land. If you are driving at high speed on an open hiway with strong crosswinds an you will either steer with pressure into the crosswind or get blown off the road.

[Fast 0]

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I think aerodynamicaly that's impossible because the relative wind is coming from the side. The stronger the wind the more input is required. Flaring evenly, the crosswind input is going to turn your canopy towards the downwind side whether it's a 79' Xaos or a 150 Sabre 2. It's less noticable in full flight.

I don't see how that is possible. Wouldn't the wind have to be acting on the canopy differently at different parts to make it turn?


I envision this:

|                     ^   |

|                   ^     |

|                 ^       |

|               ^         |          N

|             ^           |         W+E

|           ^             |          S

|         ^               |

|       ^                 |                   

|     ^                   |         Canopy heading indicated by ^

|   ^                     |




WIND -->

Where the canopy is maintaining heading but crabbing across the landing area as the mass of air it is in drifts. In that case if you wanted to land due north with no drift to the east then you would have to have the canopy heading NW. If you are flying due north with a wind out of the west you should just crab to the east, but not actually change heading in that direction?


Anyone clarify this?


edit: You wouldn't have to maintain a turn (more toggle towards the NW) in the NW direction, just have the heading be NW as you come in on final.

~D
Where troubles melt like lemon drops Away above the chimney tops That's where you'll find me.
Swooping is taking one last poke at the bear before escaping it's cave - davelepka

[jumperconway 0]

to clarify;
If you want to land straight you must put NW input (more left toggle). In full flight you have more penetration, as you flare the crabing effect get's exaggerated hence making you go more east than full flight.

[larsrulz 0]

You're correct. The wind will not turn a wing, neither aircraft nor canopy. The problem is that if you wish to fly straight during a crosswind landing, then you'll have to turn into the wind some, so that you're canopy is pushed sideways the same amount it flies in the opposite direction. This is what an aircraft does when it lands on a runway during crosswinds. An airplane only has one strip to land on, so it must set up differently than a canopy. Now if a canopy pilot wishes to land in the peas, then he'll have to add a crosswind correction.

There are some different phenomenon occurring with an aircraft pilot. The primary of which is that both wings don't experience the same overall relative wind during a crosswind. This is due to the fact that the fuselage blocks the wind to the inside of one of the wings. This is why aileron deflection happens during crosswind take-offs and landings.

I got a strong urge to fly, but I got no where to fly to. -PF

[Hooknswoop 19]

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I think aerodynamicaly that's impossible because the relative wind is coming from the side.

Then you don't understand aerodynamics. If the relative wind was coming from anywhere but in front of you, the canopy would collapse. You do not need to pull the upwind toggle down farther to keep the canopy above you in a crosswind.

Derek

[reyno_gr 0]

I was at 500 feet crossing the boundary. I had to fly down wind some distance as the boundary comprises of trees and I wan't to avoid turbulance created by them.
Its difficult to estimate my height when I commenced the turn but I'm quite happy that the flat turn did not result in signifcant altitude loss.
If I'm reading these posts correctly I understand the flare should be a little more pronounced (i.e uneven) in favour of the UPWIND side. Have I got this right?

[larsrulz 0]

Now, we're talking about changing speeds, so you're correct. As the canopy slows down, the push from the crosswind doesn't change, so either you'll drift some with the wind or you'll have to give more toggel input to turn yourself more into the wind. But in no way is the wind turning your canopy.

I got a strong urge to fly, but I got no where to fly to. -PF

[BillyVance 34]

You can get farther in less altitude by riding rear risers, not brakes. Of course, hanging on rear risers require more arm strength and endurance. But you could pull down a few inches and hold for 5 - 10 seconds at a time, release slowly, rest, then repeat and still make it back in better shape than brakes.

Flat turns can be done safely at 100 feet AGL unless your canopy is an ultra-loaded elliptical or something. Going downwind, pull to half-brakes, then slowly let one up a few inches and you will turn into the opposite direction. After finishing the turn, you let up the other brake to match the other and if there is enough altitude, let them both up fully before flare time. If not, hold the brakes at 1/4 or so, then flare. You do not want to let them up to full flight too fast or you'll surge into the ground.

Good job with the PLF. I've had to PLF a few jumps myself.

"Mediocre people don't like high achievers, and high achievers don't like mediocre people." - SIX TIME National Champion coach Nick Saban

[Hooknswoop 19]

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Watch how the pilot has to fly an otter in on a day with a strong crosswind. He will have to steer it into the crosswind to land.

