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#1 Antonsoarer May 05, 2010 08:38 AM

Small site DS?
 
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Anyone else had any results DS'n very small sites?

I don't have any decent DS sites locally so I had a go at a hill-fort cut on top of a local site. I was really surprised at the sound and acceleration! I now see why DS at any speed is so addictive. I was only able to manage asymmetric DS circuits (judging by the single loud 'crump' sound) losing everything I had gained as I came round for another dive in. It was interesting to note how the smoother air delivered more acceleration and passing thermals killed it.

Missing the lip by inches added to the fun and I soon learnt that gentle turns delivered the most but I think I need a purpose built model to retain the gains. This site is covered in dense heather and I was using a robust composite design so impacts were no issue.

I have seen the Co guys doing road cut DS which looked similar but this site is much smaller and the shear makes a lot of noise.

Once I sort out a new design I am thinking I will need to do about 40' circuits to keep things moving, without a gyro I imagine my reflexes won't be able to correct things quick enough.

Tony.

#2 1-26 Flyer May 05, 2010 10:56 AM

Keep at it... small sites are always a huge challenge and when the time comes to get to fly at a big site you will be amazed at how much easier it is.

#3 Daemon May 05, 2010 01:18 PM

Ya, we've DS'ed road cuts that are only one lane instead of two, which is about
the scale that you're working with. If there's a place with wind, and another
without wind, you can DS between them if you've got a plane that'll make the turns
efficiently.

I've not had much luck with flat ground bush/hedge and tree DSing but we know
it's possible.

ian

#4 1000MPH May 05, 2010 01:38 PM

http://static.rcgroups.com/forums/at...858.1_1_1.jpg?
We have a slope called Red Rock that has a backside about 15' high. Before I knew what I was doing I tried to DS it with disasterous results. After learning to DS the "proper" way it was challenging but lots of fun. The spot is just West of the Reno air race site.
Here's a pic that is of no help.

#5 gizzo May 05, 2010 06:30 PM

1 Attachment(s)
A buddy and I have been having fun DSing this carpark, on top of a cliff about 100' high with the bushes on the very edge, makes quite a calm area. The circuit goes from the bushes in front (or out the front, depending what you feel like) and the nature strip by the road, by the small pine trees. very small circle compared with a big hill. Just yesterday Dave was ripping it with his Gulp DS. Just up the path is another bush that can be DS'ed behind with a weael or some such, about 15' laps will do it. A hill fort, I wish. Luxury...

#6 Swoopdown May 05, 2010 09:36 PM

I have even done small laps with a Bee behind a few shrubs. Ugly but it worked.
Lots of fun and great for the reflexes though tough on models.

#7 grael May 07, 2010 04:44 AM

I'm a new pilot, only been at it about 3 months, but gliding, and I'm 43.

Our local slope is actually a cliff, but there's a valley next to it that I fly sometimes. The long time fliers all warn not to go there, but it's more challenging flying, and great for working on your reflexes.

I was flying there yesterday in a northerly (we need some west to fly properly off the cliff), and noticed that we had some boundary layer turbulence about 10-12 meters off the ground, coming from wind shearing off the ridge on the side of the valley. I'm thinking that ridges are possibly easier to DS in, because they provide a longer and more predictable route to fly along while building speed in whichever layer you are accelerating in.

My last DIY plane is much faster than anything else I've built to date, not sure if I can get it doing anything halfway respectable though, it's only got corflute ailerons. got to start somewhere though !:)

#8 Zimodile May 07, 2010 02:29 PM

Guys can you help me understand road cut DS a little better? I think I understand the idea, but not 100% sure I have it right. Is the circuit kind of flat horizontal, out over the edge and back in again?

Would this kind of DS also be possible on a cliff i.e. with flat horizontal circuits? What's the best way?

Thanks for any help!

Z

#9 The Predator May 07, 2010 05:55 PM

I made this video:
Scratched (4 min 14 sec)
for Antonsoarer being so grateful for the AWESOME airfoil designs he created for me! Hope it help Zimodile. And yes you can DS cliffs just the way you think but, in general the best time to do it, in my experiences, was using a light wind otherwise the shear tends to lean to far over leaving you with only a small wedge of calm air or no shear at all as wind speeds increase. . . opps!

#10 gizzo May 07, 2010 06:13 PM

heres a vid of Dave and I DSing our local carpark, as described earlier.
the name of the game (3 min 36 sec)

#11 Zimodile May 07, 2010 06:18 PM

Thanks for those videos guys. I love the phrase "Dsing my local car park" - that's awesome! And top work on the videography both time - DSing and scratching tracks together twice in one evening - yeah baby!

Z

#12 Sleedo May 07, 2010 07:14 PM

Truro High Head DS 10-16-09 (2 min 26 sec)


My experience DSing in Cape Cod, light wind works best as Karl mentioned above as the shear disappears and there is too much wrap around from the sides in stronger conditions. Knap of the earth flying is always exciting even if the top speeds are nothing to brag about. ;)

EB

#13 Zimodile May 08, 2010 11:49 AM

thanks man - thanks cool - show's how it works really nice in that vid.

Cheers

Z

#14 daybyter May 09, 2010 10:43 AM

Great videos! Thanks for sharing! I guess over here, you'd be arrested after 5 mins when you try to fly at such a site... :(

#15 gizzo May 09, 2010 06:22 PM

Quote:

Originally Posted by Sleedo (Post 15036882)
http://vimeo.com/7137049

My experience DSing in Cape Cod, light wind works best as Karl mentioned above as the shear disappears and there is too much wrap around from the sides in stronger conditions. Knap of the earth flying is always exciting even if the top speeds are nothing to brag about. ;)

EB

How high is the front of the dune? I've tried a similar looking site with very limited success.
Cheers


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