I had a word with the Sparrows, breakfasting at the bottom of my garden this morning, and they all agreed that the most significant advance in flight was, in their opinion, the ability to flap their wings.
I couldn't argue with that...

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LOL...

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Paul....(being silly again..)...

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Win 8.1 64-bit. DX11. Advent Tower. Intel i7-3770 3.9 GHz 8-core. 8 GB System RAM. AMD Radeon HD 7700 1GB RAM. DVD ROM. 2 Terra Byte SATA Hard Drive. Philips 17" LCD Monitor. Saitek Cyborg X Fly-5 Joystick. ...and a Briggs and Stratton Petrol Lawn Mower.