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How low can you go?

06/09/2009

Permalink 11:16:01, by admin Email , 683 words   English (ZA)
Categories: solo, circuits & landings, cross-country, ASW 20

Unfortunately, but due to time constraints I just can't keep this blog up to date as often I would like. Too much to do, too little time, and all that. :(

Today was a day of a few firsts and even more lessons learned.

Aero-towing

For starters, today was going to be my very first aerotow in the new ASW20. The wind was a light SW and a little cross from the left of the runway. Now aerotows with the 20 are quite a bit more involved than those on the less high performance gliders to which I am accustomed to flying. The aerolons are not that effective at low speed and even less so with a cross wind so keeping the wings level is apparently tricky.

So the procedure is to start off in first negative flaps (flaps 2) and with the airbrakes out. This all helps by giving more airflow over the aerolon control surfaces and helps to keep the wings level. Well as this was my first go at it, the instructor told me to leave the airbrakes closed and locked and only to start in flaps 2 and shift back to flaps 3 (neutral) just before the plane starts to fly (like 50 - 60 kph).

Well it didn't go all according to plan and I let the wind pickup the upwind wing and I proceeded to drag the right wing on the ground for some distance behind the tug. As I was still keeping straight behind the tug and felt in control I road this out until full left stick eventually got the wings level. The rest of the tow was pretty uneventful and I was pleasantly surprised just how light and responsive the controls were behind the tug. I landed on 26 and waited for my next turn.

She has legs

LowFor my second flight, later that day, the instructor announces to me that he is going to ask the tug pilot to tow me to the Lady Slipper mountain where I should be able to soar the front slope using ridge lift. The only problem is that I have never flown so far away from our airfield before (in a glider) and I was pretty (well, very) unprepared for the flight

The aerotow went off better (again I started with the airbrakes closed) but this time I dropped the into wind wing slightly as I was pushing the stick over to keep that wing down and was still pushing when the wing-runner let go.

Anyway it was a pleasant 9 minute tow to the ridge where I released at 3400 feet with the instruction to return at no lower than 2000 feet. Ja well. Sounds easy enough hey. So I drift from high up along the ridge and found no lift. I mentally calculated the point to make my U-turn and got rather a nasty surprise once I was looking back from where I had flown. I was a LOT further down the ridge than I had expected. So now I'm getting a little worried. I head closer for the rocks but still find no lift and I round the furrest point at about 1700 feet (300 less than required). I radio base that I'm concerned about making 14 km return trip with only 1700 feet and they come back and say that because of the light tailwind I should make it.

It needs to be noted here that for the next 12km of this journey there are no outlanding possibilities! So I bring the speed back to about 110 kph (perhaps 20 kph above best glide), keep the string straight and head direct for the airfield (shortest possible route). Needless to say it was rather a long trip and a little bit stressful but at about halfway I felt confident that I would make the airfield, which I did, crossing the upwind fence at 300 feet, just enough for a short circuit. Fortunately there was so sink along the way and the tailwind also helped a bit.

Oh well, tons of stuff learned here, mostly (1) plan the flight properly and (2) the 20 can fly pretty darn far when needed. Cost, two aerotows and some 20 time.