Frontside DS?

[thevon]

There's an "amateur DS junkie" thread on RC Groups which I've pitched into, and Ian (Daemon) suggested that with the lack of good close DS sites we should look for spots to do "frontside DS".

Here's the page, and have a look at the video link - very happy stuff.
www.rcgroups.com/forums/showthread.php?t=877878&page=7#post9978229

[Pij]

Funny you should mention that. I just came back from Elliott Heads, SE winds which changed between marginal and almost okay. The wind was not right on the slope, which means that as I 8'd along the slope, there was an upwind leg and a downwind leg. I got the best results by doing the upwind leg below the cliff height, very snug in to the edge, trying to give minimal inputs to avoid drag, to keep up speed. Then I'd pop up above the cliff height, further out from the edge, and sweep downwind, drop into the cliff edge, and head upwind again.

So I was thinking that what I was doing was something related to DS'ing, but couldn't be DS as it was frontside.

I did learn that, when there are trees on the frontside and you are flying well within branch height, you need your tree-retrieval pole handy. Repeatedly. And the rocks jump out to get you as you go past, too. Nothing a bit of tape can't fix, on the tips.

Just saw the video!
www.thud.us/videos/rc/zion-fishbowl-fun4-700k.wmv
Amazing!

I've just watched through the movie 5 times, once with each member of the family. My youngest son loved it so much he watched it every time, and now he's drawing a picture about combat wings.

The big differences between what they do on the movie, and what I tried today: I was practising to keep up kinetic energy in small conditions, while they had plenty of energy! I had trees and rocks, they had cars and rails. They are good, I am just trying. They were a group, I was alone. Also, I was doing an outward turn on the downwind end, then dropping in to the edge, which was washing off energy. I need to increase my aileron rates and dare to do an inward turn at the downwind end. Oh well, more things to practise.

[thevon]

Pij, don't be too hard on yourself - I reckon it's really hard getting any effect and consistency in those conditions. Also I wouldn't suggest increasing the aileron rates. If anything, you need to keep them low as more aggressive throws act like air brakes and slow you down. The big trick is to keep the plane banked steeply, so your turn is controlled largely by elevator, not by aileron. It's hard to do that when it's not classic, full circuit DS, but certainly at the bottom turn (in the dead air) you need the plane to be banked steeply and you pull up elevator to tighten the turn. When you do get a good DS situation your plane is usually better behaved with less aileron and more elevator than for normal flying - that's how we've been setting dual rates for DS.

[Pij]

Thanks Andrew. I might have to touch up the elevator rates a bit then. Today I increased my (low) aileron rates from 80 to 90%, which helped me pull my turn before the trees at the end of the downwind leg. It was just an instant of roll, then hard on the (low rates) elevator. But the extra aileron throw helped so I could leave the roll a moment later. I see your point about the elevator rates being the key. When I try the inward turn downwind, I'll need increased elevator to finish the turn and keep the glider off the wall. It should be fun. Need the SE winds back.

[drcuzo]

Andrew
What do think of the potential for frontside DS at Brandenburg Rd. The way the road is cut into the hill may have potential.
Steve

[thevon]

Definitely! We should keep an eye out for such spots. There must be quite a few, where you have a road cut into a steep hillside. We need to find places like that which face in the direction of regular winds, eg SE.

[Vanders]

Yeah that clip was so cool, it'd be great to have numerous planes scooting around like that.

[Pij]

Without traffic, preferably. And park further away.

What about a quarry?

[ezza]

I have a couple of spots that are good for frontside ds and it is quite amazing how a little change in windspeed or 'lift power' can add speed. Not amazing speed but a bit of a gain and enough to go round and round.

One is a hill where the slope drops at a gentle rate and then drops off steeper. As you fly out from the slope the lift is much stronger, further out over the steeper section. You can circle endlessly and get some pretty good speed(maybe 80mph with a nice glass ship), by doing a horizontal turn in this stronger lift, straight back at the slope and then do the bottom turn, back in the lighter lift just above the ground.

Another spot has a big tall row of trees at the top of the ridge. You can do a bottom turn down near the base of the trees and then a top turn out in the lift. Works great, and even works well for vertical loops.

I have been able to ds where there is a fairly sharp change in slope angle, relative to the wind direction. Minor effect but still works.

I have also found moments of frontside ds'ability on a normal frontside slope. You know when a thermal comes through on the front and all of the sudden the wind goes still where you are standing at the top of the slope? You can usually squeeze a few laps in before the wind returns. Bottom turn right where you are standing and head back out until your plane hits the lift and turn straight back at yourself.

Really helps to have a clean and efficient model. Atleast a wrinkle free foamy or even better with glass. Hope you guys find some fun grooves.

There is a video called Endless Lift 3 that has a little section showing and explaining frontside ds.

Eric

[callun]

I wonder if Pedwell Road would be any good...

[thevon]

Great tips Ezza. Regarding the hill with the gentle lift on top and stronger out further, I'm pretty sure Mt Coolum would do that. Will have to try. From the peak, if you fly out to the S, there'a a 1-200m roundish top with gentle lift, then it bangs up as you fly out over the big vertical cliff. We were to trying to find gullies with dead air, but didn't get it to work at all. Should have tried the frontside stuff.

Pedwell Rd ... Callun, yes I thought the same as the lift there is huge. You can definitely DS at the top with something light, but that's backside DS. However for frontside DS I was wondering about that house site, lower down to the right towards the power line. It's cut into the hill and I think the air is pretty dead there, but it's not very big. Also you're very likely to prang into the shipping container or old 4WD's that are parked there! Either way we need to check it out!