On the morning of June 2nd 1967 the 13,000ton German tanker Essberger Chemist was sailing a westerly course 90 miles south of the Azores carrying a quantity of pure alcohol and acetol; a material used in the construction of valves, bearings, gears and any component that requires a high resistance to friction. The night before had produced some unsettled weather but this had subsided with dawn and so the members of her 46 crew not on watch were assigned to repaint the rear-most tank deck which had started to look worn out. Each of the men assigned this tedious duty no doubt looked forward to 1000hrs for this was the usual time that the crew were allowed a brief break to have a hot drink, a quick bite to eat in the galley and have a smoke.
The minutes ticked down and at 1000hrs exactly the men laid down their paintbrushes and went aft towards the galley. They had barely sat down at their tables when the deck below their feet trembled and the ship roared with a loud dull booming sound. It was quickly followed by a second one which sent the resting crewmembers rushing out on deck to investigate. What they saw must have horrified them. The forwardmost superstructure housing the bridge was concealed by bellows of smoke comprising of thick, poisonous fumes that even in the open air with a breeze across the deck made breathing difficult. Where they had been standing only minutes earlier painting the tank deck there was now only smoke, flame and charred metal.
But the terrified sailors had an even greater surprise awaiting them.
Acting on their training the men closed the watertight hatches and assumed their damage control stations unsure as to whether any of the crew forward of the blast had survived. It came as some relief when they noticed that the smoke and flames were already dying out thanks to the way the ship was designed that limited the spread of fire within the ship’s dangerous cargo. As more and more of the smoke cleared they began to fathom just how powerful the explosions had been as the damage to the ship became more evident until finally they realised that their ship had literally been cut in to two pieces almost perfectly down the middle.
In the forward half of the ship where the bridge was located efforts were already underway to get help. The radio operator was instructed to transmit a brief SOS explaining that there had been an explosion onboard before switching on an automatic homing beacon that the Portuguese Coast Guard could home in on. Realising his ship, if a singular description was even accurate at that point, was lost and fearing either sinking or additional explosions the captain ordered that the seaboats be launched and that the crew abandon ship. At 1055hrs the last of the 46 man crew got off the vessel. Incredibly, none of them had been seriously injured. The crew put some distance between themselves and the two sections of the ship that now stubbornly refused to sink; the many sealed off sections of the ship such as in the cargo hold provided sufficient buoyancy to keep the two sections on the surface.
It was three hours before the first Coast Guard aircraft sighted them. The aircraft circled around and dropped lifeboats, radios and rations to the unfortunate German sailors. Two tugboats then arrived on the scene at 1900hrs and took aboard six of those that needed medical attention while the others spent most of the journey home being towed back in their life rafts. They were shaken up by the mysterious explosion but they were very much alive.
Over the next few days aircraft tracked the two floating pieces of ship as they bobbed about in the mid-Atlantic. Reconnaissance photos showed that the aft portion of the ship had lost most of its toxic cargo in the blast and was intact enough to risk a salvage operation. Tugs from the Azores set out and put lines on it before towing it in to Ponta Delgada it arriving there on June 5th. The operators of the ship wanted to then tow in the foremost part of the ship but the authorities in the Azores refused to grant permission for it to be put in to Ponta Delgada as well. They were concerned about the estimated 1,700tons of chemicals that were still aboard in the cargo hold and had doubts about the soundness of the wreck under tow. As the shipowners and the authorities in the Azores argued over permission to bring the forward section in, reconnaissance flights showed that it was now floating northwards towards the Azores thus endangering shipping and eventually the local population if the ship ran aground and spilled its cargo. As a precautionary measure a salvage tug was sent out and shadowed the fore section to help guide it away from oncoming ships if necessary. As the days dragged on and with the authorities in the Azores still refusing to allow them to tow it in to Ponta Delgada the owners began to look at alternative options.
On June 19th, more than two and a half weeks after the blast, the Royal Navy nuclear attack submarine HMS Dreadnought put in at Gibraltar to begin a 10-day maintenance period at a commercial drydock on the island. The Royal Navy also took the time to evaluate how well the vessel’s sonar had performed on the journey from its base at Rosyth in Scotland and this involved taking the system apart so it could be analysed by Royal Navy engineers. This gave the ideal excuse for the bulk of the submarine’s crew to take shore leave. One of those remaining aboard however was one Lieutenant J. Higgins who on the 21st of June, as officer of the watch, received a call from the Admiralty enquiring how long it would take for the submarine to be returned to operational status to which he replied twenty four hours. Lieutenant Higgins was instructed to make ready to sail and the orders went out to recall the ship’s company including the ship’s captain, Commander Peter Cobb, who was holidaying in Tangiers.
