Traditional periscope replaced on submarine HMS Astute


Unlike most submarines HMS Astute does not have a traditional periscope, but uses a mast fitted with cameras that can record and analyse what is on the surface.

Lieutenant Commander Louis Bull explains how it works.

Copyright © 2015 BBC. The BBC is not responsible for the content of external sites. Read more.

This page is best viewed in an up-to-date web browser with style sheets (CSS) enabled. While you will be able to view the content of this page in your current browser, you will not be able to get the full visual experience. Please consider upgrading your browser software or enabling style sheets (CSS) if you are able to do so.