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Question about coming back from a long spot

 


Deimian

Dec 7, 2012, 5:28 AM
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Question about coming back from a long spot Can't Post

So you have just open your canopy and realize that you are far away from your landing zone. Sometimes you can make it back with appropriate piloting. Those are skills that develop over time, with training, and specific things might be canopy dependent. I understand all that. My question now is:

Which way is more likely to take you back to your LZ? Unstow your brakes and hang on your back risers, hang on your back risers with the brakes still stowed, or leave the brakes stowed and use the risers just for steering and correct your heading, without pulling both of them permanently?

I guess that would be canopy dependent, but in general, what would be the way? Or maybe it is plainly a very stupid question?


(This post was edited by Deimian on Dec 7, 2012, 5:29 AM)


potatoman  (Student)

Dec 7, 2012, 5:48 AM
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Re: [Deimian] Question about coming back from a long spot [In reply to] Can't Post

Read my signature first....

Lets take it top winds and bottom winds are the same direction.

When you are flying downwind, very long spot, deep brakes. You will float more, and the wind will take you there. Not too deep, then you will drop, so keep the airfoil there.
If less long spot, why bother getting your arms tired. Stow the slider, legturn into the downwind, and there you go.

When upwind, in slow windspeed. Less than canopy speed to get penetration.
No brakes, full up. if you are moving forward enough, there you go. Long spot, you will probably just make it, or plan ahead for the outlanding.
When the wind is strong, and you need to get upwind. Lets say windspeed and toggle up speed is the same. Time to hang on to the front risers. It is the only way you will get penetration (relative to ground), to actually move you forward.


Premier skybytch  (D License)

Dec 7, 2012, 6:03 AM
Post #3 of 72 (4585 views)
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Re: [Deimian] Question about coming back from a long spot [In reply to] Can't Post

In reply to:
I guess that would be canopy dependent, but in general, what would be the way?

Not a stupid question! It's canopy and jumper dependent. Only way to figure out what works best for you and your canopy is to go play with it.

In the canopy course we teach, we have jumpers do a hop and pop exiting about 2 miles upwind of the spot. They then try both sitting in deep brakes and using rears and decide for themselves which gets them further back.

You can leave the brakes stowed if you're using rears, but don't forget to unstow them long before your hard deck (imho, easier to unstow them),


(This post was edited by skybytch on Dec 7, 2012, 6:03 AM)


davelepka  (D 21448)

Dec 7, 2012, 6:22 AM
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Re: [Deimian] Question about coming back from a long spot [In reply to] Can't Post

 
This is a complicated subject, so I'll just post a few thoughts -

-First off, most modern canopies have very shallow brake settings. These help with those nice, slow openings, but they don't keep you up there very long with the brakes stowed, so pretty much plan on unstowing your brakes in any case.

-If you are upwind of the DZ (with the wind at your back), the idea becomes staying in the air as long as possible. The tailwind is helping to move you back to the DZ, so the longer you are airborne, the further the wind will push you.

For this reason, deep brakes are typically the best option as they provide the lowest descent rate, and the longer it takes to get to the ground, the further the wind will push you. So get yourself turned toward the DZ, and get on the brakes ASAP to give yourself the best chance to make it home.

-If you are downwind of the DZ (with the wind blowing in your face), now you have another problem. What you're trying to do now is penetrate as far into the wind as possible, so what you're looking for is higher airspeed, so the best option is generally full flight.

To aid that, you can tuck your legs up by bending at the knee and getting your lower legs behind your upper leg, thus reducing drag. Keep your arms in tight to your body, and maybe even behind your body, again to reduce drag. All of these little steps will boost your forward speed by a couple %, and help get you that much further into the wind.

HOWEVER - with all that said, here's the important info - 'getting back' to the DZ does not mean coming 2 feet over the trees to take a downwinder on the edge of the field. Getting back means making it to the DZ with enough altitude to spare to still allow you to fly a normal landing pattern and land with the regular flow of traffic.

All of the tricks and tips above should be used in an attempt to get yourself back to the pattern enrty point above the DZ, not just back to the DZ. If you cannot make the pattern entry point, then you need to divert to an alternate LZ where you can fly a landing pattern, and just take the off field landing.

The way you do that is to take your current altitude, let's say 3000ft, then subtract the pattern entry altitude, let's say that's 800ft. So you have 2200ft of altitude to make it back to the landing pattern.

Now that you know that number, cut it in half and see how far you get after flying halfway down. So you'll float along for 1100ft, and if you're not halfway back to the landing pattern, you're probably not going to make the other half.

Of course, during this first half you should be scoping out alternate LZs along the way, so if you do find that you didn't make it halfway back, now you're at 1900ft and you have a good working knowledge of all the places you just overflew. Pick one and land there using a standard landing pattern.


klippetop  (C 2629)

Dec 7, 2012, 6:33 AM
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Re: [Deimian] Question about coming back from a long spot [In reply to] Can't Post

I've been taught, that in my big ass student canopy, when I give myself a bad spot and risk going backwards because of headwind, it's better to be at a 45 degree angle to the wind. The theory should be, that I present less canopy to the wind and by zigzagging with flat turns, I can cover more ground.

I havent done it enough times to know if it's actually working yet. Any comments from the canopy gurus? Do i burn too much altitude on the turns?

Frontriser on the student chute isnt really an option (im not heavy enough).


elightle  (D 5966)

Dec 7, 2012, 6:54 AM
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Re: [davelepka] Question about coming back from a long spot [In reply to] Can't Post

I am an old timer who started on round parachutes, so looking for alternate landing areas was a must! I don't use Dave's calculations, per se, but I monitor my altitude vs. how far I am from the DZ, and I always have a spot picked out in case I can't make it back.


wolfriverjoe  (A 50013)

Dec 7, 2012, 6:54 AM
Post #7 of 72 (4514 views)
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In reply to:
I've been taught, that in my big ass student canopy, when I give myself a bad spot and risk going backwards because of headwind, it's better to be at a 45 degree angle to the wind. The theory should be, that I present less canopy to the wind and by zigzagging with flat turns, I can cover more ground.

I havent done it enough times to know if it's actually working yet. Any comments from the canopy gurus? Do i burn too much altitude on the turns?

Frontriser on the student chute isnt really an option (im not heavy enough).

What?!?!? Crazy

Turning 45 to the wind will make you go sideways, and less forward.

You are in the air. You are part of the airmass. You can't "tack" like a sailboat because you have nothing to anchor you to the ground,


davelepka  (D 21448)

Dec 7, 2012, 7:11 AM
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Re: [elightle] Question about coming back from a long spot [In reply to] Can't Post

Quote:
I am an old timer who started on round parachutes, so looking for alternate landing areas was a must! I don't use Dave's calculations, per se, but I monitor my altitude vs. how far I am from the DZ

I was actually taught that by another old timer, who called it the 'halfway-down halfway-back' rule.

It's not an exact science, just an idea for how to come up with a 'best guess' if you're going to make it.


klippetop  (C 2629)

Dec 7, 2012, 7:56 AM
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Re: [wolfriverjoe] Question about coming back from a long spot [In reply to] Can't Post

I understand that i dont pick up speed like a boat by going a little angular to the wind. And 45 degrees might be overdoing it. But I think the idea is, that the wind "sees" a smaller area of the canopy by going at an angle. Therefore it pushes less. But yes, I do go sideways when doing it.

It might not work. Therefore the question here. ;) But the advice came from the instructor at a canopy course where all of us on underloaded 240'rigs flew backwards.


labrys  (D 29848)

Dec 7, 2012, 8:41 AM
Post #10 of 72 (4405 views)
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Quote:
But I think the idea is, that the wind "sees" a smaller area of the canopy by going at an angle. Therefore it pushes less. But yes, I do go sideways when doing it.

Put a piece of 8x11 paper with the long edge on top flat on a surface. Imagine the wind hitting it directly along the top edge. That's what the wind "sees", right?

