There are two verb tense errors in this paragraph. Correct them:
Indeed, whilst the Chinese allegedly strapped prisoners onto kites in the sixth century, and Elmer of Malmesbury was recorded as having glided for more than an eighth of a mile before crashing and breaking both his legs, it was not until the start of the 1900s that scientific attempts are made to get a man off the ground under his own steam. These bicycles-on-wheels might seem comical to today’s aeronauts, but in 1912 they are good enough to help Gabriel Poulain scoop a prize of 10,000 francs, having allegedly flown his contraption more than a metre off the ground for distance of 10 metres.