Break the Blockade

Objectives
Take Petrov's Cluster Bombs and drop them on enough pirates to kill or destroy 25 Blockade Pirates and 10 Blockade Cannons. Once you've accomplished that, return to Bombardier Petrov at Westguard Keep. Provided item:
 * Blockade Pirate slain (25)
 * Blockade Cannon destroyed (10)
 * Petrov's Cluster Bombs

Description
All of our ships are sunk! We need your help to break the pirate blockade below in the Shattered Straits!

Take these cluster bombs and hitch a ride on the zeppelin that Harrowmeiser has 'loaned' to us. He'll fly you over the decks of those pirate bastards, and you make sure to give it to them good!

If you can't bomb them to smithereens, I'm afraid we'll never be able to break the blockade.

Rewards
You will receive:

Progress
We're talking again are we? That must mean that you've done it! You've shown those rotten Northsea pirates a thing or two!

Right?

Completion
That's what I wanted to hear! You've got the stuff,, that's for sure!

You think maybe you could come back again tomorrow when we've made more cluster bombs?

I'd have you back out there right now, but my assistant, Feknut, isn't back from collecting more bat guano for them.

I wonder what's taking him so long?