Now turn the paper 30 degrees or so to the right and imagine the wind coming from the same direction. Can you see that the wind now "sees" more surface area and not less?


klippetop  (C 2629)

Dec 7, 2012, 8:53 AM
Post #11 of 72 (4398 views)
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Re: [labrys] Question about coming back from a long spot [In reply to] Can't Post

In reply to:
Quote:
But I think the idea is, that the wind "sees" a smaller area of the canopy by going at an angle. Therefore it pushes less. But yes, I do go sideways when doing it.

Can you see that the wind now "sees" more surface area and not less?

Damn. You're right. There goes that theory...


wolfriverjoe  (A 50013)

Dec 7, 2012, 8:57 AM
Post #12 of 72 (4393 views)
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In reply to:
I understand that i dont pick up speed like a boat by going a little angular to the wind. And 45 degrees might be overdoing it. But I think the idea is, that the wind "sees" a smaller area of the canopy by going at an angle. Therefore it pushes less. But yes, I do go sideways when doing it.

It might not work. Therefore the question here. ;) But the advice came from the instructor at a canopy course where all of us on underloaded 240'rigs flew backwards.

Number One, most important. I'm not ripping on you. This is a very common misconception. Probably second only to the 45 degree rule.
And the only way you learn things is to ask these kinds of questions.

The wind doesn't "see" anything. And it doesn't really "push" either.

You are in the airmass. You are moving along with it. Your airspeed in the air is completely independent of your ground speed. You can compare a boat in a river current to get the idea. Any speed the boat goes by powering the boat (motor or oars) will be relative to the water, not the shore. The speed relative to the shore will be a combination of the waterspeed and the current speed.

Think basic trig. If you have a headwind of 20 mph and a forward airspeed of 20 mph then your ground speed is zero. If you take a 45 degree angle, then your 20 mph forward airspeed is still there. But your groundspeed will be a function of the angles. Into the wind will now be 14 mph (or backwards 6) and sideways will be 14 (since it's perpendicular to the wind, it will be sideways 14).

Did these same instructors warn you about making sharp turns while travelling downwind because the tailwind might make your canopy collapse?


Deimian

Dec 7, 2012, 9:11 AM
Post #13 of 72 (4376 views)
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Re: [Deimian] Question about coming back from a long spot [In reply to] Can't Post

Wow, it looks like I've started an interesting debate. I'm glad I'm not the only one learning here.


mr2mk1g  (C 103449)

Dec 7, 2012, 9:12 AM
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Re: [Deimian] Question about coming back from a long spot [In reply to] Can't Post

Always always always pop the brakes. Follow your student drill - release brakes and control check. What you do after that depends but it should always be after popping the brakes.

Several people have died in recent years because they left the brakes stowed until finals... only to find a problem with their steering lines and as they were now way too low to cutaway and deploy their reserve they fought the problem to impact when it could have been solved or ditched after opening at 3,000ft.


Deimian

Dec 7, 2012, 9:25 AM
Post #15 of 72 (4359 views)
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In reply to:
Always always always pop the brakes. Follow your student drill - release brakes and control check. What you do after that depends but it should always be after popping the brakes.

Several people have died in recent years because they left the brakes stowed until finals... only to find a problem with their steering lines and as they were now way too low to cutaway and deploy their reserve they fought the problem to impact when it could have been solved or ditched after opening at 3,000ft.

Very good point, I didn't think about that, but makes perfectly sense.


popsjumper  (D 999999999)

Dec 7, 2012, 9:37 AM
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Re: [wolfriverjoe] Question about coming back from a long spot [In reply to] Can't Post

In reply to:
In reply to:
I understand that i dont pick up speed like a boat by going a little angular to the wind. And 45 degrees might be overdoing it. But I think the idea is, that the wind "sees" a smaller area of the canopy by going at an angle. Therefore it pushes less. But yes, I do go sideways when doing it.

It might not work. Therefore the question here. ;) But the advice came from the instructor at a canopy course where all of us on underloaded 240'rigs flew backwards.

Number One, most important. I'm not ripping on you. This is a very common misconception. Probably second only to the 45 degree rule.
And the only way you learn things is to ask these kinds of questions.

The wind doesn't "see" anything. And it doesn't really "push" either.

You are in the airmass. You are moving along with it. Your airspeed in the air is completely independent of your ground speed. You can compare a boat in a river current to get the idea. Any speed the boat goes by powering the boat (motor or oars) will be relative to the water, not the shore. The speed relative to the shore will be a combination of the waterspeed and the current speed.

Think basic trig. If you have a headwind of 20 mph and a forward airspeed of 20 mph then your ground speed is zero. If you take a 45 degree angle, then your 20 mph forward airspeed is still there. But your groundspeed will be a function of the angles. Into the wind will now be 14 mph (or backwards 6) and sideways will be 14 (since it's perpendicular to the wind, it will be sideways 14).

Did these same instructors warn you about making sharp turns while travelling downwind because the tailwind might make your canopy collapse?

Thanks for that. It's unbelievable how many people actually believe the wind "pushes" the canopy and I've had that conversation with many long-timers....several were AFFIs......unbelievale.


DocPop  (C License)

Dec 7, 2012, 9:38 AM
Post #17 of 72 (4343 views)
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Re: [labrys] Question about coming back from a long spot [In reply to] Can't Post

In reply to:
Quote:
But I think the idea is, that the wind "sees" a smaller area of the canopy by going at an angle. Therefore it pushes less. But yes, I do go sideways when doing it.

Put a piece of 8x11 paper with the long edge on top flat on a surface. Imagine the wind hitting it directly along the top edge. That's what the wind "sees", right?

Now turn the paper 30 degrees or so to the right and imagine the wind coming from the same direction. Can you see that the wind now "sees" more surface area and not less?

This is not realistic. The relative wind under canopy is always from the front (unless your feet are on the ground).


klippetop  (C 2629)

Dec 7, 2012, 9:40 AM
Post #18 of 72 (4332 views)
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Re: [wolfriverjoe] Question about coming back from a long spot [In reply to] Can't Post

In reply to:
In reply to:
I understand that i dont pick up speed like a boat by going a little angular to the wind. And 45 degrees might be overdoing it. But I think the idea is, that the wind "sees" a smaller area of the canopy by going at an angle. Therefore it pushes less. But yes, I do go sideways when doing it.

It might not work. Therefore the question here. ;) But the advice came from the instructor at a canopy course where all of us on underloaded 240'rigs flew backwards.

Number One, most important. I'm not ripping on you. This is a very common misconception. Probably second only to the 45 degree rule.
And the only way you learn things is to ask these kinds of questions.

The wind doesn't "see" anything. And it doesn't really "push" either.

You are in the airmass. You are moving along with it. Your airspeed in the air is completely independent of your ground speed. You can compare a boat in a river current to get the idea. Any speed the boat goes by powering the boat (motor or oars) will be relative to the water, not the shore. The speed relative to the shore will be a combination of the waterspeed and the current speed.

Think basic trig. If you have a headwind of 20 mph and a forward airspeed of 20 mph then your ground speed is zero. If you take a 45 degree angle, then your 20 mph forward airspeed is still there. But your groundspeed will be a function of the angles. Into the wind will now be 14 mph (or backwards 6) and sideways will be 14 (since it's perpendicular to the wind, it will be sideways 14).

Did these same instructors warn you about making sharp turns while travelling downwind because the tailwind might make your canopy collapse?

Yeah, I'm convinced. Gonna try to find a decent way to point it out to the instructor maybe or just ask him again.

So im back to trying to be small with my arms and legs directly against the wind. Thx for the feedback..

Havent heard about the no sharpies in downwind either.


DocPop  (C License)

Dec 7, 2012, 9:40 AM
Post #19 of 72 (4331 views)
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Re: [davelepka] Question about coming back from a long spot [In reply to] Can't Post

In reply to:
-If you are upwind of the DZ (with the wind at your back), the idea becomes staying in the air as long as possible. The tailwind is helping to move you back to the DZ, so the longer you are airborne, the further the wind will push you.

