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\title{BBC-Future AMA: I'm Professor Michael Smart, chair of hypersonic
propulsion at the University of Queensland, Australia. I'm here to
answer questions about hypersonic travel. AMA!}



\author[1]{Prof_Michael_Smart }%
\author[1]{r/Science AMAs}%
\affil[1]{Affiliation not available}%


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  \date{April 24, 2026}


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\begin{abstract}
I spent 10 years at NASA's Langley Research Center designing hypersonic
engines called scramjets. Scramjets are airbreathing engines (similar to
a jet) and enable aircraft-like flight at speeds above Mach 5. At UQ, we
flew our own scramjets as part of HyShot, and we are now involved in
Hypersonic flights with DST and the US Air Force as part of the HIFiRE
Program. From a young age I have always been interested in space travel.
The Apollo program and the Space Shuttle really inspired me. However,
these launch systems were very wasteful, with over 95\% of the take-off
mass of Apollo being thrown away on each flight. Almost all current
rocket-based space launch systems are the same. Scramjets could help
make space launch re-usable. Since 2006, I have been trying to find the
best way to do this. What my research group has come up with is called
SPARTAN. It uses a scramjet-powered plane as the second stage of a space
launch system for small satellites. I received the 2012 International
Congress for Aeronatics (ICAS) Von Karman Award for International
Co-operation in Aeronautics. I'll be talking about hypersonic travel at
BBC Future's World Changing Ideas Summit on 15 November in Sydney. I am
happy to answer any questions on hypersonic flight and scramjets from
16:00pm EST, 21:00pm GMT. Ask me anything! Signing out now - great
comments and conversation. I will check back in later to answer more
questions. Cheers!%
\end{abstract}%



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