On near-zero-wind High Rock launches

Spark · Post by **Spark** » Mon Feb 14, 2005 8:08 pm

Regarding Bacil's recent comment: "A near zero wind launch at High Rock is one of the most risky and difficult launches there is at High Rock"

Bacil, Please don't interpret this as disrespect. I haven't flown the Rock nearly as much as some - only 102 times in the past five years - but I just don't perceive the same risk. I recall and affirm what has been said before: High Rock is one of our safest launches. It seems sorta counter-intuitive, but I believe it. In fact, I believe light wind (not cross wind) conditions at HR are the safest conditions. Don't get me wrong - the HR launch is to be taken very seriously.

I'm thinking that in near-zero conditions, the 70 foot+ cushion of air below the Rock reduces the risk substantially. I won't deny that the drop adds a significant perception of risk for those with mild to severe acrophobia. (Frankly, that is why I like to watch wuffos watch sled-launches at the Rock) I'm inclined to believe that the most risky and difficult launches at the Rock are in gusty cross-wind conditions (in particular, west-cross).

I am wondering ... how much extra airspeed do you gain from those two or three steps (i.e. how fast can you accelerate in 6 feet)? Do the extra steps increase the potential for 'nose-popping'? Are those extra steps worth the small increase in speed? I believe that taking extra steps can increase the risk.

Another thought ... is it possible that you could gain that same airspeed by losing five or ten (or twenty) feet of altitude, using the proper AOA?

I'm thinking the real value of taking a stride or two is to provide the required momentum and separate your wing from the snagging edge. I have flown from cliff-launch sites in very light conditions (potosi mtn in NV, Donner summit in CA) that provide room for only one step.

Technique (not the distance you run) is the determining factor.

In calm air at the Rock, with proper technique, I suspect one could lean forward and simply 'fall' off the edge without diving out. I recall watching Greg DeWolf do something very much just like that at HR.

I would never try a 'no-step-launch' in light air at HR because it is not necessary. On the other hand, I don't really feel like I need to start from the back of the block.

One thing I have learned for sure about light air at the Rock: regardless of how far you run, if you pull in on the bar as a you go off the edge, you will probably dive farther than you would expect. Another thing I've learned is that if you dive out on launch, there is plenty of altitude to recover.

I used to dive out every launch (I think it is kinda fun), until I finally realized (i.e. decided that I cared) that it scared the spectators and set a bad example for the other pilots. ... So I stopped pulling in, and I stopped diving out.

'Spark

===============================================
Here's some food for thought on Hang IIs launching at High Rock in near zero wind. A near zero wind launch at High Rock is one of the most risky and difficult launches there is at High Rock. You only get a few steps in before you run out of cube, the nose angle must be maintained at the optimum AOA throughout the short takeoff run, and there is a tendency to jackrabbit start when faced with only a few steps of runway length. Jackrabbit starts usually pop noses, making the takeoff less than optimal. The glider sometimes banks, almost always dives, and usually scares the inexperienced pilot with the view of the trees rushing up. If anything, I would think that an 8 to 12 MPH straight in wind would be the optimum conditions for newbies at High Rock to launch in.

Bacil

Post by **mcgowantk** » Mon Feb 14, 2005 10:40 pm

I agree that High Rock is one of our safest launches - it is most likely the safest in that we have so few blown launches there.? I have gone through a cycle of launching there where I used to run hard off the end in light cycles.? But now I try to launch closer to the edge and just take 1 1/2 steps so that I clear the edge of the ramp a little more.? I launch closer to the edge for two reasons:? first, I can control my angle of attack better with fewer steps.? Second, because I am now always at the edge, I don't have to make decisions on when it is too strong to run off from the back of the lauch (e.g., it's blowing 8 mph - is that too strong to run off or should 10 mph be my limit?).? I hope to get to the point when I pretty much do the same thing on each launch.
?
I am still working on the diving off stuff.? I pull in a little?to gain air speed, but agree that you can over do it.? Some may think I typically dive further than I perceive I am, but I am still learning.? That helps make this so much fun.
?
On a different topic, I am ready to take a day.??I believe Thursday has some potential, or maybe Friday.
?
Tom McGowan

Spark <BagPipeFlyer@hotmail.com> wrote:

Regarding Bacil's recent comment: "A near zero wind launch at High Rock is one of the most risky and difficult launches there is at High Rock"

Bacil, Please don't interpret this as disrespect. I haven't flown the Rock nearly as much as some - only 102 times in the past five years - but I just don't perceive the same risk. I recall and affirm what has been said before: High Rock is one of our safest launches. It seems sorta counter-intuitive, but I believe it. In fact, I believe light wind (not cross wind) conditions at HR are the safest conditions. Don't get me wrong - the HR launch is to be taken very seriously.