For this reason, deep brakes are typically the best option as they provide the lowest descent rate, and the longer it takes to get to the ground, the further the wind will push you. So get yourself turned toward the DZ, and get on the brakes ASAP to give yourself the best chance to make it home.

-If you are downwind of the DZ (with the wind blowing in your face), now you have another problem. What you're trying to do now is penetrate as far into the wind as possible, so what you're looking for is higher airspeed, so the best option is generally full flight.

To aid that, you can tuck your legs up by bending at the knee and getting your lower legs behind your upper leg, thus reducing drag. Keep your arms in tight to your body, and maybe even behind your body, again to reduce drag. All of these little steps will boost your forward speed by a couple %, and help get you that much further into the wind.

To add to what Dave said - you should also make yourself small if you are upwind - it will still improve your glide ratio.


klippetop  (C 2629)

Dec 7, 2012, 9:46 AM
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Re: [DocPop] Question about coming back from a long spot [In reply to] Can't Post

In reply to:
In reply to:
-If you are upwind of the DZ (with the wind at your back), the idea becomes staying in the air as long as possible. The tailwind is helping to move you back to the DZ, so the longer you are airborne, the further the wind will push you.

For this reason, deep brakes are typically the best option as they provide the lowest descent rate, and the longer it takes to get to the ground, the further the wind will push you. So get yourself turned toward the DZ, and get on the brakes ASAP to give yourself the best chance to make it home.

-If you are downwind of the DZ (with the wind blowing in your face), now you have another problem. What you're trying to do now is penetrate as far into the wind as possible, so what you're looking for is higher airspeed, so the best option is generally full flight.

To aid that, you can tuck your legs up by bending at the knee and getting your lower legs behind your upper leg, thus reducing drag. Keep your arms in tight to your body, and maybe even behind your body, again to reduce drag. All of these little steps will boost your forward speed by a couple %, and help get you that much further into the wind.

To add to what Dave said - you should also make yourself small if you are upwind - it will still improve your glide ratio.

Hypothetically, if windspeed is faster than canopy speed (so youre feeling the relative wind on your back). Wouldnt you want to make yourself big? I know that this is more rare than you going faster than the wind.


wolfriverjoe  (A 50013)

Dec 7, 2012, 9:57 AM
Post #21 of 72 (4311 views)
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Re: [klippetop] Question about coming back from a long spot [In reply to] Can't Post

In reply to:
Hypothetically, if windspeed is faster than canopy speed (so youre feeling the relative wind on your back). Wouldnt you want to make yourself big? I know that this is more rare than you going faster than the wind.

How would you feel the realtive wind on your back? Aren't you still going forward through the air?

If you could feel the wind at your back, the canopy would stall.

Let me ask this: Would it help a hot air balloon to deploy some sort of sail? Would this affect it's ground speed at all?


StreetScooby

Dec 7, 2012, 10:02 AM
Post #22 of 72 (4302 views)
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Re: [Deimian] Question about coming back from a long spot [In reply to] Can't Post

Another thing to consider that's not related directly to your canopy. When I'm long on a spot, I find the nearest road and ride it. You'll get a thermal that will keep you up longer, even at 3K'.

Keep in mind when picking a off-DZ spot to land - there are power lines next to most roads, and you might not see them until you're low. Also, when landing in fields, keep an eye out for barbed wire fences. They're very difficult to see until you're right on them, and they will ruin your day. Try and notice any separation lines in fields, as that will most likely be where you'll find a fence. Don't wait too long to pick your spot landing off DZ. Also, get a feel for the wind direction somehow before choosing your landing direction. Blowing grass is a good indicator.


(This post was edited by StreetScooby on Dec 7, 2012, 10:03 AM)


klippetop  (C 2629)

Dec 7, 2012, 10:21 AM
Post #23 of 72 (4276 views)
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Re: [wolfriverjoe] Question about coming back from a long spot [In reply to] Can't Post

In reply to:
Aren't you still going forward through the air?

If you could feel the wind at your back, the canopy would stall.

Doh. Was thinking that if my groundspeed was lower than actual windspeed. But Im still going relative to the wind so I will always feel the wind against my face. And yes, I see that would stall the canopy..

In reply to:
Let me ask this: Would it help a hot air balloon to deploy some sort of sail? Would this affect it's ground speed at all?

Dont know actually. Wouldnt it move faster? My extremely limited knowledge about hot air balloons says that they cant steer and only move with the wind. Wouldnt a larger area then mean more speed? Or is the balloon always travelling at the same speed as the wind around it?


wolfriverjoe  (A 50013)

Dec 7, 2012, 10:29 AM
Post #24 of 72 (4268 views)
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Re: [klippetop] Question about coming back from a long spot [In reply to] Can't Post

In reply to:
In reply to:
Aren't you still going forward through the air?

If you could feel the wind at your back, the canopy would stall.

Doh. Was thinking that if my groundspeed was lower than actual windspeed. But Im still going relative to the wind so I will always feel the wind against my face. And yes, I see that would stall the canopy..

In reply to:
Let me ask this: Would it help a hot air balloon to deploy some sort of sail? Would this affect it's ground speed at all?

Dont know actually. Wouldnt it move faster? My extremely limited knowledge about hot air balloons says that they cant steer and only move with the wind. Wouldnt a larger area then mean more speed? Or is the balloon always travelling at the same speed as the wind around it?

A balloon has zero airspeed. It is always moving with the wind (presumung a steady-state wind). All that would happen if you put out a sail is that the sail would hang there, motionless.

And don't worry about the "Doh." Being willing to admit that you don't know, or that what you think about something is not correct is the foundation of learning.

Like I said in post 12, this is an area that is very, very often misunderstood. Pops mentioned that there are AFFIs out there that don't get it.


airtwardo  (D License)

Dec 7, 2012, 10:30 AM
Post #25 of 72 (4268 views)
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Re: [StreetScooby] Question about coming back from a long spot [In reply to] Can't Post

In reply to:
Another thing to consider that's not related directly to your canopy. When I'm long on a spot, I find the nearest road and ride it. You'll get a thermal that will keep you up longer, even at 3K'.

Keep in mind when picking a off-DZ spot to land - there are power lines next to most roads, and you might not see them until you're low. Also, when landing in fields, keep an eye out for barbed wire fences. They're very difficult to see until you're right on them, and they will ruin your day. Try and notice any separation lines in fields, as that will most likely be where you'll find a fence. Don't wait too long to pick your spot landing off DZ. Also, get a feel for the wind direction somehow before choosing your landing direction. Blowing grass is a good indicator.

~That thermal thing may work on a hot no wind day, but if there is a cross wind of any significance at all it dissipates the thermal off & away from the surface creating it... you can still find some of it if you're good, but I seriously doubt it at 3K.

THAT being said, nothing wrong with heading for a road when you see you won't make it back...it makes it easier for someone at the DZ to snag you when you land, it keeps you off farmer Mcnastys crops, cows & meth lab...and though as you said there may be power-lines etc to be wary of 'other than that' - the area next to most roads are relative free of obstacles.

To reiterate a point made above...release the brakes on opening and do the control check 1st, finding yourself in or near the pattern is a really bad time & place to figure out you have a control line problem.

It's simple enough to put the released toggle over the fingers and then grab the risers with your hand to hold the brakes on without getting tired.

~you should know the 'basic' wind direction prior to boarding the aircraft...look at the windsock & face into the wind - note where the sun is in relation to your body position.
In 'most' cases that will remain the same for the time of the jump. (yeah yeah I know what about at noonSly)...look for other indicators, smoke, flags, trees blowing, how the canopy tracks...

Keep your eyes open for clean landing spots if you are long...it MAY be better for you to hold all the way down to insure an uneventful landing with a long walk than it is to take a shot at making over that forest with the huge pond full of alligators!


(This post was edited by airtwardo on Dec 7, 2012, 10:41 AM)


dthames  (B 37674)

Dec 7, 2012, 10:30 AM
Post #26 of 72 (1872 views)
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Re: [Deimian] Question about coming back from a long spot [In reply to] Can't Post

The USPA Canopy Control Proficiency Card has a jump where you return from a long spot. I was instructed to take the spot about 1 mile beyond what was normal, to open at normal altitude (inflated about 3,000), and then work with the brakes and the risers to figure out the best way to make it back.

