Military helicopter to fight fires...
There are several legal and constitutional issues with military helicopters being used for fire fighting (even if it seems like common sense). First, the Defense Department doesn't have that mission assigned. That means that military pilots are not funded for that mission; therefore, they aren't trained for that mission. Second, most pilots have a priority mission already (i.e. in some kind of rotation to overseas forward areas in Iraq, Afganistan, etc). Thirdly, only the National Guard can be called on by the Governor of the State to provide this type of assistance. I doubt the Aviation Brigades in the National Guard have many aircraft of that type capable of this task anyway. Federal troops can only be used if Martial Law is declared under some kind of Federal emergency. Here is a summary between National Guard and Reserves/Active Military; I hope this makes sense (and why it's important)...
Army National Guard - These are State militia, and the commanding general is actually the Governor of the state. As a State militia, they are the ONLY military folks that have the consitutional ability to use police powers with cilivians (except Coast Guard). The bottom line is, in case of civil unrest or State emergency, these are the ONLY folks that can provide humanitarian assitance or to engage civilians with any kind of force (Posse Comitatus). In addition, they are also part of the National Command Authority's security plans for defense and combat support.
Army Reserves/Active Army - These are Federal troops, and the Reservists are designated as "on-call" to augment the Active component. The constitution PROHIBITS federal troops from ANY civil or police action whatsoever (Posse Comitatus). The only exception is if a Federal emergency is declared and Martial law is SPECIFICALLY implemented. An example would be when Hurricane Andrew hit Florida several years ago. After weeks of trouble with looters and badly needed logistical and medical support, Federal soldiers were temporarily given these powers and that portion of the State was under Martial law (that means even the Governor had no power in that area). In history, this has happened very few times. Usually everything you hear and see on TV is the National Guard. Generally, Reservists are activated to supported the Regular Army (i.e. go and help in Iraq).