Make regular checks on the outside view to check your engines; if your co-pilot
has been hit you don't get any warning. Fuel leaks can be critical to the success
of a mission. If necessary you need to turn off an engine or two and drop out of
formation to conserve fuel. If your engines are on fire point the nose at the 
ground and try diving at between 350-400 mph - this is useful in later levels 
when one fire extinguisher per engine isn't enough.