What is The World's Fastest Bird

People will always argue about this. Most think that the pelregrine falcon is the fastest bird by far but when it's speed was currently measured the maximum in level flight was 96 kph (58 mph). Measurements by radar show that eider ducks fly for long periods at 75 kph (45 mph) but the world record is held by the Asian spinetailed swift, which has been time at 170 kph (102 mph) in level flight.

img credits: http://listtoday.org/amazing-birds-of-prey-6-cool-hd-wallpaper.html