Cowan was 60 years old and was reputed to be remarkably astute. A story told to illustrate this was that once, for some reason, he was unable to collect a sample of air himself and asked a fireman to get it for him. The man did so, but somehow punctured the balloon on his way out of the air-lock. Rather than admit it, or go back for another sample, he blew into another balloon which he handed to Cowan. Soon after he had begun to analyse it, Cowan sent for the fireman and said, ‘You’d better get something for your breath. It’s foul’. Nothing, it was said, ever slipped his attention. He never minded going down to 50 pounds pressure to obtain his samples, and there was no case on record of foul air in a compartment which he did not discover in good time.
When a man works under pressure, air in his lungs, nose, mouth and ears is increased as the pressure rises. The air pressure must therefore be equalised on the ear-drums, and if the Eustachian tubes become blocked there is likely to be considerable pain, with bleeding at the nose and ears, and the ear-drums may suffer permanent damage. At high pressure the body tissues are rapidly saturated with nitrogen. After long exposure to high pressure, gradual decompression is essential if harmful effects are to be avoided, and the worker must be restored to normal atmospheric pressure without the liberation of nitrogen in dangerous quantities in his bloodstream and tissues. Decompression tables have been calculated giving the approximate periods for a man to stay in a decompression chamber so that nitrogen will safely leave his blood without expanding into bubbles so large that they cannot pass through the capillaries. The period of decompression varies with the length of time a worker has been in a condition of compression.
When a fresh compartment was opened Cowan was the first man to enter. It was his theory that the poisonous gas was thrown off by rotting tarpaulins. Once, when a man was reluctant to go down because of the risk of poison-gas, Cowan offered to prove that there was no danger of combustion by sitting inside the compartment and smoking a cigar.
Figure 4. Bayern – sectional elevation, bow afloat and 29½˚ list.
On 18 July a main drainage pipe burst, allowing compressed air to rush into the forward part while the compressors were still busy. The wreck broke free and the bow rose prematurely 10 feet above water. The terrific expansion of air consequent upon this brought up the stern, and the ship rolled awhile as escaping air threw up great fountains of water. She narrowly missed surfacing upon the salvage ship, Bertha, which was moored close by. Then she lost buoyancy again and slowly sank. Divers discovered that when the ship had risen she had shed four gunturrets weighing 2,500 tons. This had changed the centre of gravity, and much extra work had to be undertaken before another attempt at refloating could be made. For example, it was decided to crush the forward conning tower up into the ship. The conning tower was in two parts, comprising the heavily-armoured conning tower itself and a square armoured communication trunk inside the ship which extended through four decks. When the latter had been crushed far enough up into the ship, toggle bars were inserted into holes cut into it so as to hold the conning tower in the crushed position.
During this month, tragedy struck when John (‘Busy’) Bee of Portsmouth died on Bertha shortly after rising to the surface, having left the decompression chamber too soon. He was not a young man and the strain had been too much for his heart.
It had been intended to make the next attempt at lifting Bayern the following day, but weather conditions were unfavourable. Moreover, for no apparent reason Bayern had developed a list to port of about 42 degrees, and it seemed that she might roll right over on her side. When she had reached the bottom three air-locks were completely under water and out of action. Extensions were fitted to them, the list was reduced to three degrees, and for several days stability tests were made.
On 1 September, after eight months’ work, it was decided to try lifting her again, and all compressors were put on full power. Every man was at his post when the ‘stand by’ order was given. five minutes later, ‘cut pipe lashings’ was ordered. Another two minutes and she shuddered and began to rise. The after air-locks had moved slightly as the stern freed itself. Every two feet of lift lowered the sea water pressure by one pound per square inch. The expanding air inside reached explosive force and Bayern shot to the surface within 30 seconds, the released surplus air projecting huge columns of air and water 150 feet into the air. So rapid was the rate of lift that even when the ship was ten feet above the surface, water six feet deep was still cascading off the bottom, the salvage steamers rolling heavily in the turbulence. Two million cubic feet of surplus air had to be expelled if the ship was not to burst with 50 pounds pressure per square inch at the bottom of the hulk and ten pounds at the top. Columns of water shot up as the air rushed out, and in 40 seconds or so the men on the air-locks were from 40 to 70 feet aloft swinging about until the ship levelled off.
The biggest ship ever raised from that depth of water was now ready for the breakers.
McKenzie considered this to be the finest piece of salvage the firm had undertaken, hampered as they had been by a bad summer, high winds and appalling weather.
On 2 September, 24 hours after being raised, Bayern was towed four miles and beached in shallow water about one mile from the base at Lyness. A few days later she was towed on a spring tide to Lyness where she was prepared for her 260-mile tow to the breakers’ yard at Rosyth.
The next two ships to be considered were König Albert and Kaiserin. Both lay in deeper water, and König Albert was chosen as the first of the two. Her keel had been laid at the Schichau Yard, Danzig, in July 1910 and she had been completed in 1913. The König class of ships were the first German battleships with all turrets on the centre line. Their greater beam gave them good underwater protection, far better than any British battleships enjoyed. König Albert had missed the battle of Jutland, being in dock for a re-fit at the time.
