Before Dec. 1906 the Wright brothers were able to sustain 62 pounds/HP, in 1908 only 35 pounds/HP
According to the Scientific American from Dec. 15, 1906 (see 1), the Wright brothers' planes were capable to fly at 38 mph with only 1 HP for each 62 pounds of their weight. I have to repeat that, in Dec. 1906 the flights of the two brothers were no more than claims.
In Dec. 1908, when the airplanes of the two US inventors were already a reality, the french journal L'Aerophile (see 2) gave a detailed description of the flying machine W. Wright had flown in the preceding months, saying, amongst other things, that the plane weighted bout 400 kg (881.85 pounds) and had an engine developing 25 HP, which means that the aeroplane weight to power ration was about 35 pounds/HP, much worse than it was achieved before Dec. 1906.
Again, another lie of the Wright brothers, that 62 pounds/HP at 38 mph was not a realistic figure, they could not have achieved such a performance before Dec. 1906 as long as about two years later their flying machines were considerably less capable sustaining just 35 pounds/HP.
1) "
At 38 miles an hour, they (the Wright brothers) were able to sustain 62 pounds per horse-power"
"Genesis of the first Successful aeroplane", Scientific American Volume 95, Number 24, pag. 442,
December 15, 1906,
https://archive.org/stream/scientifi.../search/wright
2) "
L'aéroplane complet pèse environ 400 kilogs. ... Le moteur, du poids de 90 kilos, développe 25 chevaux à 1.400 tours ... une vitesse de 55 kilomètres à l'heure au bout du rail."
L'Aerophile, pag. 471 - 474,
December 1, 1908,
http://gallica.bnf.fr/ark:/12148/bpt...20m/f481.image