A ski-modified U.S. Air Force C-47 piloted by Lieutenant Colonel Joseph O. Fletcher of Oklahoma and Lieutenant Colonel William P. Benedict of California is among the first aircraft to land on the North Pole. A moment later, Fletcher climbed out of the plane and walked to the exact geographic North Pole, probably the first person in history to do so. In the early 20th century, American explorers Robert Peary and Dr. Frederick Cook, both claiming to have separately reached the North Pole by land, publicly disputed each other’s claims. In 1911, Congress formally recognized Peary’s claim. In recent years, further studies of the conflicting claims suggest that neither expedition reached the exact North Pole, but that Peary came far closer, falling perhaps 30 miles short. In 1952, Lieutenant Colonel Fletcher was the first person to undisputedly stand on the North Pole. Standing alongside Fletcher on the top of the world was Dr. Albert P. Crary, a scientist who in 1961 traveled to the South Pole by motorized vehicle, becoming the first person in history to have stood on both poles.