Nothing stupid about the question.

If you haven't come across the word, how will you know what it is?
It's a Motor Torpedo Boat. 96ft long and capable of speeds of 60 knots+

Designed and manufactured by Vosper Thorneycroft in the 50's/60's
Perkasa is the name given to it when it was bought and used by the Malaysain navy.
Checkout my avatar.

John