FAE meaning in Military and Defence ?

A thermobaric weapon, aerosol bomb, or vacuum bomb is a type of explosive that uses oxygen from the surrounding air to generate a high-temperature explosion. In practice, the blast wave typically produced by such a weapon is of a significantly longer duration than that produced by a conventional condensed explosive. The fuel–air explosive is one of the best-known types of thermobaric weapon.

Most conventional explosives consist of a fuel–oxidizer premix (black powder, for example, contains 25% fuel and 75% oxidizer), whereas thermobaric weapons are almost 100% fuel, so thermobaric weapons are significantly more energetic than conventional condensed explosives of equal weight. Their reliance on atmospheric oxygen makes them unsuitable for use under water, at high altitude, and in adverse weather. They are, however, considerably more destructive when used against field fortifications such as foxholes, tunnels, bunkers, and caves—partly due to the sustained blast wave and partly by consuming the oxygen inside.

Many types of thermobaric weapons can be fitted to hand-held launchers.