He was a founding member of the American Rocket Society, serving as both president and editor.
Manning retired from the American Rocket Society in the mid-1940s, stating that rocketry had 'grown up', and was no longer a place for amateurs.
For perspective, look back thirty-five years to 1930 - the American Rocket Society had not yet been founded then.
Its name was changed to American Rocket Society on April 6, 1934.
The Journal of the American Rocket Society was published from 1945-1953.
The concept was introduced in 1954, before the dawn of human spaceflight, to be displayed at the annual conference of the American Rocket Society.
Finally, in 1960, the American Rocket Society reviewed his patents and acknowledged him as the inventor of the jet engine.
He was president of the American Rocket Society and wrote more than 50 technical articles.
He was a member of the American Rocket Society.