section_path: Types/Heat engine/Air-breathing combustion engines
section_name: Air-breathing combustion engines
paragraph_text: Air-breathing combustion engines
  
  Air-breathing combustion engines are combustion engines that use the oxygen in atmospheric air to oxidise ('burn') the fuel, rather than carrying an oxidiser, as in a rocket. Theoretically, this should result in a better specific impulse than for rocket engines.
  
  A continuous stream of air flows through the air-breathing engine. This air is compressed, mixed with fuel, ignited and expelled as the exhaust gas. In reaction engines, the majority of the combustion energy (heat) exits the engine as exhaust gas, which provides thrust directly.
  
  Typical air-breathing engines include: