Now US Airforce has AC-130U "Spooky" Gunship

Armanent :

• 1× 25 mm (0.984 in) gatling gun
• 1× 40 mm L60 Bofors cannon
• 1× 105 mm M102 howitzer

EDIT
You can see it in action in movie "Transformers"
Or even try to be in one in CoD4 (one of the missions )

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Handle every stressful situation like a dog.
If you can't eat it or hump it.
Piss on it and walk away