I tried hanging on the brakes for a while and determined how much good that did me. Then I got on the rear risers and tried to see how they would work. I stayed with the rear risers until I got back to the edge of the field, just under 1000 feet. I learned a lot and it was a great challenge.

I got a chuckle out of it because I was told that some of the jumpers that didnt know what I was up to saw me low and far away. Someone remarked about the bad spotand then I made it back thanks to my poofy Pilot and a bit of a tail wind.


DocPop  (C License)

Dec 7, 2012, 10:43 AM
Post #27 of 72 (1862 views)
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Re: [klippetop] Question about coming back from a long spot [In reply to] Can't Post

In reply to:

Hypothetically, if windspeed is faster than canopy speed (so youre feeling the relative wind on your back). Wouldnt you want to make yourself big? I know that this is more rare than you going faster than the wind.

This won't happen. To feel the relative wind on your back, you would have to be flying backwards. Forget about windspeed (which is measured relative to the ground) - your canopy is designed to fly with forward airspeed which is how it stays inflated and creates lift.

ETA: I saw that you subsequently worked this out yourself. Good stuff! This is important knowledge to have - and not everyone does!


(This post was edited by DocPop on Dec 7, 2012, 10:46 AM)


wolfriverjoe  (A 50013)

Dec 7, 2012, 10:50 AM
Post #28 of 72 (1851 views)
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Re: [airtwardo] Question about coming back from a long spot [In reply to] Can't Post

In reply to:
THAT being said, nothing wrong with heading for a road when you see you won't make it back...it makes it easrier for someone at the DZ to snag you when you land, it keeps you off farmer Mcnastys crops, cows & meth lab...and though as you said there may be power-lines etc to be wary of 'other than that' - the area next to most roads are relative free of obstacles.

Wow. It's pretty rare that I disagree with you, but I certainly do here.

Roads usually have powerlines, ditches, fences, mailboxes, culverts (driveways that go over the ditch), not to mention cars. They are a bad place to try and land anywhere near (the cars and especially big trucks push a lot of air when they go past, nasty turbulence).

I was taught to avoid any straight lines. Field edges, road sides, even boundaries between two fields. They often have the above mentioned obstacles.

The ideal off landing area is a hayfield or empty pasture. Right in the middle.
Uncultivated fields are also good, but beware the furrows, I've known ankles to be broken landing in a plowed field.

Cultivated fields aren't the best. The farmers tend to get annoyed when their livelyhood gets damaged (we used to have a "field fund" - out landers tossed a buck in each time, the money was given to the farmer at the end of the year). And landing in crops has it's hazards. Beans grab ankles, wheat can make height judgement difficult and corn...

Hurts.

Occupied pastures are bad news too. Aside from "landmines", you don't know the temperament of the "occupants." Horses tend to spook, cows tend to be curious, and if it's a big open field with only one occupant, don't land there (think about why he's alone and that it might be because he doesn't get along with others well).

It's not that hard to pick good "out landing" areas. In a 182 there's plenty of time to look around and see what's open, and what's in it. Spotting the different types of fields from the air takes a bit of practice, but anyone who's jumped for a while can help pick stuff out. Or you can try to guess what's in each field near a road, and then go see if you were right.


airtwardo  (D License)

Dec 7, 2012, 11:18 AM
Post #29 of 72 (1839 views)
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Re: [wolfriverjoe] Question about coming back from a long spot [In reply to] Can't Post

The ideal off landing area is a hayfield or empty pasture. Right in the middle.
Uncultivated fields are also good, but beware the furrows, I've known ankles to be broken landing in a plowed field.

In reply to:

Indeed it is, I guess I should have made that point clearer instead of just saying a 'clean' area...

As far as roads & straight lines...sure there is some logic to that, one needs to be aware of what to look for and hopefully you're facing into the wind on landing and can select an open spot that may be 'along those lines' so to speak.

Keep in mind the 'avoid straight lines' doctrine is a hold-over from the round parachute days which of course had a lot less control & accuracy...yes it still has some validity but not as much as in days gone by. Again that 'circle of safety' needed was a LOT bigger then.

Going full bore downwind with the idea of hooking a 180 into the wind at the last possible second in order to save some steps walkin' back is a really poor approach.

Understand you're in a bad 'unusual' situation and plan a normal pattern accordingly...if you are at say 500' facing into the wind and can't see & avoid power-lines or fence-lines ~ Darwin kinda wins!

It's a judgement call I guess, one needs to be realistic about their canopy control abilities and accuracy skills.

You're not landing a fighter at 200 kts, your circle of safety regarding the place & amount of clear area you need should be well established in your mind while on downwind...if you 'need' a football field to feel comfortable, by all means head to the planted field...if you know you can land standing up between parked cars in a Waly-mart parking lot (cough cough) it opens up the possible safe zone quite a bit.

High trees & water scare me more than power lines...the lines usually are 'avoidable' with steering input on base & final...not always the case with trees & water if they cover a big enough area.

It's situational specific obviously, another reason to try to be aware of your surroundings...a highway vs. a farmers field access road have significant differences regarding possible obstacles.

If you can't see & avoid a mailbox or light pole, a with a square parachute from 200'...ummm, ya should really get to working on either that or how to pick up a 7-10 split for a spare!
Sly


(This post was edited by airtwardo on Dec 7, 2012, 11:49 AM)


klippetop  (C 2629)

Dec 7, 2012, 11:45 AM
Post #30 of 72 (1818 views)
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Re: [wolfriverjoe] Question about coming back from a long spot [In reply to] Can't Post

Thx for the feedback. I'm pretty sure, i'm not the only rookie who could learn something from this thread. But I like learning the mechanichs of canopy flight..


pchapman  (D 1014)

Dec 7, 2012, 12:12 PM
Post #31 of 72 (1806 views)
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Re: [wolfriverjoe] Question about coming back from a long spot [In reply to] Can't Post

[EDIT: Looks like Twardo has made the point already but anyway:]

There is actually a happy medium in the debate on "go for a road" vs. "go for a field":

I say, go for near a road, but not right next to it, and only to the limitation of your own skill.

Some people make a beeline back towards the DZ and when they can't make it, end up in the middle of some muddy or crop filled field. Better to make the decision early and head for someplace safe but easier to get home from on the ground, like near an access road.

If you don't want to deal with gravel or pavement on roads, telephone and power wires, ditches, fences, etc, then land a short ways into the neighbouring field -- 50 m, 100m, whatever is in your comfort zone based on the conditions.

Personally I've swooped under a wire stretched across a road and then run the landing off into a ditch at dusk, so as not to spook an oncoming car too much -- but that doesn't mean that's the normal smart thing to do...

So "go for a road" should be interpreted as "near a road but a safe distance away from related obstacles".

(And wolfriver, thanks for countering the "wind at one's back" misconception!)


(This post was edited by pchapman on Dec 7, 2012, 12:14 PM)


linebckr83  (D 30571)

Dec 7, 2012, 12:12 PM
Post #32 of 72 (1805 views)
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Re: [klippetop] Question about coming back from a long spot [In reply to] Can't Post

This is the way it was described to me:

Imagine that you are in a giant blimp. So giant that you can fly a parachute inside of it. Say this blimp is moving forward at 100mph. Inside of it, you are flying your parachute around with a forward speed of 20mph.

If you are flying your canopy in the same direction as the blimp is flying, does your canopy "see" 120mph of air or only 20? If you turn around and fly the opposite direction, will you feel 80mph of wind on your back? The answer of course is no.

The blimp represents an air mass. Wind is simply a measure of the motion of this air mass in relation to the ground. So if you are flying your canopy in wind, you are flying around inside of this moving air mass just like the blimp example. The only affect it will have is in relation to the ground. Your parachute will "see" the same speed of air moving over it regardless of how the air mass is moving.

