WIND FRUSTRATIONS

[thevon]

Today I (wrongly) thought the weather report (both BOM and Seabreeze) looked very promising for a strong SSW easing in the arvo. So after working up late I squeezed a gap between some appointments today and bolted for Dayboro, in the hope that I might raise my PB with some thunderclappin' DS with the Wizard.

Sean decided to come too. I got worried that the wind wasn't too strong on the way and rang Sean again but he said he was still coming. So I pressed on. At Lemontrees I DS'ed on the "hump" and it was OK but not great, and was working in the opposite way to normal. So I went up onto the Lemontree ridge and DSed the Bat a bit but it was flukey so I bailed and called Sean (who was still on the way) and we met at Kevs Ridge (about 20mins away).

When Sean arrived he saw my Bat descending in sink to the bottom of the hill! Cursing and a long walk ensued. The wind was patchy and dropping out and we basically ended up thermalling. There were regular big thermals passing through so we basically waited for them to come, gained some height and did some DSing when the wind picked up after the thermals passed over. This meant short flights with lots of emergency landings. There were several 10min patches of good air and for a while I was doing nice DS figure 8’s. But mostly it was too light and too much from the right. We left when the wind dropped out completely and we could actually feel it blowing across the slope from the north-west!
Darn weather report. Rather than a strong SSW, it was more like a weak SW to WSW. Bummer! I’m giving up on that site. It’s very rarely any good. No PB’s today. Next time.

But gee I was impressed with Sean's Erwin, and his skill flying it. At one point he did a bad throw, lost height and went into sink and didn't panic, circled way out, long way below, and finally worked it back up again. The Erwin flies ... well, something special I think.

[sean]

Yep, bit of a fizzer as far as flying is concerned but we can't complain, it was a beautiful day to be outside. I was lucky getting the Erwin out of that sink - I've done the same thing a number of times before and ended up doing a long walk!

[thevon]

A strong NW to W was forecast for this arvo so after preparing last night and starting early to get things under control, (and my gracious wife being willing to handle this arvo’s jobs), I got away after lunch but not without some concern about the weak breeze which actually turned E at home before I left! But I trusted the BOM and was also reassured hearing a “Damaging wind warning” on the radio in the car!

Arriving at Bald Knob the strong NW wind got the pulse racing. It felt like a wind tunnel at the bottom gate. Up top I was quick to launch the Bat which began whistling around the top gate DS circuit at a frightening pace. My dumb thumbs combined with the turbulence made most of the area a dangerous place to be, but it was wild fun. My mate Greg turned up to watch – I threw out the Reaper and he gunned it at 95mph, but it felt much faster – probably because the best line at the gate involves coming up very low over the top, between a small tree and the fence, so it’s really in your face stuff. It was really exciting and reminded me of the big days flying at the gate last year when we were total DS novices. Then coming back up the hill the Reaper dipped low and I ran out of elevator and it went into a soft tree, but did some damage which I set about repairing just as Sean arrived. He got the Bird out and was doing big circles, way back and judging by the tail waggling it wasn’t smooth.

I got the Reaper back in the air and Sean and I took turns in the circuit until he yelled that it wasn’t working. I tried to prove him wrong with the Reaper, being game to go lower with the foamie but it repeatedly went sloppy and lost response over the back, and fluttered down. He was right. The wind seemed to have gone too North.

So I ventured over to the Hump ridge, wondering if it would work in reverse. Sean has tried the same thing before with no luck, and I had the same result … breaking the snappable joiner on the Reaper tail boom. Tried the Bat too and it was frustrating to have huge lift, great height for a dive-in, a nice sharp long ridge apparently cross-wind, but no DS effect. The trees and grass over the backside were all blowing around so it was no wonder it didn’t work. But how the wind could swing around the back of that ridge I just don’t understand. Theoretically it looks perfect, but in practice it’s hopeless (in a NNW).

I was optimistic as the BOM and Seabreeze showed the wind swinging W as it strengthened, so I thought you bewdy, it’s gonna come good soon. The wind was picking up strongly but the lift out front was a bit rumbly. I tried DSing the gate again and kept losing speed and dropping onto the back. Sean warned me “stop trying, it’s just going to keep doing that” just as it crashed again and the tailboom splintered completely off this time. Ho-hum. The plane was flying into an enormous tailwind down the back and losing airspeed, hence the result.

We were both pretty glum. There was heaps of wind, it felt like it was coming from the right direction up the slope, there was plenty of lift (though rolly-poly) but it was dead duck DS. To add to our woes the sun was blinding us badly and we had to hold the radios up to block it out.

I decided to give the Wizard a go on the front despite the sun. It had its 640gm ballast stick in and flew flawlessly. Nice and responsive. I spent some time with Sean dialing in the flap/ elevator compensation to get the landings nicer, and generally mucking around. A couple of times the wind felt more West so we manoevred back over to the gate and dived in but it obviously wasn’t working. I had an adrenaline shot when it did a spontaneous ¼ roll and dive on the way back up! Nasty turbulence and tailwind rotor.

On one nice landing Sean said “watch out for the road” but I was a bit lower down the curve of the hill and thought I’d cleared it, and thunk, the Wiz bellied out hard on the road. There were no marks but one of the HS65HB servos for the V-tail had stripped. I thought they were tougher than that. Anyway we said goodbye, Sean headed home and I started to pack up.

By now the wind was so strong that it was hard to pack up the Wizard etc as things were blowing everywhere and I had to hide behind the car to phone home. I couldn’t resist temptation so I put the Bat up again and tried to DS, but it was hard to hold a line. I had one last dabble, putting ballast in the Bat for the first time. It flew perfectly with the extra weight and carved thru the backside turbulence much more cleanly. I got a few quick laps working OK but then it was back to the bad air again so I finally quit. On the way back Sean SMS’ed that Seabreeze showed the wind had been N to NNW all arvo! No wonder it didn’t work.

It’s dysfunctional to be flying at the Knob on a brilliant warm winter day with plenty of frontside lift, and feeling as though it’s a wasted trip. We’re lucky to be able do such things; incredibly lucky. I think with our DS obsession we’ve chosen a terribly hard thing to do. So much has to be right for it to work well. Sean and I put in so much legwork and there are so many failed expeditions! Not to mention the above – average degree of damage to repair. I came home with a broken Reaper tail, bent Bat fin and the Wizard servo to replace. And that was a good day! But despite the many lows there are the times when it all comes together and when it does, the highs are stratospheric.

I’m just hangin’ out for the next one!

[Pij]

That was good reading, thanks Andrew. Would have been better to be there, though.

[sean]

The DS sites at Bald Knob are temperamental - the wind just needs to change direction by a few degrees and they just stop working. I was at the Camel Hump a week or so back and there was a strong wind blowing straight up the slope (due south), which is extremely rare. But the air was spilling around the hill from the west and causing there to be lots of moving air on the back, killing the DS effect and making it extremely turbulent. Ironically this means the Camel Hump really needs an SE to work, which means the air must be blowing up the slope at an angle, which kills the frontside lift! In the past we've been frustrated that the air never blows straight up the camel hump, but that seems to be a blessing not a curse...