HMS Belfast's primary armament throughout her life was her 6-inch guns. It took over 200 men working together over 8 decks to keep these guns firing - what made these guns so complicated? Our experts take us from the Gun Direction Platform to the Fire Control Table, then into A-Turret and A-Turret's shell room to see how exactly they worked. We then take a look at her secondary 4-inch guns and where her two Supermarine Walruses used to stand.

Exploring the 6-inch and 4-inch guns

Andy Curran (AC): Hello and welcome to HMS Belfast. My name's Andy, and I'm the conservation manager for the ship. I've worked here about 20 years now in various roles. At the moment, we're standing on the fo’csle of the ship. Behind me is A Turret and up to my left, B Turret, the two forward, six-inch turrets. HMS Belfast was built by Harland & Wolff. She was first laid down in 1936 and launched in 1938. During her time in the Navy, she went through a major rebuild, a major modernization and several refits, culminating in 1959 until the end of her life or naval life in 1964.

So now we're going to go up to the Gun Direction platform and look at the director for the primary armament, the six-inch guns.

Fred Sutton (FS): We have just come up from the fo’csle, so we're now on the gun direction platform or GDP, as it was known. My name is Fred Sutton. I'm a volunteer on board HMS Belfast doing conservation. I also joined the Navy when I was 15 and became an Ordnance Artificer on board various ships. The only original bit of kit on board the Gun Direction platform from the first build is the director behind me, which is up there.

This was installed during the manufacture, but she had an optical sight on there, which was a 20 foot optical platform with a binocular in each end. During the refit after the mining of Belfast in Devonport, that was taken off and the radar was put on there. One of the first ships in the Navy to get a radar.

Up in the director, you would have about nine people up there. Their job was to find the enemy, hold it. And that would become the line of sight for the guns.

Film narration: “To make it easier, we keep the angle at one end at 90 degrees, and only at the other end do the squinting. Watch the T approach and the line converging.”

The gunnery officer would also observe the enemy ship and try to decide how fast it was going from its bow wave. He would also try and estimate the inclination from how it is bearing to us. That information would be sent down to the transmitting station where the system worked out what angle they needed to go for the guns.

The way the Navy used to do it was they would take the range and take off 200 yards and fire the first shot. They would then immediately fire the second shot, but they would put the range up 400 yards and then they would come back 200 yards to fire the third shot. And so the third shot should land on the ship. Once you see a straddle, then the commanding officer would say, fire for effect. So you just keep firing then. So it was an iterative process, but I think really quite efficient.

We've now moved down from the gun direction platform, which is on 04 deck to the transmitting station, which is on four deck. This is the brains of the gunnery system.

We've got the Admiralty Fire Control table here, which is the original one which was installed as the ship was being built in 1938. So it solves the problem of where to aim the guns, both in training and elevation. It would have been manned by the Royal Marines and as action stations closed up, they would come in here. There would be a gunnery officer there who would be in charge and they would start setting on information. You've got two dials here: own ship and enemy ships. All of the own ship information would have been put on right away. The engine room would be given speed, and that would be sent down here. Then the information would come down from the director - line of sight, the bearing, the speed estimated by the gunnery officer... But we also have to have barometric information, what the air temperature is, what the air pressure is, how old the guns are. Once you've got all the information ready, the order would go from the bridge to shoot. It would be very quiet in here. Everybody would be doing their job and the guns crew will be working like mad to keep the guns firing.

For me, this is the most amazing compartment on the whole ship. And this is the most amazing piece of kit. It's the brains of the gun. And when I started doing conservation on here, Andy Curran asked me to have a look inside it. So I took a few cover plates off and looked inside and it is basically pristine. I couldn't see any problems with it at all.

So now we've done the brains, we're now moving over to A Turret, where the punch comes from.

AC: We’re now stood in A Turret on HMS Belfast. This is the foremost Turret of the four six-inch turrets fitted to the ship. Each gun is capable of firing eight rounds per minute to a range of about 14 miles. The warheads are 112 lb and they are fired using a 30 lb cordite charge.

So in this turret there are three guns, each with a crew of seven people. There's the captain of the turret who sits at the back with his own communication number, and a layer, trainer and setter in a small compartment on the far side of the turret there. So there's 26 people in here. So drills are very important. These guys spend a lot of time training so each knows their own job, knows where to be, and are able to keep up this high rate of fire.

We’ll now have a look at how the guns actually were set and fired.

What we have here then is the elevated position for this right hand gun. The transmitting station would have set the angle that's required and - the gunner here literally just lines up the gun so that the arrows are lined up and that gun is in position, ready to fire.

Each gun has its own hoist for shells and hoist for cordite. So during the loading, the bridge is open. The shells come sliding down these chutes here into the loading tray, ready for loading the gun. Two loaders push the shell right up into the gun and that's followed by cordite, 30 lbs of it. It comes up via a cordite hoist in these Clarkson tubes, and each charge looks like this. And that is pushed up behind the shell in the gun itself. Following that, the bridge is closed, and the vent tube is fitted into the small breach here, and that fires a flame up through the breach and sets off the cordite in the breach itself.


