100 years ago....
The first helicopter flight has lift off
Feb 18, 1921
A French engineer has managed to achieve true flight in a helicopter, and claims to have solved the problem off how to match power and weight in the machines.
Other pioneers have succeeded in getting their machines to hover a few inches off the ground using massive motors, but every time they tried to get higher the weight of the machine and its engine drove them back. Now Etienne Oehmichen has told the French Academy of Science that he has managed flight using just a 25 hp motor attached to a simple structure weighing a total of only 100 kilos.
He estimates rotors only need eight-and-a-half horsepower to lift 135 kilos. However, he has yet to discover the important trick of how to keep a helicopter stable.
Article from "Chronicle of the 20th Century" ISBN 1 872031 80 3