In my last post I had left aluminium gliders on one side and made paper deltas, basing their layout on Suzanne – a world record holder for gliders made from a folded A4 sheet.
Now I have made the logical next step: deltas from an aluminium can.
I cut the aluminium sheet from the can and straightened it using my usual method.
The first one set the parameters. 150mm long 100mm or so span, and the aft-most 40mm rectangular. The diagram below is for the second model (see below), but the general layout was similar for them both. The light grey at the top is a rectangular tube with joining pieces – to strengthen the front when it lands heavily. I used it to hold the ballast.
I made tabs on the top of the fuselage so I could stick it to the wing with sticky tape.
It took a lot of fiddling, but I got it to fly in the end.
Originally I tried to fly it with the flat wing that I used previously
with the paper models, but that didn’t work, so I bent the outer 20mm or so of the wing up and made two cuts (like dressmakers darts or sailmakers overlaps) so I could bend the aft 40mm in an upward curve to follow the shape I cut in the top of the ‘fuselage’ (see it more clearly in the photo of the mark 2 glider below).
With the rubbish first trials it didn’t look like flying at all. But after I bent the outer section of the wing up and made the cuts, I could control the curve in the centre-line of the wing. By adjusting that curve and the ballast on the nose I got it to fly tolerably well.
The next step was to see if I could make one that would fly ‘straight from the box’. I held it together with glue this time.
I got close, but all the adjustments are so subtle and don’t seem to stay set for very long, so I still had some fiddling to do.
I used a launcher for consistency. In the end I got one flight of almost 30m. It was down a slight slope (1:15), but was most encouraging.
Next I’ll try it in an open space, not the street outside our house.
RhymeAndReason 