So if you are upwind on a long spot, you are in an air mass moving towards your target, and you want to stay off the ground until you get to this target. Like others said, generally your best bet is to ride in deep brakes and essentially "float" and let the air mass carry you to your target.

If you are downwind on a long spot, you are in an air mass moving away from your target. Obviously in this case you do not want to simply "float" as the air mass will just carry you further away. You need as much forward speed as possible to overcome the air mass's opposite motion and get to your target. Your best bet is to get in full flight and possibly use front risers, but people tend to debate on that part.

In either case, you want to move forward in the air mass as much as possible. How do you go forward more? You speed up. How do you speed up? You get rid of what is slowing you down (reduce drag). The best way to do this is get small. Pull legs up, tuck arms in. Your drag is reduced and your forward speed increases. This helps in either case, whether you're floating in the air mass or fighting it.

Many people think if they are upwind they can "get big" and use the wind to push them back. But refer back to the blimp example. If the same blimp is flying 100mph forward, and you are inside it flying 20mph normally, you have 120mph speed in relation to the ground. Say you get as big as possible. What changed? You just increased your drag, and your canopy speed reduces to 18mph. Now you are traveling at 118mph. You are hurting your chance at getting back. If you get small and begin flying at 22mph, your speed over the ground is now 122mph.

So remember...the wind is what it is. It's a moving air mass and you have no control over that. What you can control is your own speed while in this air mass, and amount of time inside it.

For the future in case you don't know the difference between groundspeed and airspeed. In the blimp example, your airspeed is 20mph. It is the physical flow over and around your airfoil. Your ground speed would be 120mph, and it is your speed in relation to the ground. So basically a sum of all things affecting your speed over the ground. Very different things and its an important concept to understand in regards to flying canopies.


Premier billvon  (D 16479)
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Dec 7, 2012, 12:51 PM
Post #33 of 72 (1790 views)
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Re: [Deimian] Question about coming back from a long spot [In reply to] Can't Post

Some tricks:

1) Get your drag as low as possible. Take off booties or keep them oriented into the wind. Unzip wingsuits as much as possible. Take off swoop cords if so equipped. Kill slider and bring it down if possible.

2) Let the canopy spread out. Loosen your chest strap if safe to do so and get the slider down as low as possible.

3) Try spreading your rear risers to improve your glide ratio a bit. It flattens your canopy a little and pulls the center of the tail down a little.

4) Flying into the wind the above tricks work pretty well. Flying downwind going to brakes works well. The trick is to stay in the air as long as possible so the wind helps you for as long as possible. Keeping brakes stowed might be an option. NOTE - if you do this make sure you unstow them before you get to your decision altitude, so if you discover a stuck/broken brake line you can deal with it.

5) In no wind you can experiment with brakes. For most canopies, a little bit of brake gives you a better glide than using rear risers.


Quagmirian  (A 110392)

Dec 7, 2012, 1:02 PM
Post #34 of 72 (1779 views)
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Re: [billvon] Question about coming back from a long spot [In reply to] Can't Post

In reply to:
For most canopies, a little bit of brake gives you a better glide than using rear risers.
Does this actually improve absolute glide ratio, ie would you cover more ground in still air?


airtwardo  (D License)

Dec 7, 2012, 1:36 PM
Post #35 of 72 (1765 views)
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Re: [Quagmirian] Question about coming back from a long spot [In reply to] Can't Post

In reply to:
In reply to:
For most canopies, a little bit of brake gives you a better glide than using rear risers.
Does this actually improve absolute glide ratio, ie would you cover more ground in still air?

It's hard to say it absolutely will with all canopies, it's dependent on the wing and the loading etc. It usually does...when ya find the sweet spot & you are in the air longer with a minimal loss of forward speed you go father.

It's that you're trading more time under canopy for forward speed...with a tailwind you tend to cover a lot more ground that way, not always necessarily so in 'still' air depending on the trim etc.


(This post was edited by airtwardo on Dec 7, 2012, 1:55 PM)


DocPop  (C License)

Dec 7, 2012, 1:57 PM
Post #36 of 72 (1761 views)
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Re: [Quagmirian] Question about coming back from a long spot [In reply to] Can't Post

In reply to:
In reply to:
For most canopies, a little bit of brake gives you a better glide than using rear risers.
Does this actually improve absolute glide ratio, ie would you cover more ground in still air?

I am not so sure about that. Brakes add drag, using a touch of rears will improve the glide path without adding to the drag.

Of course this may be offset by the fact that holding rears for a long time is hard work.


labrys  (D 29848)

Dec 7, 2012, 2:02 PM
Post #37 of 72 (1758 views)
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Re: [DocPop] Question about coming back from a long spot [In reply to] Can't Post

Quote:
This is not realistic. The relative wind under canopy is always from the front (unless your feet are on the ground).

I can't tell if you're joking or not Crazy


airtwardo  (D License)

Dec 7, 2012, 2:13 PM
Post #38 of 72 (1750 views)
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Re: [labrys] Question about coming back from a long spot [In reply to] Can't Post

In reply to:
Quote:
This is not realistic. The relative wind under canopy is always from the front (unless your feet are on the ground).

I can't tell if you're joking or not Crazy


In aeronautics, the relative wind is the direction of movement of the atmosphere relative to an aircraft or an airfoil.

It is opposite to the direction of movement of the aircraft or airfoil relative to the atmosphere.


Premier billvon  (D 16479)
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Dec 7, 2012, 2:15 PM
Post #39 of 72 (1749 views)
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Re: [Quagmirian] Question about coming back from a long spot [In reply to] Can't Post

>Does this actually improve absolute glide ratio, ie would you cover more ground in still air?

In general, yes. Per Brian Germain, brakes are almost always a better option than rear risers, since rear risers deform the canopy and cause a lot of drag.


Premier billvon  (D 16479)
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Dec 7, 2012, 2:18 PM
Post #40 of 72 (1746 views)
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Re: [DocPop] Question about coming back from a long spot [In reply to] Can't Post

>I am not so sure about that. Brakes add drag, using a touch of rears will improve
>the glide path without adding to the drag.

Pulling down part of the tail does indeed add some drag. Distorting the entire canopy with rear risers adds more drag.


labrys  (D 29848)

Dec 7, 2012, 2:33 PM
Post #41 of 72 (1744 views)
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Re: [airtwardo] Question about coming back from a long spot [In reply to] Can't Post

Quote:
In aeronautics, the relative wind is the direction of movement of the atmosphere relative to an aircraft or an airfoil.

I do get that... but there's a difference between the direction of movement of the atmosphere relative to an airfoil and the influence that the actual direction of the wind have on the ground speed of that airfoil.


airtwardo  (D License)

Dec 7, 2012, 2:48 PM
Post #42 of 72 (1737 views)
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Re: [labrys] Question about coming back from a long spot [In reply to] Can't Post

In reply to:
Quote:
In aeronautics, the relative wind is the direction of movement of the atmosphere relative to an aircraft or an airfoil.

I do get that... but there's a difference between the direction of movement of the atmosphere relative to an airfoil and the influence that the actual direction of the wind have on the ground speed of that airfoil.

Of course, but in the context DocPop was using it I think he's accurate. IIRC a poster he was answering asked about relative wind at his back...strictly speaking if that happens, you've put the canopy on the harness wrong.
Wink


DocPop  (C License)

Dec 7, 2012, 4:42 PM
Post #43 of 72 (1706 views)
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Re: [labrys] Question about coming back from a long spot [In reply to] Can't Post

In reply to:
Quote:
In aeronautics, the relative wind is the direction of movement of the atmosphere relative to an aircraft or an airfoil.

I do get that... but there's a difference between the direction of movement of the atmosphere relative to an airfoil and the influence that the actual direction of the wind have on the ground speed of that airfoil.

Relative wind and groundspeed are totally independent concepts.

In an uncoordinated turn when the canopy is "skidding" sideways the relative wind may be coming slightly from one side but otherwise it is from the front and slightly down (as evidenced by the fact that the pilot chute trails directly behind the wing).


