Lighter-than-air craft can linger over an area for long periods with very low fuel expenditure, can reach higher altitudes than are possible with heavier-than-a

Lighter-than-air craft can linger over an area for long periods with very low fuel expenditure, can reach higher altitudes than are possible with heavier-than-air craft, and could in theory carry much heavier cargo. They are also quite hard to shoot down with guns, but that might not hold true with surface-to-air missiles.