Garlock 02.26

A place to stretch the truth a little...
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JBBenson
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Joined: Thu May 12, 2005 9:19 am

Garlock 02.26

Post by JBBenson »

Greblo led a gaggle of us to Garlock early Sunday. Myself, Lynden, Don, Chris, Eric and Kris Greblo.

Beautiful desert scenery on the way: trucks with dirt-bikes, cozy little meth- labs settled amonst the rocks, and a strange 6-wheeled vehicle driven by black-masked militants: Minutemen perhaps?

After setting up, we waited out the hail (!) and made a sledder to the LZ, trying an impromptu spot landing. I crashed and still came in third.

We drove back up, as the sun was coming out. Launch this time was in gusty 14-18, a little intimidating, but Joe saw that I got off the mountain
safely. Conditions at altitude were great, we all soared for awhile. Then things got interesting.

The relatively smooth south-westies ratched up to probably at least 25-30 within about 30 seconds. The air grew very turbulent and the lift went from a balmy 350/min to 1200+ in some places. Scary stuff, at least for me.

Hello, Pre-Frontal.

I was thinking about three things: getting away from the ridge ASAP; looking for an alternate LZ (my groundspeed was about 3-5 MPH); and seriously considering if this was the flight where I would toss my 'chute. It was that rowdy. I wasn't the only one who felt this way: heard alot of cursing on the radio. Sorry Mr. FCC, it was an emotional moment....

Entering the gradient enabled me to move away from the ridge and the dreaded rotor. Made it out to the LZ and landed safely.

That got my attention. It was first time I was wishing I was on the ground. Like right now please...

Excellent guidance and instruction and good (learned) habits made for a interesting and enlightening experience, instead of the other kind...
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Christian
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Location: Pacific Palisades

Post by Christian »

Thanks for the report, I was wondering how that trip went. Where is Garlock, more or less? Anywhere near Red Rock Canyon on the way to Mammoth, where on Friday I was passing through and looking at what seemed to be scores of potential flying sites?
JBBenson
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Post by JBBenson »

http://www.mapquest.com/maps/map.adp?se ... A&zipcode=


I think launch is west of the star somewhere. Pretty remote. There is also a neat dry lake bed that is not indicated on the map.

Forgot about what looked like a F-80 with tip tanks (butterfly tail?) streaking BELOW us, about 250 AGL, heading west. Quite a sight. Think he noticed us?
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Lucky 13
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Location: It's all about the location

Post by Lucky 13 »

I went there also, that was some interesting weather, but really pretty. I'm glad I went. Some strange turbulence and air pockets, and the fighter jet 150 feet off the groung was cool too. I'm glad I didn't have a midair with that! Wow!
Garlock is a scenic neat dessert location if you've never been there, you should check it out. Neat old gold mines nearby.
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Don
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Garlock Location

Post by Don »

Launch 35'25.134 117'51.047 at 4,780 MSL

LZ 35'23.111 117'50.244 at 1950 MSL

www.topozone.com
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Christian
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Location: Pacific Palisades

Post by Christian »

Jesse, would you post here your crosswind takeoff analysis which appeared elsewhere? It was very useful I thought.
JBBenson
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Post by JBBenson »

Here it is.
I was guilty of making assumptions about how to deal with crosswind take-offs, Joe Greblo set me straight. As usual.

Here is my mail to him and his reply:

On Feb 27, 2006, at 10:51 PM, Jesse Benson wrote:

Hi Again:

A Garlock question re: yawing vs. letting the nose rotate into the
wind:
Remember when I was struggling on launch to yaw the glider? The
trouble I was having?
Why was it important in this case to yaw the glider perpendicular to the
ramp? Isn't the protocol to let the glider yaw itself into the wind,
regardless whether or not it aligns with the intended launch ramp?

As relative wind increases with the launch run, shouldn't the glider
start to yaw back into alignment with the launch run?

