The raised bow is a visual cue that distinguishes the original Vosper form from later boats built in quantity. As the bow rises, the torpedo launchers appear lower in the profile. The change improved seakeeping rather than simply altering the boat's appearance. It also brought a modest speed benefit, showing how operational experience could refine a fast craft's hull without changing its basic mission.
Notable Point · 39:32-39:58
A raised Vosper bow improved seakeeping
Later Vosper boats raised the bow around the torpedo launchers, improving their behavior in rough water and slightly increasing speed.