Frigate F78 HMS Kent 4.5 inch Mark 8 Naval Gun, Dover Castle Sunrise, Kent, UK

Selected for Google Maps and Google Earth

Royal Navy HMS Kent berthed at Dover Harbour's Prince of Wales Pier, 22 September 2012, to commemorate World War II 1942 Channel Dash of German Scharnhorst, Gneisenau, Prinz Eugen (Operation Fuller, Cerebus). Skyline: Norman Dover Castle, Roman Pharos (lighthouse), Saxon St Mary-in-Castro church.

Show more
Show less
Save Cancel Want to use bold, italic, links?

Comments (5)

John Latter on September 24, 2012

The 4.5 inch Mark 8 is a British naval gun system which currently equips the Royal Navy's destroyers and frigates, and some British destroyers and frigates sold to other countries.


The 4.5 inch gun has been the standard medium-gun calibre of the Royal Navy for use against surface, aircraft and shore targets since 1938. The current 55-calibre Mark 8 gun replaced the Second World War era 45-calibre QF 4.5 inch Mk I - Mk V naval guns. Like all British 4.5 inch naval guns, it actually has a calibre of 4.45 inches (113 mm).


A completely new type of 4.5 inch gun with a longer 55-calibre barrel, it was designed in the 1960s for the Royal Navy's new classes of frigates and destroyers. The new weapon, built by Vickers, was developed by the Royal Armament Research and Development Establishment using the Ordnance, QF 105 mm L13 of the Abbot self-propelled gun as a starting point (it used electrical primers). The outer shell of the gunhouse is built from glass-reinforced plastic (GRP).

The new weapon emphasised reliability over a high rate of fire, allowing a switch to a lighter, single barrel mounting and ammunition of a one-piece design.

The gun system has a combination of electrical and hydraulic components and the full system penetrates up to three deck levels below the weather deck; deep magazine, gun control room and power room, gunbay and the gunhouse.

The weapon is semi-automatic and can be operated by a smaller crew than its predecessors. With no personnel in the gunhouse, loading is supported by personnel in the gunbay to load the feed ring and in the deep-magazine to pass ammunition to the gunbay. The Captain of the Gun in the control room ensures continued weapon readiness and the gun controller in the Operations Room operates the aiming and firing process. The weapon has a rate of fire of about 25 rounds per minute and a range of 12 nm (22 km; 27.5 km with the newer High Explosive Extended Range round).

The first recipient of the new gun and mount, the Mark 8, was the Iranian frigate Zaal in 1971. The gun entered Royal Navy service in 1973 on the new destroyer Bristol.

These guns proved to be less reliable than the older 4.5 inch Mark V gun (redesignated Mark 6 gun mounting) during the Falklands War, being forced to cease fire on several occasions due to faults.

The first major modification to the mounting, the Mod 1, was developed in the late 1990s; replacing the gunhouse with a reduced radar cross section assembly and replacing the hydraulic loading mechanism with an all electric system. This particular gun has been nicknamed the "Kryten gun" by members of Royal Navy, after the odd shaped head of a robot from the British Sci-fi comedy series Red Dwarf.

John Latter

Dover Blog: The Psychology of a Small Town

This is the Images of Dover website: click on any blue "John Latter" link to access the Entry Page.

John Latter on September 25, 2012

HMS Kent

HMS Kent is a Type 23 Duke class frigate of the British Royal Navy, and the twelfth ship to bear the name.

Kent's lineage boasts sixteen Battle Honours from the three given to the first Kent of 46 guns built in 1653, to the five awarded to the ninth and tenth Kents of World War I and World War II.

Sponsored by Princess Alexandra, The Hon Lady Ogilvy, Kent was launched on 28 May 1998.

Built by BAE Systems Marine (formerly Marconi Marine) at Scotstoun in Scotland, she was commissioned on 8 June 2000 and was the first ship to enter Royal Navy service in the 21st Century.

Sources: HMS Kent and 4.5 inch Mark 8 naval gun

See HMS Kent F78 Royal Navy Frigate at Sunrise, Dover Harbour, UK (check later comments for more HMS Kent photos as they are uploaded).

Also see F235 HMS Monmouth, 70th Anniversary of Dunkirk, Admiralty Pier, Dover Harbour

More Dover Navy photos.

Ministry of Defence HMS Kent webpage.

Sign up to comment. Sign in if you already did it.

Photo details

  • Uploaded on September 24, 2012
  • © All Rights Reserved
    by John Latter
    • Camera: Canon EOS 600D
    • Taken on 2012/09/22 06:30:55
    • Exposure: 0.006s (1/160)
    • Focal Length: 55.00mm
    • F/Stop: f/8.000
    • ISO Speed: ISO100
    • Exposure Bias: 0.00 EV
    • No flash