The evening went uneventfully until around 2320 when, without any previous warning, flames were seen coming up from below, just abaft her foremast. This was followed after a short interval by a heavy explosion deep within her. The flames greatly increased in intensity and wreckage was thrown up abaft the foremast in the vicinity of P and Q wing turrets, either side of the ship abaft the bridge.
This first explosion was followed after a short interval by a second, heavier, explosion that considerably increased the volume of flame and smoke. The ship was by now totally obscured by smoke and the exact location of this second explosion could not be determined.
When the huge cloud of smoke that had obscured the battleship drifted away in the gentle evening breeze, Vanguard was gone; 845 men had been aboard her at the time of the explosion – but only one officer and two ratings survived, one of whom subsequently died of injuries received. The total death toll of 843 included Commander Ito, an observer from the Imperial Japanese Navy – then an ally of Britain. Two Australian sailors from HMAS Sydney were locked in her cells when she went up and were also killed.
The bodies of her crew that could be recovered now rest in the naval cemetery at Lyness, and a memorial stands at the end of the gravestones, overlooking Scapa Flow where their destroyed dreadnought lies in the depths.
The subsequent Court of Inquiry took place on 30 July 1917 aboard the battleship HMS Emperor of India three weeks after Vanguard blew up. The court found that the likely cause of the explosion in either P or Q magazine was either (i) the ignition of cordite due to an avoidable cause or (ii) abnormal deterioration of a cordite charge subjected to abnormal treatment during its life.
Cordite is a smokeless propellant developed in the late 19th century to replace gunpowder in large military weapons such as tank guns, artillery and naval guns. High explosive gunpowder, used since the days of sail, produced a powerful detonation in the barrel that initially accelerated the projectile – but by the time the projectile was leaving the barrel, with the force of the explosion spent, the projectile was already decelerating. Gunpowder was very destructive of the gun barrel itself and produced a large quantity of black smoke.
In 1889, a new propellant consisting of nitroglycerine, gun cotton and petroleum jelly, was developed and manufactured in thin spaghetti-like rods. It was known initially as ‘cord powder’ – a name quickly abbreviated to ‘cordite’. Cordite was not designed to be a high explosive such as gunpowder: it was developed to deflagrate – that is, to burn and produce high-temperature gases. It was the rapidly expanding gas inside the breech that accelerated the projectile up the barrel, to such an extent that the shell was still accelerating as it left the barrel, unlike gunpowder where the shell was decelerating from the moment of detonation. This expansion of cordite gas was much less destructive of the gun barrel than gunpowder.
Cordite was stored for protection in propellant magazines, deep in the ship below the waterline. The magazines for the big 12-inch guns were clustered around the barbettes and ammunition hoists.
During World War I, the British kept all their big gun cordite propellant in silk pouches stored in flashproof copper Clarkson cases in the magazines. These Clarkson cases were 5-foot-high flashproof brass or steel tubes (like large cigar cases) with a carrying handle on the side and a circular lid at one end. The top half of the cases opened longitudinally to receive and safely transport cordite in silk pouches from the magazine to the gunhouse above via the ammunition hoists. Cordite propellant charges for smaller calibre guns were housed in rectangular brass-ribbed flashproof cases with a removable lid.
The early versions of cordite required to be kept at a temperature of less than 50°F (or 10°C) by a cooling system lest it become unstable – so on all warships, the temperature of propellant magazines had to be monitored.
The Court of Inquiry on Emperor of India heard evidence that on Vanguard the temperatures of all 12-inch and 4-inch magazines were taken daily every morning by means of temperature tubes. Additionally, thermograph charts were inspected weekly by the gunnery officer.
There was however, at this time, no standardised Royal Navy procedure for taking magazine temperatures – and systems and procedures varied from ship to ship in the fleet. Some ships like Vanguard took the temperatures once a day – whilst others took the temperature three times a day.
In reaching its verdict, the court recommended that the taking of magazine temperatures should be standardised throughout the fleet. The monitoring procedure should be conducted at more frequent intervals and should be carried out under the direction of the gunnery officer by the gunner of the ship, who should physically enter the magazines two or three times a day and inspect them.
The phenomenon of ‘hot pockets’ in magazines was already known about, and it was further recommended that the readings of fixed-temperature tubes should not simply be accepted as the temperature of the whole magazine. It was noted that when cooling apparatus was in use, the difference between temperatures registered by the thermometers in different parts of the magazine became accentuated. It was suggested that the circulation of cold air in their immediate vicinity unduly affected temperature tubes in certain positions in the magazines.
Amongst a whole raft of findings and recommendations it was noted that when turned to the storage position in the magazines, the lids of the smaller calibre brass flashproof cordite cases were often found to be loose – and in some cases to have fallen off altogether.
It was further noted that in Vanguard, coal sacks were stowed in fuel spaces adjoining the P and Q turret handling rooms. These fuel spaces had no ventilation when the access hatch was closed – as was normally the case. One of the 3-inch thick bulkheads to these fuel spaces actually formed the bulkhead between it and a 4-inch cordite propellant magazine (which was being used as a 12-inch magazine at the time) and a 12-inch shell room. Here, favourable conditions for a spontaneous combustion were produced if the 3-inch thick bulkhead became heated to a dangerous degree unnoticed. The court recommended that in all ships arrangements should be made such that a considerable rise in temperature in any compartment adjoining a magazine or shell room must be discovered within two hours.
Captain R. F. Nichols, (who was in command of Royal Oak at the time she was torpedoed in the Flow in 1939), was a young midshipman on Vanguard that night. He lived to command the Royal Oak in World War II, because on the night Vanguard exploded he had been attending a concert party presented by Royal Oak sailors on the theatre ship Gourko. The show had lasted longer than intended, and he had missed his boat back to the doomed Vanguard.
Commercial salvage work was carried out on the Vanguard in the late 1950s and subsequently in the 1970s. When hard-hat salvage divers initially went to examine the wreck in the 1950s they found that the main battery turret tops had been blown off and all the 12-inch gun barrels were blown out of their trunnion mounts. One main battery 12-inch barrel, weighing 67 tons, was found standing upright some 150 feet away from the wreck, its barrel buried 15 feet down into the seabed in much the same way that the 6-inch guns from Hampshire had impaled themselves into the seabed by their barrels.
They then found A turret, complete with its barbette, standing some way away from the bow, with sections of the tripod foremast and spotting top beside it.
At the stern, the propeller shafts were bent, and one of the ship’s propellers was found lying free of the ship and was lifted. The three other propellers were subsequently blown off and lifted to the surface.
The 10-inch-thick vertical main armour belt plates were very valuable and had been blown apart. This made them easy for the salvors to lift, in comparison to the German High Seas Fleet battleships nearby where the vertical armour belts were still firmly in place. On the German battleships, salvors had to blast their way into the ship through the unarmoured sections of hull bottom and get into the coal bunkers, which were directly behind the armour belt. Here, explosive charges were placed to blow the 25-ton plates off one by one, for stropping and lifting to the surface.
The 25-foot-long 28-ton condensers were blasted out and removed from Vanguard’s turbine rooms. A number of valuable Weir pumps were also recovered. These large pumps