It's easy to see from this photo where aeroplane designers got their inspiration from. This smart male (drake) eider is coming in to land and using his tail and webbed feet to slow down!
Eiders breed around the coasts of Scotland and northern England, but move further afield in winter. During the breeding season, the females use their own feathers to make a cosy nest lining (which is where eiderdown comes from) and the males make a funny cooing sound.
You can hear it and read more on our page.
This image is just one of thousands you can browse on RSPB Images - have a look!
Looks like Concorde coming in to land...
Pat Adams - Flickr - BLOG