Flox is a historic cryogenic oxidizer created by mixing liquid fluorine with liquid oxygen to increase the specific impulse of a rocket engine. While it significantly boosts performance compared to pure liquid oxygen, the extreme toxicity and corrosive nature of fluorine make it exceptionally dangerous to handle. The exhaust products are also highly toxic, limiting its practical use.
Heard on the job
The early test stand required extensive scrubbing systems because they were burning flox and RP-1.
Insider tip
Flox is typically followed by a number indicating the percentage of fluorine, such as Flox-30 for a 30 percent fluorine blend.