Pirate airship boss

[Castron]

How are you supposed to take care of the big pirate blimp?
The game points me towards a vent as a weak spot but when I stuff it with a balloon it starts leaking oil and nothing else happens. No other vents, no damage.

[rich.h]

On the frontside of the Blimp is a passage to fly through the whole thing. There you find the weak spots.

[[IDFK] Dutch]

There's one vent on the bottom, one on the left rear, and one on the front right. After you block all three vents, doors will open on the front and rear of the blimp and you can fly through it and destroy its weakpoints.

[Legata Flavia]

You have to block the bottom vent with nearby balloon and then fly inside and shoot everything.