In October 1934 four of the firm’s best divers made a thorough survey of the wreck. They found her bow in 23 fathoms and her stern in 21 fathoms. She had a port list of about nine degrees, and was upside down with all her turrets and superstructure completely buried in soft mud. It was realised that salvage would be extremely difficult and that the only method of raising her was again by the use of compressed air. However, the salvage team now had plenty of experience, and their first task was to locate and seal with a rapid hardening cement all bottom valves, main inlets, submerged torpedo tubes etc. The ship was divided into six sections, and air-locks were made ashore in sections and towed out as was customary. As the lowest depth over the wreck’s bottom was 85 feet, the air-locks had to be 100 feet long. These were the longest air-locks so far made, and the placing of these 25-ton cylinders in choppy seas as they swung from a 70-foot jib on the pontoon was correspondingly difficult. Fairly calm days had to be chosen for the work, in winter, at Scapa Flow, such days were rare. The first air-lock was fixed on 29 November. By the end of April 1935 eight air-locks were in position, and work inside the ship was being undertaken by some 40 men working in relays at pressures ranging from 45 to 55 pounds per square inch.
There were months of difficult and dangerous work spent in repairing the damage inflicted by the German officers and crew before the vessel was scuttled, and the far greater damage caused by the tremendous rush of water against bulkheads as she turned over. Again doors had to be strongbacked, heavy pipes broken and blanked, hundreds of cables, ventilators etc cut, and all apertures sealed before bulkheads could be made watertight. Frequent delays resulted from gales and other adverse weather conditions when transit between the air-locks and the salvage steamers was difficult and often dangerous. Sometimes workers on airlocks were surprised by sudden storms and were marooned for hours before the salvage steamers could take them off. There were also frequent illnesses from working in compressed air, though immediate treatment was always available on the salvage steamers and ashore.
By the third week of July 1935 all bulkheads were sealed and final preparations for the lift began. It was decided to
make no effort to correct the list of nine degrees before the actual lift took place; the best and safest method would be to raise the fore end first, then correct the list if necessary, and finally lift the stern. On 27 July the forward sections were almost at lifting pressures when a south-easterly gale temporarily halted preparations. The new salvage steamer, Metinda, had to slip her moorings and anchor off to prevent damage. Bertha, however, was able to hold on and maintain air pressure in the wreck.
It was 48 hours before the gale blew itself out and Metinda could regain her position and resume pumping. On the following day König Albert’s bow began to tear free. It was calculated that some 3,500 to 4,000 tons extra buoyancy were needed to break the suction and to drag turrets, superstructure, etc, out of the mud. The surfacing dwarfed even the spectacular eruption of previous ships. For the first two or three feet the bow rose very slowly, then the terrific expansion of air carried the ship to the surface. The bow soared higher and higher until in half a minute it was 20 feet clear of the water, and tremendous spouts of air, water, oil and spray completely obscured the forward air-locks as a million cubic feet of surplus air escaped.
The port list increased slightly as the bow rose, but expanding air in the port bunker reduced the list to seven degrees, at which it settled. Everything now depended upon the quick and efficient execution of orders. No hitch occurred and in a few seconds 22 lines of flexible pipe and six anchor wires were smartly slackened or tightened on words of command. Compressors were connected two hours after the bow had lifted and in three sections pressure was raised almost to lifting pressure. Work continued until 22.00 hrs when operations were suspended until early next morning. Then compressors with a capacity of over 3,000 cubic feet of air per minute were connected aft. Just before 10.00 hrs the ‘stand by!’ signal was given. A few minutes later the stern freed itself and rushed to the surface; the salvage vessels rolled and sheered in the turbulence, but all wires held and the list disappeared. By noon there was a freeboard fore and aft of 14 feet, and the 100-foot air-locks stood like the chimneys of brickworks against the skyline.
On the following day she was towed two miles to shallower water and beached, her funnels, bridge and superstructure touching the bottom. Later these projections were blasted away, and the ship was towed to her doom at Rosyth.
One of the many tasks of R.R. Drysdale, manager at Charleston and Rosyth of the yards of Shipbreaking Industries Ltd, a subsidiary undertaking of Metal Industries, was the preparation of estimates of the sales value of scrap obtainable from each ship. The weight of the ship was calculated from the dimensions given in Jane’s Fighting Ships. The weight of scrap was based on expected arisings from the original complete ship as no records were available to show if any tonnage was missing at the time of purchase. The estimated weight of Bayern, for example, less various allowances for water in boilers and a safety margin of ten per cent for losses from unforeseen factors and causes, was 23,520 tons. The actual out-turn based on the distribution of the ship’s weight amounted to 22,012 tons. When the ship was broken up, the metal obtained totalled 20,835 tons. Its sales value was estimated to be £118,463 and, in fact, after a deduction for the cost of carriage, £112,784 was received, of which some £50,000 was profit.
Figure 5. König Albert.
Above: section of wreck showing list.
Right: typical air-lock.
Below: the subdivision of the ship.
Bottom: the ship in the bow-raised position.
