Wednesday, 24 February 2016

Algebra 3m update - and Wolstonbury delivers again!

Well I just got back from Wolstonbury Hill - I love that place! 

You may have spotted a shout I put up last week, saying I'd maidened that Algebra 3m I built last year. It went very well, but I pranged it a bit on landing - the wind was a bit gusty and blowing 15kts +, with no ailerons, roll control is achieved as a secondary effect of yaw - which means there's a short delay between adding rudder and seeing any roll. The gusty conditions meant that I was unable to lift the wing which dropped and the tip hit the ground.

Now, when I bult the Algebra, Tim Hampshire advised me to add dihedral braces to the outer wing panels rather than the simple glue-joint + linen tape along the bottom. Of course, I ignored this entirely!

To be fair, I really wanted to build the plane as-per plans, to be as original as possible. I think if I had just been flying from a flat field the issue might not have arisen. But flying from the slope, I inevitably dug-in a wingtip and the joint was strained - it didn't break, but definitely deformed!

Solution? I retro-fitted dihedral braces... 

This afternoon I trekked up to Wolsonbury Hill - with a NE'ly forecast at 5 -6 kts I was keen to try the Algebra under conditons to which it was more suited.

The wind was very light indeed and I was quite reticent about throwing the model! However, I eventually plucked up the courage and committed aviation. The model scratched around for a few minutes, neither losing nor gaining height. I used the time to trim the model further and got it flying nicely. The spoilers proved themselves very effective on landing.

I walked a little further round the bowl and tried again. This time the breeze picked up slightly and the model was away! It climbed slowly and steadily to about 300ft, seemingly on the top of the wave of lift over the hill. There it stayed for the next 55 minutes! 

It was utterly peaceful up there today - the breeze was almost non-existent, the skylarks were trilling. I could hear the sheep baa-ing in the valley below, the occasional moo from the cattle.

Absolutely idyllic. The Algebra 3m really showed it can climb in the slightest lift... an epic afternoon and the ideal way to relax after an 0400 start and driving in London all day!

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