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Wind turbies and spring flying tips

Ed Cleasby - 22/04/2004

Mr Angry of Bentham

I don’t know whether you have heard about the proposal for a new wind farm on the fells between Shap and the Howgills but it has been in the local and national press during the last six months. The area to be covered is six kms of unspoilt ridge behind the Whinfell flying site and runs between the A6 road leading to Shap and the Motorway at Tebay. The proposal is for twenty six turbines each to be a staggering one hundred and twenty six meters in height. This is higher than the Blackpool tower, which can be seen from fifty miles on a clear day. The thought of this visual scar on such a beautiful and quiet landscape is truly depressing, the view from Whitestones would be ruined forever. The effect on free flight will be to create a meaningful hazard to any XC flights leaving the lakes via the Whinfell range. There is an opposition campaign in progress that is aiming to force the issue to a public enquiry. However pressure is still required from those who object and the place for that is your local MP.
What we are seeing here is the thin end of a very thick wedge regarding renewable power supplies. The Government is committed to a target of ten percent of national supplies within ten years or so and this application is an indication of what is to come. The power companies have no regard whatsoever for the visual or environmental consequences of turbines and their agenda is based purely on profit and keeping the Government ministers happy. I believe that we must fight to prevent these developments gaining an acceptance within the Lakes because if we don’t the whole of the National Park and its environs will be surrounded with a ring of steel and carbon. The thought of living with these monsters and having to dodge around them on any flight out of the Lakes not much of a prospect to look forward to. We are currently the number one target area for wind turbines and with a small population we will be quickly overwhelmed by the power and money of the developers and energy ministers. The time to speak up is now, in two years it will be all over and a done deal. I urge you to write to your MP expressing your opposition to the siting of these industrial machines in a rural landscape. The proper place for these turbines is out at sea where they are least intrusive.

Seasonal flying tips
Have you ever sat at take off and wondered just how strong and bumpy those spring thermals really are? Or have you tried to fly on a nil wind day with only thermals to keep you aloft? Well I have some ideas for you to try that you may not have considered before.
What I try to do before I commit my fragile body to the great washing machine in the sky is to measure the upward speed of thermals passing over the hillside upon which I am sat. I do this in order to ascertain the strength of the conditions aloft. I think that this is of more use than the average wind speed on a given day. The way to do it is to use an anemometer to measure two things, firstly the background wind strength and then the amount that it increases by when a thermal comes through. For example, you measure an average wind speed of ten mph but this increases to twenty mph in the thermal cycles. You can then convert this extra increase to knots or meters per sec and consider this in terms of thermal strength ie a five m/sec thermal which would be a strong climb for this country. The rate that the wind increases as the thermal passes through will also indicate how rough the conditions will be. A very fast rise in the gust speed and a short thermal time span will show active conditions. If this is coupled to strong thermals then it will be rough aloft. Other good indicators are soaring birds, they can be seen to be thrown around in bumpy air and I always have a healthy respect for these sort of days.
When I was a beginner I always marvelled at the way the pros always seemed to get up and away on nil wind days while I always ended up at the bottom of the hill. What I have now realised is that they were able to feel when to launch and I have learnt some of the following lessons.
On nil wind days I will sit and wait until the thermals coming up the hill at least equal the sink rate of my glider. There is little point launching until this time because you will not be able to maintain your take off altitude. As soon as the thermal speed exceeds my min sink I know that I should be able to climb out provided I have the skills to find and stay in the lift. Again the length of the thermal gust will indicate the size of the thermal. A rapid gust lasting a couple of minutes is a very small thermal that will be hard to stay in. One that lasts ten minutes will be much more useable. The frequency of the thermal gusts will also indicate how many thermals there are coming up the slope. Regular gusts will mean that you should be able to climb or at least maintain. Infrequent gusts mean that you should top land as soon as you fall out of the lift because you will have sunk out by the time the next one arrives.
So to conclude, spend some time sat at take off facing the breeze just feeling the conditions. Measure what is happening, observe the wildlife. Watch the pitch and roll of people who may already be aloft. Consider what you will be expecting once airborne and think about the best time to launch. Have you the skills and experience to cope or get the best from the day or should you watch and wait until things would suit you better.

Have fun and fly well.

Andy Plimmer.

 

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