fire bomber
/ˈfʌɪə ˌbɒmə/noun
1An aircraft equipped to drop water or other substances onto a fire as a firefighting measure. Also occasionally: a member of the crew of such an aircraft.
2A person who throws a fire bomb; one who attacks or destroys with fire bombs.
Origin
1930s; earliest use found in Rapid City (Manitoba) Reporter. From fire + bomber.