Since they are also designed to operate at very high speeds (typically hypersonic), conventional kerosene combustion reaches a limit, producing exhaust gases mainly consisting of carbon dioxide (CO₂) and water vapor (H₂O).
Under these conditions, magnesium can take advantage of these “waste gases” and burn vigorously when injected, creating extra thrust using energy that would otherwise be wasted.
Using magnesium to boost scramjets
The new afterburner injects the magnesium powder downstream into these hot gases (around 2780.6°F, or 1527°C). This results in secondary combustion, where the magnesium reacts with the water vapor and CO₂ to produce more heat and thrust.