Riding on Air

Why is a Tornado like a gannet? The first is an RAF combat aircraft, while a gannet is a bird that dives vertically for.fish. The answer? Well, both are designed to kill-and both use variable-geometry wings. Birds and aeroplanes ride the air by the same rules, but how far do the similarities go? Aircraft sometimes stall dangerously - but do birds? Why do some birds fly in ' V' formations? And how have birds' wings made flying safer for everybody?