In fact it took just twelve hours to get the submarine ready for sailing but being a nuclear powered vessel operating in a commercial harbour Dreadnought had to be towed out before starting the nuclear powerplant. It was with some amusement that the crew received orders that they were to assist with the Essberger Chemist incident by possibly providing the means with which to finally sink the remaining half of the ship. It was believed that torpedoes could sink the carcass of the ship that was left thus removing the threat to shipping while the resulting explosion would destroy the remaining chemicals onboard in order to limit the environmental impact. With no progress being made to secure the salvage of the remaining forward half of the vessel the owners approached the British government to request assistance in sinking her no doubt fearing the repercussions if the forward half of the ship damaged or even sunk a passing vessel as it floated in to maritime traffic. There must have been more than one sailor who joked that the Royal Navy Submarine Corps was asked to do the job because they’d had a lot of experience sinking German ships in the past!
As Dreadnought made ready for sailing another Royal Navy asset, HMS Salisbury, put in to Ponta Delgada for refuelling following a tour in the West Indies. HMS Salisbury was a Type-61 frigate whose primary function was to provide long range radar picket and fighter control duties for a carrier task force and was armed primarily with the standard dual 4.5inch naval guns for self-protection. It was decided that Salisbury should be put to sea as well to support Dreadnought mainly by being the eyes of the operation.
This was not the first time that the Royal Navy had to help nullify a threat to shipping and wildlife from a wrecked tanker. As a matter of fact it was not the first time that year! On March 18th 1967 the Torrey Canyon tanker struck a reef off Cornwall spilling thousands of tons of oil in to the sea. The Royal Navy’s Fleet Air Arm and the Royal Air Force launched air strikes on the wreck with the hope of breaking up the ship and setting the oil slick on fire so as to burn it off and prevent the oil from contaminating the coastline. Unfortunately it was met with limited success and primarily served to create large clouds of choking black smoke although it did sink the wreck and prevent it from breaking up which could have resulted in a similar situation to the Essberger Chemist.
When the Royal Navy vessels arrived on station they observed that the forward section had developed a list to starboard from taking on water but still showed no signs of sinking and was now floating at a speed of around 1 knot. On the morning of June 24th all sides agreed that the only option left open was to sink it and so the orders were sent out to HMS Dreadnought. With live weapons being discharged there was an intensive operation to clear the surrounding area of shipping. Two RAF Avro Shackleton MR.3 maritime reconnaissance aircraft were deployed from the UK to begin scouring the surrounding areas and warning away any vessels that might stray in to the area. Once the RAF and radar operators aboard Salisbury were satisfied that the region was clear Dreadnought’s captain gave the order to dive the submarine. He then took his vessel out to a range of one mile from his target as the torpedo teams prepared four 21inch torpedoes. Once in position the captain took one final look around with the periscope before settling on the target. Satisfied that his vessel was in the optimum firing position he gave the order to unleash the torpedoes.
One after the other the four torpedoes were spat out of the Dreadnought’s forward tubes and went racing along towards their target at a speed of nearly 46knots. After a short time the first torpedo struck resulting in the distinctly audible “thud” sound inside the submarine that such weapons produced. It was quickly followed by a second and then a third but no fourth. The torpedoes had struck along the hull in a line but the fourth torpedo missed passing very close to the target before carrying on until it burned out its fuel. The detonations produced massive towers of water that spat out metal fragments and seemed to engulf the target while flames from the igniting chemicals produced an arching spire of black smoke as they burned.
Despite one torpedo missing the target the operation was deemed a success and Dreadnought surfaced a short time later where the lookouts in the coning tower had a grandstand seat watching the burning forward section of the ship start sinking. The Shackletons continued circling overhead trying to assess the damage which was made difficult by the plumes of smoke. The now charred wreckage had indeed began to sink but then frustratingly stopped just as it was about to slip below the surface. In one final defiant act the wreck stayed afloat and thus the danger it represented remained thanks to the many watertight doors that had been closed by the crew in the wake of the initial explosions which maintained her buoyancy – surely a credit to the ship’s designers.
Discussions between Dreadnought and Salisbury reasoned that it would be overkill to fire another torpedo at it and so the decision was taken for Salisbury to start firing her 4.5inch dual-purpose (DP) guns at it. Dreadnought moved clear of the wreck as Salisbury started her barrage. After several volleys of shells the bulkheads finally collapsed rendering the watertight doors ineffective and the remains of the Essberger Chemist slipped below the ocean bringing an end to the whole affair.