This is an F-82F Twin Mustang long-range fighter, and it really did look like this. Effectively two P-51 Mustangs bolted together (only apparently the USAF couldn’t do math), the F-82F wasn’t ready during the Second World War, but it did see service in the Korean War before the rapid advancements in jet engine technology ended its career. This excellent Lego recreation of one of America’s weirder aircraft comes from John Lamarck and there’s more to see on both Flickr and MOCpages. Click the links to view the full photo set, and for more double horse goodness click this secret link.
Double Horse Goodness