I'm thinking that in near-zero conditions, the 70 foot+ cushion of air below the Rock reduces the risk substantially. I won't deny that the drop adds a significant perception of risk for those with mild to severe acrophobia. (Frankly, that is why I like to watch wuffos watch sled-launches at the Rock) I'm inclined to believe that the most risky and difficult launches at the Rock are in gusty cross-wind conditions (in particular, west-cross).

I am wondering ... how much extra airspeed do you gain from those two or three steps (i.e. how fast can you accelerate in 6 feet)? Do the extra steps increase the potential for 'nose-popping'? Are those extra steps worth the small increase in speed? I believe that taking extra steps can increase the risk.

Another thought ... is it possible that you could gain that same airspeed by losing five or ten (or twenty) feet of altitude, using the proper AOA?

I'm thinking the real value of taking a stride or two is to provide the required momentum and separate your wing from the snagging edge. I have flown from cliff-launch sites in very light conditions (potosi mtn in NV, Donner summit in CA) that provide room for only one step.

Technique (not the distance you run) is the determining factor.

In calm air at the Rock, with proper technique, I suspect one could lean forward and simply 'fall' off the edge without diving out. I recall watching Greg DeWolf do something very much just like that at HR.

I would never try a 'no-step-launch' in light air at HR because it is not necessary. On the other hand, I don't really feel like I need to start from the back of the block.

One thing I have learned for sure about light air at the Rock: regardless of how far you run, if you pull in on the bar as a you go off the edge, you will probably dive farther than you would expect. Another thing I've learned is that if you dive out on launch, there is plenty of altitude to recover.

I used to dive out every launch (I think it is kinda fun), until I finally realized (i.e. decided that I cared) that it scared the spectators and set a bad example for the other pilots. ... So I stopped pulling in, and I stopped diving out.

'Spark

===============================================
Here's some food for thought on Hang IIs launching at High Rock in near zero wind. A near zero wind launch at High Rock is one of the most risky and difficult launches there is at High Rock. You only get a few steps in before you run out of cube, the nose angle must be maintained at the optimum AOA throughout the short takeoff run, and there is a tendency to jackrabbit start when faced with only a few steps of runway length. Jackrabbit starts usually pop noses, making the takeoff less than optimal. The glider sometimes banks, almost always dives, and usually scares the inexperienced pilot with the view of the trees rushing up. If anything, I would think that an 8 to 12 MPH straight in wind would be the optimum conditions for newbies at High Rock to launch in.

Bacil

'Spark

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Post by **XCanytime** » Mon Feb 14, 2005 10:50 pm

Spark,
???? No problem.? Just discussing.? I'm just thinking from the newbie's perspective of launching from High Rock for the first time (they have never done a cliff launch before).? Airspeed for free from a straight in 8 to 12 MPH smooth wind is, I feel, a less intimidating option to the newbie pilot than trying to generate airspeed from only a few steps.? The biggest problem an inexperienced pilot faces on cliff launches in calm conditions is getting the nose too high and stalling at the edge.? High Rock in calm conditions allows a safe launch since there is ample clearance in front of the cube to dive for airspeed.? This is considered an advanced technique (according to Pagen) and should be left to experienced pilots (according to Pagen).? The general advice for inexperienced pilots is to watch plenty of calm High Rock launches before attempting one themselves.

??????????????????????????????????????????????????????? Bacil

Scott · Post by **Scott** » Tue Feb 15, 2005 7:26 am

I haven't been flying for a couple months, so I probably should keep my mouth shut.

The whole no-wind cliff launch discussion is fascinating because I learned a lot about this on my Tennessee trip last fall (where both Lookout and Henson's are cliff launches...well, Henson's isn't technically a "cliff," but it's not a "slope" either!)

I popped the nose a bit on my first Lookout launch. So did Holly and a bunch of other people. I thought about it a LOT, why it happened, how to prevent it, etc. Then I remembered a simple bit of advice Steve Wendt gave me on the training hill: keep your hands by your sides. Not literally by your sides, but what he meant was keep your hands lower on the downtubes, down in front of/beside your hips.

When I was hill training with John M., I always thought "head through the control frame and push with my shoulders." (I don't remember if John ever told me that, or more likely that's just how I interpreted it all.) In my case, I think that resulted in my shoulders acting like a sort of fulcrum---I'd start a run, and the wing (with all that leverage) would just roll back and up. I was running like an angry bull---head down and charging!

Now, I think of my "launch propulsion system" as being a "4-point vertical system" (two hands and two shoulders, head up, back straight) as opposed to a "2-point horizontal system" (shoulders only with the hands just going along for the ride, head down, bent forward). Even if it happens in the span of a second or two, (and even if I only have 6 feet to do it) I now think "walk, jog, run" instead of "RUN!!!" This, combined with keeping my hands low, combined with Matthew's point about standing upright (which Steve also pointed out)...all collectively make it very difficult to pop the nose.

This may all be in the "NO DUH" category, but I'm just making finer points about how I thought about carrying/running with the glider.

It made a big difference for me. I don't claim my launches are excellent either! I know I've got plenty of continued work ahead and look forward to it.

Scott