Or did it have to do with the strength or gusty-ness of the wind, (14-19) ?
That I could not run fast enough to overcome true wind direction?
And thus have a "crabby" or unstable launch?

I understand the logic at Kagel, with keeping both wingtips in the same
airflow (not letting one tip peek out too far over/behind the edge
I mean), but at Garlock this was not the case. Or was it? I don't think so.

Just wondering

Thanks

Jesse

Joe's reply:

Great question Jesse;
Sounds like you already have a good insight into this, but let me put
it into words.
If your wings remain balanced when your nose is into the wind, then
it's proper to let the nose point into the wind.

There is one thing that trumps all others when it comes to where to
point your nose. It is not always into the wind, but it should
always be "wherever the wing find themselves in roll balance".
In the case of your launch conditions, the wind was cross and the
glider wanted to point slightly to the right of the launch path.
Every time you allowed the glider to yaw into the wind (to the right)
the left wing lifted and you were forced to try to bring it back
down. Launching with a wing trying to lift is never a good idea.
Instead you want to be able to stand there with the wings in "roll
balance", or put another way, with neither wing trying to lift.

The reason this happened on this slope in a cross wind is because
when you allowed your nose to point into the wind, your right wing
was back away from the steeper drop off OR more in the wind gradient,
and your left wing was forward, higher in the gradient and more into
the lift band.

Next time you go to Dockweiler, try this experiment to illustrate this.

When it's blowing straight in at the northern most slopes, walk your
glider over to the middle slopes that face more southerly. Walk your
glider into launch position with your nose into the wind. As you get
very close to the top edge of the slope, you'll notice that your left
wing will be sticking out into the lift band and your right wing will
be back behind the top edge of the hill (over flat ground). Notice
that the wing that's "out in the lift band" is achieving a higher
angle of attack (and out in rising air), causing it to lift.

There are 2 common ways to remedy this problem and only one if
correct. First the wrong way.

All to often, pilots allow the glider to yaw into the wind which
causes one wing to rise. Next they try to keep the rising wing down
with weight shift or pulling down on the rising downtube. This is
dangerous as your launching with a glider that's trying to put you
into a turn.

The correct way is to force the nose away from the wind with a yaw
command on the downtubes. You do this until you find the point at
which the wings are in "roll balance" (neither wing is trying to
lift). This will require constant effort as the glider will obviously
want to yaw back into the wind if you relax for even a moment. As
long as you continue to hold the nose in the direction that keeps the
wings balanced, you do not have a glider trying to roll you off course.

Some times pilots who try to do this, make the mistake of relaxing
this yaw force at the moment they start their run. This mistake
causes the glider to begin to yaw back into the wind and lift the
wing. The trick is to continue to apply whatever yaw force is
necessary to keep the wings in balance as you accelerate through your
run. I call this technique "Using Your Rudder". Airplanes have
rudder for this purpose, and with this trick, so does your hang glider.

Let me know if makes total sense or if it's still a little confusing.

Joe

(I find the idea of a "rudder" a very useful mental image, thinking of it as a control input, not as muscling against the wind. - Jesse)
JBBenson
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Joined: Thu May 12, 2005 9:19 am

Post by JBBenson »

(the forum cut off the last part, here it is...)

(cont.)

Some times pilots who try to do this, make the mistake of relaxing
this yaw force at the moment they start their run. This mistake
causes the glider to begin to yaw back into the wind and lift the
wing. The trick is to continue to apply whatever yaw force is
necessary to keep the wings in balance as you accelerate through your
run. I call this technique "Using Your Rudder". Airplanes have
rudder for this purpose, and with this trick, so does your hang glider.

Let me know if makes total sense or if it's still a little confusing.

Joe

(I find the idea of a "rudder" a very useful mental image, thinking of it as a control input, not as muscling against the wind. - Jesse)
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Frederick
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Crosswind launching

Post by Frederick »

Wow, that sure clears it all up
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