https://en.wikipedia.org/wiki/Richard_E._Byrd#1926_North_Pole_flight wrote:
<<Rear Admiral Richard Evelyn Byrd Jr., USN (October 25, 1888 – March 11, 1957) was an American naval officer and explorer. On May 9, 1926, Byrd and Navy Chief Aviation Pilot Floyd Bennett attempted a flight over the North Pole in a Fokker F.VIIa/3m Tri-motor monoplane named Josephine Ford, after the daughter of Ford Motor Company president Edsel Ford, who helped finance the expedition. The flight went from Spitsbergen and back to its take-off airfield, lasting fifteen hours and fifty-seven minutes (including 13 minutes of circling the pole). Byrd and Bennett claimed to have reached the pole, a distance of 1,535 miles.
When he returned to the United States from the Arctic, Byrd became a national hero. Congress passed a special act on December 21, 1926, promoting him to the rank of commander and awarding both him and Floyd Bennett the Medal of Honor. Bennett was promoted to the warrant officer rank of Machinist. Byrd and Bennett were presented with Tiffany Cross versions of the Medal of Honor on March 5, 1927, at the White House by President Calvin Coolidge. The widespread acclaim from the flight enabled Byrd to secure funding for the subsequent attempt to fly over the South Pole.
Since 1926, there have been doubts raised, defenses made, and heated controversy over whether or not Byrd actually reached the North Pole. In 1958, Norwegian-American aviator and explorer Bernt Balchen cast doubt on Byrd's claim on the basis of his knowledge of the airplane's speed. Balchen claimed that Bennett had confessed to him months after the flight that he and Byrd had not reached the pole.
The 1996 release of Byrd's diary of the May 9, 1926, flight revealed erased (but still legible) sextant sights that sharply differ with Byrd's later June 22 typewritten official report to the National Geographic Society. Byrd took a sextant reading of the Sun at 7:07:10 GCT. His erased diary record shows the apparent (observed) solar altitude to have been 19°25'30", while his later official typescript reports the same 7:07:10 apparent solar altitude to have been 18°18'18". On the basis of this and other data in the diary, Dennis Rawlins concluded that Byrd steered accurately, and flew about eighty percent of the distance to the Pole before turning back because of an engine oil leak, but later falsified his official report to support his claim of reaching the pole.
Accepting that the conflicting data in the typed report's flight times indeed require both northward and southward ground speeds greater than the flight's eighty-five mph airspeed, a Byrd defender posits a westerly-moving anti-cyclone that tailwind-boosted Byrd's ground speed on both outward and inward legs, allowing the distance claimed to be covered in the time claimed (the theory is based on rejecting handwritten sextant data in favor of typewritten alleged dead-reckoning data). This suggestion has been challenged by Dennis Rawlins who adds that the sextant data in the long unavailable original official typewritten report are all expressed to 1", a precision not possible on Navy sextants of 1926 and not the precision of the sextant data in Byrd's diary for 1925 or the 1926 flight, which was normal (half or quarter of a minute of arc).[
If Byrd and Bennett did not reach the North Pole, then the first flight over the Pole occurred a few days later, on May 12, 1926, with the flight of the airship Norge that flew from Spitsbergen to Alaska nonstop with its crew of Roald Amundsen, Umberto Nobile, Oscar Wisting, and others. Amundsen and Wisting had both been members of the first expedition to reach the South Pole in December 1911.>>