Hindenburg, bought by Metal Industries Ltd from Cox & Danks, yielded 21,557 tons of metal, the greatest quantity. The smallest quantity, 16,172 tons, was obtained from Moltke. From five ships, Bayern, König Albert, Kaiserin, Friedrich der Grosse and Grosser Kurfürst, 99,439 tons of metal were obtained, consisting of 95,598 tons of ferrous metal and 3,841 tons of non-ferrous metal. This realised £629,670, a figure which represented a difference of only 3.9 per cent on Drysdale’s estimates. It was this kind of meticulous attention to detail in all McCrone’s overall administration of the operations which enabled Metal Industries to make a good profit where Cox & Danks had failed. For the curious, the residual remains of Friedrich der Grosse as shown by Drysdale’s working papers are given in Appendix 3. The degree of accuracy in estimating the sales value is remarkable.
During this time armour from the salvaged ships was being bought by world markets. Considerable quantities were sold to Essen for Germany’s new fleet, ironically at a time when England’s own naval reconstruction was handicapped by the lack of top-grade armour plate similar to that being exported to Germany. Then Hitler’s government began to make enquiries about the big guns, claiming that they were needed for coastal defence. As it was suspected, however, that the guns were wanted for second line vessels such as monitors, the British Admiralty was consulted about export licences. One morning a signal arrived from the Admiralty that the big guns were not to be exported, upon which the works manager rushed over to the dry dock and ordered the foreman to mutilate immediately the gun barrels and breech blocks of all big guns, and just in case the Admiralty extended its veto, to mutilate the secondary armament also.
Various methods were adopted for breaking up the metal, one at least, such as the ‘dropping ball’, having been in use for three-quarters of a century. This was used mainly on cast iron. A heavy ball on a wire jib was hauled to the maximum height by steam power. At the top it depressed a trigger which declutched a winch barrel and allowed the ball to crash down on the metal placed beneath it. Big electric motors were used to cut plates of hard steel up to two inches in thickness, and plates up to eight feet in length and one inch thick were within the power of large shears. Steel plates were detached from the hull entire and swung into the yard to be cut into convenient pieces. Twelve-inch plates could be cut at the rate of eight or ten feet per hour, and thin plates at 50 feet per hour. Between plating and hull of the capital ships lay teak three inches thick. Unfortunately there was then little demand for teak, but it was useful in the construction of McCrone’s greenhouses, garden furniture and the doors of his house where it looks substantial enough to outlast time itself.
Soon after König Albert was docked Metal Industries received a signal from the Secretary to the Admiral of the Dockyard that her arrival had coincided with a large increase in the number of rats in HMS Caledonia, the boy artificers’ training ship, and it requested that appropriate action be taken to destroy them. Metal Industries’ manager promptly telephoned the secretary to enquire if his signal was to be taken seriously. ‘It certainly is,’ was the reply. ‘Then’, said the manager, ‘our rats are easily recognisable. After fifteen years under the sea, they all have webbed feet and many have German SMS König Albert cap ribbons round their necks.’ The matter was promptly settled by the touch of humour. ‘For heaven’s sake, cancel the signal and shove it in the WPB.’
12
The Last of the Big Ones
THE NEXT SHIP to be tackled, Kaiserin, was a battleship which had been completed and commissioned in 1913. Her precise location was not known, but she was found within an hour by sweeping. She lay in 23 fathoms about three-quarters of a mile from the island of Cava, and three and a half miles from Metal Industries’ base at Lyness. Divers fixed mark buoys forward and aft. Bertha was moored in position over her, and the company’s best divers carried out a survey. They reported that the ship lay bottom up with a starboard list of 11 degrees. The water at her fore end was 23½ fathoms and aft 21 fathoms. Her superstructure and funnels were crushed badly as was expected, but the hull was sound. She belonged to the same class as König Albert and therefore all details of her construction were known.
The same method of lift as before was adopted, and air-locks were of approximately the same length also; the time for fixing an air-lock varied from one to several hours, weather being the main difficulty, as a 25-ton air-lock swinging from a 100-foot jib became a lethal weapon in the slightest movement caused by sea or swell. More than once, when sudden gales sprang up, the salvage
team had to shelter on the pontoon before an air-lock could be secured. The first was fixed in July 1935 and the others at intervals of about two weeks. All were in place and secure before the end of October.
Yet again a highly dangerous mixture of combustible gases in the ship ruled out the use of oxy-acetylene or oxy-hydrogen cutters, apart from the fact that there was only 1.1 per cent of oxygen present. Constant analyses were made by Cowan. However, each section was exhausted to atmospheric pressure and recharged several times with fresh air, and the men could then work without undue discomfort.
Shifts could work for only short periods which varied daily from one and a half to three and a half hours followed by long hours of decompression under cramped conditions in the airlocks. To add to the usual difficulties of making bulkheads airtight and working in mud, oil and slime, bulkheads had been badly distorted by the rush of water when the ship had sunk and turned over while doing so 17 years before.
From Jutland to Junkyard: The raising of the scuttled German High Seas Fleet from Scapa Flow - the greatest salvage operation of all time Page 13