DocPop  (C License)

Dec 7, 2012, 4:44 PM
Post #44 of 72 (1703 views)
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Re: [billvon] Question about coming back from a long spot [In reply to] Can't Post

In reply to:
>I am not so sure about that. Brakes add drag, using a touch of rears will improve
>the glide path without adding to the drag.

Pulling down part of the tail does indeed add some drag. Distorting the entire canopy with rear risers adds more drag.

Now that I must take issue with.

If that were the case then why would swoopers use rears to maximize their glide ("swoop") and only switch to toggles when the airspeed drops to a point where extra lift (with its attendant drag increase) is needed?

To be clear, in the long spot scenario, I am talking about a "touch" of rears, not a full plane-out.


(This post was edited by DocPop on Dec 7, 2012, 4:47 PM)


Tuna-Salad  (C 38765)

Dec 7, 2012, 6:48 PM
Post #45 of 72 (1681 views)
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Re: [Deimian] Question about coming back from a long spot [In reply to] Can't Post

My $0.02 if you are on a long spot immediately start looking for and select an alternate landing area. People get hurt when they "think" they can make it back but are not sure then end up being unprepared.


davelepka  (D 21448)

Dec 7, 2012, 7:01 PM
Post #46 of 72 (1678 views)
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Re: [StreetScooby] Question about coming back from a long spot [In reply to] Can't Post

Quote:
Keep in mind when picking a off-DZ spot to land - there are power lines next to most roads, and you might not see them until you're low. Also, when landing in fields, keep an eye out for barbed wire fences. They're very difficult to see until you're right on them,

This is the reason to use a landing pattern when landing off. It provides two major functions for off-field landings, the first one is that the downwind leg gives a great chance to 'sweep' the field at a low-ish altitude for obstacles.

As you fly the downwind leg, you're going right past your intended touchdown point at something less than 1000ft. This gives you an excellent vatage point to spot some obstacles which may have not been obvious from higher up. Gopher holes, fences, logs, etc, whatever it is, you stand the best chance of spotting it when down low.

The second advantage comes into play if you do spot an obstacle. You can use your accuracy skills to alter your turn points for your base and final legs to make sure that you end up clear of said obstacle.

The other obvious advantage of using a pattern is that it will reduce the possibility of making a low turn. If you use a pattern when landing at the DZ, and don't make low turns there, repeat that skill when landing off and it will increase your chances for success.

The thing about landing patterns and accuracy is that they seem fairly mundane and 'common-place' after so many jumps at the DZ. When everything is going well, it starts to feel like driving through an empty parking lot but still staying in between the lines. Pointless and time-consuming.

However, there is a point to those skills and developing them to a sharp point. Landing off is one of them, sudden changes in wind speed or direction is another, and traffic or other incursions would be a thrid. All fairly rare events, but when they do happen, you're going to be gald you have the skills to remain in control of the situation and make the right moves.


kallend  (D 23151)

Dec 7, 2012, 7:54 PM
Post #47 of 72 (1669 views)
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Re: [klippetop] Question about coming back from a long spot [In reply to] Can't Post

In reply to:
I've been taught, that in my big ass student canopy, when I give myself a bad spot and risk going backwards because of headwind, it's better to be at a 45 degree angle to the wind. The theory should be, that I present less canopy to the wind and by zigzagging with flat turns, I can cover more ground.

I havent done it enough times to know if it's actually working yet. Any comments from the canopy gurus? Do i burn too much altitude on the turns?

.

Bad advice. The guy probably believes in the "45 degree rule" too.


kallend  (D 23151)

Dec 7, 2012, 8:00 PM
Post #48 of 72 (1666 views)
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Re: [DocPop] Question about coming back from a long spot [In reply to] Can't Post

In reply to:
In reply to:
In reply to:
For most canopies, a little bit of brake gives you a better glide than using rear risers.
Does this actually improve absolute glide ratio, ie would you cover more ground in still air?

I am not so sure about that. Brakes add drag, using a touch of rears will improve the glide path without adding to the drag.

Of course this may be offset by the fact that holding rears for a long time is hard work.

According to John LeBlanc of PD (but what does he know???) it is very canopy dependent whether brakes or rear risers has the better result.


wolfriverjoe  (A 50013)

Dec 7, 2012, 8:02 PM
Post #49 of 72 (1665 views)
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Re: [pchapman & 'Twardo] Question about coming back from a long spot [In reply to] Can't Post

In reply to:
...There is actually a happy medium in the debate on "go for a road" vs. "go for a field":

I say, go for near a road, but not right next to it, and only to the limitation of your own skill...

That's true. I tend to be extra conservative under unusual circumstances. If the situation is not normal, I like an extra margin for error, because I know errors are more likely.

And I learned "emergency landing" concepts in a plane a long time (longer than I care to admit) before I ever even saw a sport parachute.
The power lines and fences tend to be harder to see in time from an airplane than under canopy, and last second changes in plan are a lot easier under canopy.

So maybe the "middle of a huge field" is an over-reaction, or continuing on from what I was taught in my FJC. Or maybe a little lack of confidence in my accuracy under odd circumstaces.


DocPop  (C License)

Dec 7, 2012, 8:36 PM
Post #50 of 72 (1656 views)
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Re: [kallend] Question about coming back from a long spot [In reply to] Can't Post

In reply to:
In reply to:
In reply to:
In reply to:
For most canopies, a little bit of brake gives you a better glide than using rear risers.
Does this actually improve absolute glide ratio, ie would you cover more ground in still air?

I am not so sure about that. Brakes add drag, using a touch of rears will improve the glide path without adding to the drag.

Of course this may be offset by the fact that holding rears for a long time is hard work.

According to John LeBlanc of PD (but what does he know???) it is very canopy dependent whether brakes or rear risers has the better result.

Did he say that in still air?

What exactly was the context?


Quagmirian  (A 110392)

Dec 8, 2012, 1:32 AM
Post #51 of 72 (2149 views)
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Re: [DocPop] Question about coming back from a long spot [In reply to] Can't Post

When people talk about about using brakes to 'improve your glide' when coming back from a long spot I've always struggled to understand whether this is purely because you stay in the air longer or if your canopy's glide ratio is affected at all.


pchapman  (D 1014)

Dec 8, 2012, 3:21 AM
Post #52 of 72 (2136 views)
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Re: [Quagmirian] Question about coming back from a long spot [In reply to] Can't Post

In reply to:
I've always struggled to understand whether this is purely because you stay in the air longer or if your canopy's glide ratio is affected at all.

No time for a careful answer but it can be "both". The canopy's descent rate is lower, which is the big thing. But forward speed is down too, the actual glide ratio (thru still air) is probably better, if one is comparing zero to moderate brakes. Somewhere in deeper brakes though, there the glide ratio might get worse. Even then, one might still be doing better in getting back, having a better glide ratio over the ground. (If it is windy enough, a piece of confetti will get back to the DZ, even though it's glide ratio is roughly straight down in still air...) As usual, things depend somewhat on canopy style, as to at what point adding brakes makes the glide ratio in still air worse and not better.

To really understand glide ratio in still air and the glide in wind, one needs to understand "glide polars" and how to shift them for wind. If one found some glider pilot resource on the web that would help, but I don't know of any site off hand.

In typical cases, what one loses in forward speed from going to brakes, is more than made up for by having lower descent rate, when there's a tailwind that's giving you "free forward speed" over the ground. But that's when it is fairly windy. When winds are lower the answers are less simple regarding what canopy controls will be best for your canopy that day.

In practice once can of course try to use the accuracy trick of seeing whether one's target of the DZ is moving up or down in one's visual field, and play with brakes or risers to see what works with the current conditions on your canopy.


davelepka  (D 21448)

Dec 8, 2012, 5:15 AM
Post #53 of 72 (2124 views)
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Re: [DocPop] Question about coming back from a long spot [In reply to] Can't Post

Quote:
What exactly was the context?

What was the context of your statement? You made the reference to swoopers using rears, and that it must be more efficient or they wouldn't be doing it, but I think you're only dealing with half of the story.

