Two French aviators have been officially honoured with Paris street signs saying they did complete a flight across the Atlantic from east to west.
They made their attempt just before American airman Charles Lindbergh, who made the first solo flight 12 days later, but in the opposite direction.
Charles Nungesser and Francois Coli disappeared on board their biplane called The White Bird in May 1927.
The duo – seen as heroes in France – were flying from Paris to New York.
The exact location of their crash has never been discovered.
But officials in Paris have unveiled new street signs bearing the names of Nungesser and Coli which accept the theory that the pair succeeded in their trans-Atlantic quest.
The BBC’s Huge Schofield in Paris says that the theory is far from proven.
Today the strongest argument in France is that the plane came down near the French territory of St Pierre et Miquelon, which is just off Newfoundland in Canada.
Officials in Paris insist they are not trying to undermine Lindberg’s achievement by updating signs in the city that previously stated the pair disappeared while crossing the north Atlantic in 1927 to stating unambiguously that they “crossed the Atlantic” on the 8 and 9 May.
A researcher claims to have found telegrams from the US coastguard, dated a few weeks later, detailing the discovery of white biplane wings and speculating that they may be from The White Bird.
There is even a suggestion the plane might have been shot down by the US coastguard, who at that time of prohibition were on the lookout for alcohol smugglers.
But our correspondent says that until an actual part of The White Bird is discovered, no-one will ever know for sure.