The Eagle is a heavy hunter aircraft, able to equip incredibly strong armor as well as decent weapons. Furthermore all its weapons excluding one or two are versatile. This allows it to do anything anywhere, and makes it the ideal hunter. The weapons are strong at the higher levels, but don't be expecting to kill any sets of Behemoths.
Though the Eagle is slow, they get a special: Megathrusters.
Also due to its high health, it's known to be effective at clearing away airmines by just plowing into them and taking the bits of damage.
It should be noted that most would agree that Eagles are most effective with their TL120 weapon.