Rears can be an asset, but only to a point. When you pull down on the rears, there is a portion of the travel that will flatten out the trim without distoring the canopy. Essentially, the inflated wing pivots downward off the A line attachment points, which effectively flattens out the glide.

However, this only works (well) for a very small portion of the travel. What happens if you pull too hard, is that the B lines will being to slack, and a crease will form in the canopy. At this point, you're no longer simply re-trimming the canopy, now your bending it half and pulling the rear half down into the wind, aka creating drag.

When swooping, that first little bit of travel actually gets bigger becasue of airspeed. When the pressurization is up, like at the tail end of a big turn, your canopy will hold it's shape longer than when pulling the rears in slow flight. On top of that, you have the concept of control effectiveness going up with airspeed, so again, at the bottom of a big turn, a little goes a long way.

So when it comes to ultra-high speed flight, and for minor trim changes to level your canopy for a swoop, the rears are the ticket. Once you're into them for the swoop, it makes the most sense to fly them out to a degree, but as it's commonly known, you don't fly them out to 100% just before the stall before you transition, you need to dump them and go to toggles at about 80% of what they have to give.

When it comes to steady-state flight at slow speeds, the brakes are far more reliable in terms of efficiency, and more forgiving in terms of the jumpers need for accurate inputs (both being good things when trying to cover long distances over 'long' periods of time).


(This post was edited by davelepka on Dec 8, 2012, 5:16 AM)


DocPop  (C License)

Dec 8, 2012, 8:02 AM
Post #54 of 72 (2100 views)
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Re: [davelepka] Question about coming back from a long spot [In reply to] Can't Post

I agree with you Dave.

The context of what I wrote was that I was disagreeing with billvon's blanket statement about the drag induced by rears vs toggles:

Quote:
Pulling down part of the tail does indeed add some drag. Distorting the entire canopy with rear risers adds more drag.


I also gave the following caveat in my statement in post 44:

Quote:
To be clear, in the long spot scenario, I am talking about a "touch" of rears, not a full plane-out.

My point being that used correctly, rears will improve glide ratio with less drag than toggles (or "brakes" as the are also known for some bizarre reason!Wink)


muff528  (D 17609)

Dec 8, 2012, 8:29 AM
Post #55 of 72 (2098 views)
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Re: [Tuna-Salad] Question about coming back from a long spot [In reply to] Can't Post

In reply to:
My $0.02 if you are on a long spot immediately start looking for and select an alternate landing area. People get hurt when they "think" they can make it back but are not sure then end up being unprepared.

Yep. I've always tried to spot the landing area and try to see which direction it appears to be going. If it gives the illusion that it is "ascending" towards the horizon (or away from me), I know I'm not going to make it and I look for an alternate landing area. If it appears to be "descending" (moving down and away from the horizon but towards me) I'll probably make it OK. Also, I'm in the release-the brakes-and-check-controls-first camp. The outcome of the control check would probably influence other decisions I might have to make.


skyjumpenfool  (Student)

Dec 8, 2012, 11:01 AM
Post #56 of 72 (2071 views)
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Re: [muff528] Question about coming back from a long spot [In reply to] Can't Post

In reply to:
Also, I'm in the release-the brakes-and-check-controls-first camp. The outcome of the control check would probably influence other decisions I might have to make.

Agree and disagree. If I've pulled at normal pull altitude and the opening appears to have gone smoothly, I like to look around for traffic while harness turning towards the DZ before brake release. I can also check my slider and give the canopy a good look during this time.

Since this only takes 2-3 seconds, I should not have lost a lot of altitude (under a good canopy) in that time. If I have to go to EP's, I have a better understanding of where I, and others, are. Plus, I'm now flying in the correct direction while doing control checks.


muff528  (D 17609)

Dec 8, 2012, 11:29 AM
Post #57 of 72 (2062 views)
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Re: [skyjumpenfool] Question about coming back from a long spot [In reply to] Can't Post

In reply to:
....... I like to look around for traffic while harness turning towards the DZ before brake release. I can also check my slider and give the canopy a good look during this time.

Since this only takes 2-3 seconds, I should not have lost a lot of altitude (under a good canopy) in that time. If I have to go to EP's, I have a better understanding of where I, and others, are. Plus, I'm now flying in the correct direction while doing control checks.

Yeah, I agree with all that stuff immediately after opening. But then, for the flight back to the DZ, I agree with releasing the brakes first rather than leaving them stowed in hopes that that would help flatten the glide slope a little ...and then finding out, when the brakes are finally released, that there is a control problem.


D22369  (D 22369)

Dec 8, 2012, 1:07 PM
Post #58 of 72 (2044 views)
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Re: [Deimian] Question about coming back from a long spot [In reply to] Can't Post

maybe it is plainly a very stupid question?
Quote:

damned good question if ya ask me,
you have some great answers from others, only thing I can think of to add is to take it to the air with another person on a similarly loaded canopy and use them as a point of reference to see what full flight, brakes, rear risers and front risers will do for you. not saying to attempt a dock or anything *(crw) just just flying in proximity

I used to film those crazy CRW guys on my stiletto and found a use for each configuration - I learned a tremendous amount about each flight configuration in those first few jumps with them.

Roy


kallend  (D 23151)

Dec 8, 2012, 2:25 PM
Post #59 of 72 (2032 views)
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Re: [muff528] Question about coming back from a long spot [In reply to] Can't Post

In reply to:
In reply to:
....... I like to look around for traffic while harness turning towards the DZ before brake release. I can also check my slider and give the canopy a good look during this time.

Since this only takes 2-3 seconds, I should not have lost a lot of altitude (under a good canopy) in that time. If I have to go to EP's, I have a better understanding of where I, and others, are. Plus, I'm now flying in the correct direction while doing control checks.

Yeah, I agree with all that stuff immediately after opening. But then, for the flight back to the DZ, I agree with releasing the brakes first rather than leaving them stowed in hopes that that would help flatten the glide slope a little ...and then finding out, when the brakes are finally released, that there is a control problem.

There was a a fatality on a 124 way at Perris some nine years ago that is thought due to a common habit at that time on big ways of not releasing brakes until under 1,000ft. The jumper had her excess brake line hang up on a Slink connector. There is a long thread in the "Incidents" forum about it.

1,000ft is too low for a safe cutaway if you have a toggle or steering line or other steering related problem that only becomes apparent when you go to release the toggles.

You should be sure by your hard deck that you have a good, STEERABLE canopy over your head.


rmarshall234  (D 18793)

Dec 8, 2012, 9:49 PM
Post #60 of 72 (1977 views)
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Re: [Deimian] Question about coming back from a long spot [In reply to] Can't Post

I can tell you what Jonathan Tagle would say, from experience:

"I don't know. Go try it and find out."


jonathan.newman  (D 30644)

Dec 9, 2012, 7:43 PM
Post #61 of 72 (1901 views)
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Re: [pchapman] Question about coming back from a long spot [In reply to] Can't Post

Try this, Mr. pchapman, and from a Canuck website, with pictures, and animation, no lessWink http://avia.tion.ca/documentation/polar/

Once you understand the polar curve, come back and keep reading.

Our canopies actually have two different polar curves. One comes from using only riser input, and the other comes from using only toggle input. Full flight seems to be somewhere on the right side of the curve. If I pull front risers, I can increase my airspeed and increase my rate of descent -- thus moving to the right and down on the curve. If I pull rear risers or toggles, I will both slow my airspeed and my descent rate -- moving left on the curve. (this works up to the point where the wing begins to mush and then stalls)

So, if you can trust what the glider pilots believe, then if you are trying to make it back to the DZ with a tailwind, then use rear risers or brakes to increase your glide angle. And if you have a headwind, then picking up speed with front risers will get you farther.

That's great in theory, but since we have neither GPS nor variometers, and our airspeed is judged by our ears, we need some way to gauge how much toggle or riser input to provide.

That is where the "accuracy trick" comes into play.

Now, before anyone jumps on me to say that they took a canopy course and learned sumthin' different, let me say that I took a Flight1 course and was taught brakes with a tailwind, rears with a headwind. In theory, I disagree with that, and will try to play around with it while I'm jumping this week.