The pilot is not steering the aircraft intot he wind to keep the wings level, he is using the wing low (as opposed to the crabbing) method of crosswind landings. The aircraft does not require the pilot to steer into the wind to keep the wings level, he drops the wing and gives a bit of opposite rudder to counter the crosswind and allows the aircraft to fly a straight in approach down the runway center line in a crosswind. If the pilot did not drop the wind and put in some opposite rudder, the aircraft wouldn't roll over from the crosswind, it would drift downwind at the speed of the crosswind component.

Take a canopy control course or talk to a CFI and get some aerodynamics instruction. You do not understand basic aerodynamics like you should to fly a HP canopy.

Derek

[kallend 1,623]

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You're correct. The wind will not turn a wing, neither aircraft nor canopy. The problem is that if you wish to fly straight during a crosswind landing, then you'll have to turn into the wind some, so that you're canopy is pushed sideways the same amount it flies in the opposite direction. This is what an aircraft does when it lands on a runway during crosswinds. An airplane only has one strip to land on, so it must set up differently than a canopy. Now if a canopy pilot wishes to land in the peas, then he'll have to add a crosswind correction.

There are some different phenomenon occurring with an aircraft pilot. The primary of which is that both wings don't experience the same overall relative wind during a crosswind. This is due to the fact that the fuselage blocks the wind to the inside of one of the wings. This is why aileron deflection happens during crosswind take-offs and landings.

All of the arguments I've seen here apply to steady winds. Add in a little wind shear (involving change of direction) and things can get quite squirrely.

...

The only sure way to survive a canopy collision is not to have one.

[reyno_gr 0]

Jumperconway's post (written whilst I was typing most last response) suggests uneven, upwind, input is not required! So whats the consensus? Flare evenly or more upwind toggle input?

[Hooknswoop 19]

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As it was gusty I prepared for a PLF and as the canopy got hit by a gust and tipped downwind (as I flared) I successfully executed a PLF and came out unscathed.

That is the classic crosswind flare oops. As you flare you begin to realize you are drifting across the ground with the crosswind. You reach out with your downwind hand, a natural human reaction, causing the canopy to turn downwind. Jumpers blame a gust of wind when this happens. This is the opposite reaction necessary to land corretly in a crosswind. Adding in upwind toggle more than downwind toggle will flare turn the canopy into the wind, helping to counter the crosswind component and lean your body into the wind.

Derek

[Hooknswoop 19]

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All of the arguments I've seen here apply to steady winds. Add in a little wind shear (involving change of direction) and things can get quite squirrely.

Correct, wind gusts, shear, etc, and all bets are off. At that point the pilot must give whatever input is required to flare the canopy to stops it's descent and flare turn/flat turn the canopy into the crosswind component.

Derek

[larsrulz 0]

That totally depends on the type of landing you want. You seemed to believe that the canopy was turned by the wind (or one side tipped up), this clearly cannot be the case, unless you experienced a dirt devil or other non-symmetric turbulence.

If you want a landing which is perfectly straight down a line, then you'll have to increase your toggle input as your canopy slows down, this will be required in perfectly constant crosswind landing. Now, with a sabre 190 (I used to fly one at 1:1), you'll be pushed crosswind if you flare evenly, but it will hardly be anything you can't easily walk out. This may be best to stick with a constant flare until you are more comfortable with your canopy. Or get some canopy coaching to work on your crosswind landings.

I got a strong urge to fly, but I got no where to fly to. -PF

[pilotdave 0]

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If the pilot did not drop the wing and put in some opposite rudder, the aircraft wouldn't roll over from the crosswind, it would drift downwind at the speed of the crosswind component.

The important point here is that canopies are not capable of a sideslip because they lack a rudder. You can't fly a canopy with one "wing" low without turning. Roll and yaw are highly coupled.

Kallend is right that unsteady winds will do weird things, but I still don't think jumperconway's advice is generally correct. You can steer into the wind to crab a canopy, but you can't sideslip a canopy.

Dave

[Hooknswoop 19]

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The important point here is that canopies are not capable of a sideslip because they lack a rudder. You can't fly a canopy with one "wing" low without turning. Roll and yaw are highly coupled.

Right, but our 'landing gear' is much less sensitive to landing with a crab angle than an aircraft's is. But ya, a crosswind landing doesn't turn or roll an aircraft or canopy, it only adds drift over the ground.

Derek

[pilotdave 0]

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Right, but our 'landing gear' is much less sensitive to landing with a crab angle than an aircraft's is

Not mine!

Dave