Steam Powered Aircraft: An Aeronautical Engineering Impossibility?

Even though mid 19^th Century accounts of their flight attempts are notable for their “comical failure” are those steam powered aircraft still an aeronautical engineering impossibility in the 21^st Century?

By: Ringo Bones 

Maybe we should be “blaming” the Mythbusters for doing those proof of concept experiments in their shows – especially ones pertaining to “aeronautical engineering impossibilities” – like the lead balloon and the concrete glider, which more or less, they managed to successfully flew on their shows and confirming them that they are not an aeronautical engineering impossibility after all. But has the Mythbusters ever tried to build and fly a steam powered aircraft? After all, if one managed to successfully fly back around 1850, the Wright brothers would probably have given up designing and building their first successful gasoline-powered aircraft. 

The steam powered aircraft gained legendary status probably because the press-at-large became very intrigued by William Samuel Henson’s publication of the design of his “Aerial Steam Carriage” back in 1843 after it was patented in 1842. Although a full-sized model was never built, illustrations of this “remarkable aircraft” were given world wide publicity and did more than anything else to establish the modern airplane configuration of fixed monoplane wings, a fuselage, a tail unit, and propulsive airscrews – features that became standard in many airplanes some 65 years later. 

Another intriguing possibility that a steam powered aircraft – like William Samuel Henson’s Aerial Steam Carriage and those like it – could have successfully flown back in the middle of the 19^th Century is that Henson hired a very skilled mechanic named John Stringfellow to design and build an extremely light steam engine that could have flown the first ever steam powered airplane. Stringfrllow’s steam engine achieved a power-to-weight ratio of around 20 pounds of engine weight per horsepower produced – which was comparable to the power-to-weight ratio of the engine used by the Wright brothers during their first ever successful flight. Sadly, neither Henson nor Stringfellow managed to design a propeller that is as efficient as the one designed by the Wright brothers in converting mechanical rotation into forward thrust – i.e. the Wright brothers’ propeller has a 66-percent efficiency rating. Given that today’s modern propeller designs can now achieve 90-percent efficiency, will the Mythbusters or any other daring aeronautical engineer be building their own flyable steam powered aircraft anytime soon?