Premier slotperfect  (D 13014)

Dec 10, 2012, 2:51 AM
Post #62 of 72 (1871 views)
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Re: [jonathan.newman] Question about coming back from a long spot [In reply to] Can't Post

Quote:
Now, before anyone jumps on me to say that they took a canopy course and learned sumthin' different, let me say that I took a Flight1 course and was taught brakes with a tailwind, rears with a headwind. In theory, I disagree with that, and will try to play around with it while I'm jumping this week.

I will be very interested to hear the results of your experiment.

I used rear risers to recover from long spots for years. Then I took a Scott Miller course and learned that deep brakes work better - slowing the descent rate as much as possible to allow the tailwind to carry you for a longer time. I made two identical jumps using the same spot from the same altitude and was very surprised at the difference.

I used front risers to recover from being short (into a headwind) for years. Then I took a Flight-1 course and learned that a bit of rear risers and a small body position to reduce drag works better. Front risers work, but at the expense of more altitude loss, and they are more difficult to sustain over longer periods of time. I was skeptical of this at first (contrary to years of using another method), but when I got home and used this technique for real when I was in a pinch, I discovered that it really works.

The best way to see how rear risers work is flying side-by-side with another canopy. From the flight mode that matches your partner allowing you to stay in place, engage rears slightly and use a small body position and you should pull in front of your partner staying on level or climbing very slightly.

I use rears for crosswinds as well, or full flight (each with a crab), depending on how far off the wind line I am at the time.


Premier slotperfect  (D 13014)

Dec 10, 2012, 2:52 AM
Post #63 of 72 (1868 views)
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Re: [kallend] Question about coming back from a long spot [In reply to] Can't Post

Quote:
You should be sure by your hard deck that you have a good, STEERABLE canopy over your head.

+1 -- great advice.


Premier billvon  (D 16479)
Moderator
Dec 10, 2012, 9:00 AM
Post #64 of 72 (1807 views)
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Re: [DocPop] Question about coming back from a long spot [In reply to] Can't Post

>If that were the case then why would swoopers use rears to maximize their glide
>("swoop") and only switch to toggles when the airspeed drops to a point where extra
>lift (with its attendant drag increase) is needed?

Because recovering a canopy from an unstable dive to achieve maximum speed and/or distance just above the ground is different than maximizing L/D in steady state conditions.


dthames  (B 37674)

Dec 10, 2012, 10:29 AM
Post #65 of 72 (1785 views)
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Re: [slotperfect] Question about coming back from a long spot [In reply to] Can't Post

Slotperfect,

Quote:
I used rear risers to recover from long spots for years. Then I took a Scott Miller course and learned that deep brakes work better - slowing the descent rate as much as possible to allow the tailwind to carry you for a longer time. I made two identical jumps using the same spot from the same altitude and was very surprised at the difference.

Would the success of the "deep brakes" being better depend on how strong the tailwind is? I mean if your tail wind was pretty weak, wouldn't you be better off keeping the canopy's flying speed up? (rear risers)


linebckr83  (D 30571)

Dec 11, 2012, 6:28 AM
Post #66 of 72 (1683 views)
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Re: [dthames] Question about coming back from a long spot [In reply to] Can't Post

In reply to:
Slotperfect,

Quote:
I used rear risers to recover from long spots for years. Then I took a Scott Miller course and learned that deep brakes work better - slowing the descent rate as much as possible to allow the tailwind to carry you for a longer time. I made two identical jumps using the same spot from the same altitude and was very surprised at the difference.

Would the success of the "deep brakes" being better depend on how strong the tailwind is? I mean if your tail wind was pretty weak, wouldn't you be better off keeping the canopy's flying speed up? (rear risers)

Naturally yes. If your tailwind is basically nothing, floating in deep brakes will not be extremely effective as you are also slowing your airspeed down considerably while in brakes. In that configuration you are essentially "riding the wind". No wind, not much movement. Rear risers would be a better bet since you will have forward movement because of your airspeed.

What is the point where you switch gears from rear risers to riding in brakes? That's where differences in wind, windloading, and canopy trim/design come in to play. Your best best is to take yours up and play with it!


DocPop  (C License)

Dec 12, 2012, 2:38 AM
Post #67 of 72 (1608 views)
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Re: [billvon] Question about coming back from a long spot [In reply to] Can't Post

In reply to:
>If that were the case then why would swoopers use rears to maximize their glide
>("swoop") and only switch to toggles when the airspeed drops to a point where extra
>lift (with its attendant drag increase) is needed?

Because recovering a canopy from an unstable dive to achieve maximum speed and/or distance just above the ground is different than maximizing L/D in steady state conditions.

That is basically just you saying "because I said so", and is not satisfactory. I suspect you have no way to back up your original assertion.


potatoman  (Student)

Dec 12, 2012, 7:21 AM
Post #68 of 72 (1569 views)
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Re: [klippetop] Question about coming back from a long spot [In reply to] Can't Post

OK, back to the 45degree to the wind and zigzagging it, when going upwind, or wind into face to LZ.

I cannot help to think, never tried though, that it might be worthwile to do consecutive 45degree turns, rather sharply, and then still get penetration.

So, 22,5degree to the wind, do a sharp turn so you end up at 22,5 degree oposite side, BUT, increased speed from the turn should give you some penetration, once you feel penetration is now nearly over, do the same again to the other side.

I am not talking front risers, but toggles, and I know that would probably be 3steps forward two back...

I have to go and test this......


davelepka  (D 21448)

Dec 12, 2012, 7:31 AM
Post #69 of 72 (1565 views)
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Re: [potatoman] Question about coming back from a long spot [In reply to] Can't Post

Quote:
OK, back to the 45degree to the wind and zigzagging it, when going upwind, or wind into face to LZ.

The shortest distance between two points is a straight line. When dealing with a headwind, and the reduced glide it offers, you have a limited supply of 'distance' to work with. Zig-zagging will only make your trip to the LZ (or wherever you end up short of the LZ) that much longer.

On top of the that, the increase in speed you're counting on will come at the expense of altitude. Remember the limited supply of 'distance' mentioned above, your repeated turns will only wear that down even further.

It sounds more like one step back, followed by another step back.


(This post was edited by davelepka on Dec 12, 2012, 7:32 AM)


Premier slotperfect  (D 13014)

Dec 12, 2012, 8:14 AM
Post #70 of 72 (1549 views)
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Re: [dthames] Question about coming back from a long spot [In reply to] Can't Post

THe short answer is yes, but we are talking about wind conditions that provide a useful tailwind that can be harnessed. A very light or nonexistent wind does not provide a condition that allows for use of either technique. In that case, normal use of flight modes applies and you may have to pick an alternate for landing.


kallend  (D 23151)

Dec 13, 2012, 8:45 PM
Post #71 of 72 (1465 views)
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Re: [jonathan.newman] Question about coming back from a long spot [In reply to] Can't Post

In reply to:

So, if you can trust what the glider pilots believe, then if you are trying to make it back to the DZ with a tailwind, then use rear risers or brakes to increase your glide angle. And if you have a headwind, then picking up speed with front risers will get you farther.

Well, that is ONLY true IF the canopy is already trimmed for best glide. Most sport canopies, however, are already trimmed to fly steeper than best glide speed, so unless the headwind is really really strong (like you're backing up) front risers won't help.


Mac  (C 101464)

Dec 20, 2012, 3:06 AM
Post #72 of 72 (1334 views)
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Re: [slotperfect] Question about coming back from a long spot [In reply to] Can't Post

In reply to:
... and you may have to pick an alternate for landing.

Continue all along your flight to pick out alternative landing areas at each stage. Once you go over your current choice, reassess, and scope another. If you look to be putting yourself into a maybe/maybe not situation on making it back toward the end of the canopy flight, ensure you have an alternative landing zone already in the bag, do not attempt it if there isnt an alternative prior to making it back if you are still on a maybe/maybe not.

Better to land off then panic attempting to avoid something because your eye was slightly off or the conditions on the last few hundred feet changed.



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