John Harrison (JH): “When I went on board HMS Belfast - a brand new ship - I didn't know what to expect. I’d only come from a small cruiser and there was this beautiful big cruiser, brand new, that I was informed that I was put in charge of A and B Turrets. It's your responsibility is to maintain those guns to fighting efficiency, should they be required. So you do a shoot. The noise down below there for a first experience was quite surprising. You couldn't feel any shock. No compression. It was just a dull thump, rumble, shudder and your feet went - you didn't know whether that was the turret revolving or whether the ship was heaving or whatever…”


AC: Now we've come down to A Turret shell room. This is home for 600 shells. That's 200 per gun. And they were stored in the bunkers around us with a ready supply sat on this carousel. The carousel had an independent motor so it could slowly rotate to make sure that the guys loading the shell hoist had a shell to hand.

Where I'm stood here rotated with the turret and pointed in the same direction. The crew of nine down here would have been responsible for breaking the shells out of the bulk storages, fitting the fuzes and sending the shells up to the turrets via the shell hoist. These are the shell hoists themselves. They're driven by hydraulic motors from a power plant just below the turret. The shells are slotted into them and taken straight up to the turret themselves. Below here is the powder magazine, which has a similar set up and three more hoists,  which are seen over the back here. And they take the powder charges straight up through those holes into the turret.

The machine we see around us here was the original of the ship and really didn't change at all over the whole life of the ship.

So we've looked at the main armament, the six-inch armament for the ship, over 200 people, all working together to keep four turrets working and 12 guns firing, all in constant communication over eight decks. So now we're going to go and look at the four-inch secondary armament.

We are now stood beside a four-inch gun mount, one of four fitted to the ship. These are quick firing mounts and they can be used for anti-aircraft and surface mode. They can fire shells through about 39,000 feet or about 12 and a half miles in surface mode. They're crewed by 15 gunners and in that semi-automatic mode could fire 20 rounds per minute per gun. Originally, there were six of these mounts fitted to the ship. In 1944 the two aft ones were removed to reduce top weight, while 20mm automatic weapons were fitted to the upper deck. You can hear noise going on in the background. Conservation is constantly going on on Belfast and at the moment we're repairing the upper decks.

On the gun mount itself, we have positions for a layer and a trainer who operated the training angle for the gun and the elevation angle for the barrels. The bulk of the crew spent their time loading. Ammunition was supplied from the four-inch magazine on 5-deck via hoists and a conveyor belt system to keep resupply to the gun mounts themselves. In the front here there's a fuser unit. These became redundant once proximity shells started to be used in the fleet, but were left on the mounts to counterweight and balance the mount itself.

These gun mounts were directed by radar controlled directors based on the deck above. The signals came down very similar to the six-inch armament where the layer and trainer would follow arrows to direct the guns.

We’re now on the boat deck of HMS Belfast. Early in the ship's life, this was in fact the flight deck. Behind me, there would have been two hangars to house the two Walrus aircraft that the ship carried. Over here, there was a catapult to launch the aircraft, and the ship carried at a time two cranes for retrieving the aircraft when they landed in the water alongside. They were primarily used for reconnaissance, but could also be armed with depth charges and bombs. After the refit, the modernization refit of 1959, this became the boat deck and all traces of the aircraft were removed except for these parts standings on which the rails ran.

Interviewer: “Obviously, Belfast's armament changed over the years. Do notice the changes now with the ship from what it was in your day?”

JH: “Yes, the turrets are still the same, but in mid-ship there is no catapult; there are only two anti-aircraft guns, whereas before there were six, three aside. The fuze trains have gone, which were midship, and also they’ve got antenna, up there for detection work, which we didn' t have at all - there was no such thing as radar in those days. If you could see you hit it, if you couldn't see it, it wasn't there. Those are all the modern equipments on the Belfast, which in some ways I wish we’d had. But the way it goes.”

Interviewer: “And I was also going to ask you about the paint scheme that's on the ship. Was it different again?”

JH: “Oh, yes, just grey, it was just grey. There are no camouflaging on the Belfast at first. Remember we left Portsmouth for a shakedown cruise. And finished up being mined. We never went back. And then again that’s the luck of the ship. Still afloat. Welding. I’m a great believer in welding.”

AC: HMS Belfast had its final refit in 1959, when she was modernized before rejoining the Far East Fleet. She was paid off into reserve in 1964 and became a museum here on the Thames in 1971. And this is what you can see here today.


Related content

HMS Belfast and Scharnhorst thumbnail
Second World War

Battle of North Cape: HMS Belfast and the sinking of the Scharnhorst

Scharnhorst was one of the most dangerous German warships of the Second World War, and the last of her kind. In late December 1943, she was sunk, after attempting to intercept two Arctic convoys. What happened at the Battle of North Cape?

HMS Belfast in Korea thumbnail
Cold War

Korean War and HMS Belfast: The hottest point of the Cold War?

The Korean War broke out on the 25th June 1950 when communist North Korea invaded South Korea. HMS Belfast was soon in action. In her two years of service in Korea, she saw more action than at any point during the Second World War. The Korean War was primarily fought on land, so why did HMS Belfast see such intense action during this period?

Andy in the boiler room
HMS Belfast

In the Engine and Boiler Rooms of HMS Belfast

In this video, Conservation Manager Andy Curran takes us through the main machinery in the engine and boiler rooms of HMS Belfast, capable of driving the ship up to about 32.5 knots full power. We also hear from some crew who describe what it was like below deck in action stations during the Battle of North Cape.