"This Man's Navy", made over sixty years ago, depicts real Navy blimps in action. No CG here!
Wartime blimps were made by Goodyear, and the larger ships (K Class and M Class) carried depth charges, and .50 caliber machine guns. While a few blimps were shot down doing escort duty, they more than made up for it in their effectiveness in their role in anti-submarine-warfare. It has been said that no convoy escorted by a naval blimp lost a ship to enemy action. Much as a visible burglar alarm encourages those that would thieve to move on to easier targets, a convoy with a blimp overhead was too risky a target for an enemy submarine -- not so much because the blimp was armed, but because the blimp could call in the enemy location to a destroyer that would finish the job.
Enjoy this "best of" video produced by IncredibleWorldViews
And if you'd like the whole thing, you can find it over at Scooter Movies Shop on DVD.