XVI
THE CONVOY SYSTEM
EARLY in 1917 the losses of the merchants' ships and men had assumed a proportion that called for a radical revision of the systems of naval protection. Concentrating their energies on but one specific form of sea offence, the enemy had developed their submarine arm to a high point of efficiency. Speed and power and lengthy sea-keeping qualities were attained. To all intents and purposes the U-boats had become surface destroyers with the added conveniency of being able to disappear at sight. They conducted their operations at long distance from the land and from their bases. The immense areas of the high seas offered a peculiar facility for 'cut-and-run' tactics: the system of independent sailings of the merchantmen provided them with a succession of victims, timed in a progression that allowed of solitary disposal. Notwithstanding the matured experience of submarine methods gained by masters, the rapid evolution of counter-measures by the Royal Navy, the courage and determination of all classes of seafarers, our shipping and that of our Allies and the neutral nations was being destroyed at a rate that foreshadowed disaster.
Schemes of rapid ship construction were advanced, lavish expenditure incurred, plans and occupation designed—all to ensure a replacement of tonnage at a future date. More material in point of prompt effect were the efforts of the newly formed Ministry of Shipping to conserve existing tonnage by judicious and closely controlled employment. All but sternly necessary sea-traffic was eliminated: harbour work in loading and unloading was expedited: the virtues of a single control enhanced the active agency of the merchants' ships—now devoted wholly to State service. Joined to the provisional and economic measures of the bureaux, Admiralty reorganized their methods of patrol and sea-supervision of the ships. The entry of the United States into the world war provided a considerable increase of naval strength to the Allied fleets. Convoy measures, that before had been deemed impracticable, were now possible. Destroyers and sloops could be released from fleet duties and were available as escorts. American flotillas crossed the Atlantic to protect the sea-routes: Japanese war craft assisted us in the Mediterranean.
In the adoption of the convoy system the Royal Navy was embarking on no new venture. Modern ships and weapons may have brought a novel complication to this old form of sea-guardianship, but there is little in seafaring for which the traditions of the Naval Service cannot offer text and precedent. The constant of protection by convoy has remained unaltered by the advance of armament and the evolution of strange war craft: the high spirit of self-sacrifice is unchanged. When, in October 1917, the destroyers Strongbow and Mary Rose accepted action and faced three German cruisers, their commanders—undismayed by the tremendous odds—reacted the parts of the common sea-dramas of the Napoleonic wars. The same obstinate courage and unconquerable sea-pride forbade them to desert their convoy of merchantmen and seek the safety that their speed could offer. H.M.S. Calgarian, torpedoed and sinking, had yet thought for the convoy she escorted. Her last official signal directed the ships to turn away from the danger.
BUILDING A STANDARD SHIP
The convoy system did not spring fully served and equipped from the earlier and less exacting control. Tentative measures had to be devised and approved, a large staff to be recruited and trained. The clerical work of administration was not confined to the home ports; similar adjustment and preparation had to be conducted in friendly ports abroad. As naval services were adapted to the new control, the system was extended. The comparatively simple procedure of sending destroyer escorts to meet homeward-bound convoys became involved with the timing and dispatch of a mercantile fleet sailing from a home port. The escorts were ordered out on a time-table that admitted of little derangement. Sailing from a British port with a convoy of outward-bound vessels, the destroyers accompanied that fleet to a point in the Atlantic. There the convoy was dispersed, and the destroyers swung off to rendezvous with a similar convoy of inward-bound vessels. While the outgoing merchantmen were allowed to proceed independently after passing through the most dangerous area, the homeward-bound vessels were grouped to sail in company from their port abroad. An ocean escort was provided—usually a cruiser of the older class—and there was opportunity in the longer voyage for the senior officer to drill the convoy to some unity and precision in manœuvre.
The commander of the ocean escort had no easy task in keeping his charges together. The age-old difficulty of grouping the ships in the order of their sailing (now steaming) powers has not diminished since Lord Cochrane, in command of H.M.S. Speedy, complained of the 'fourteen sail of merchantmen' he convoyed from Cagliari to Leghorn. In the first enthusiasm of a new routine, masters were over-sanguine in estimation of the speed of their ships. The average of former passages offered a misleading guide. While it was possible to average ten and a half knots on a voyage from Cardiff to the Plate, proceeding at a speed that varied with the weather (and the coal), station could not easily be kept in a ten-knot convoy when—at the cleaning of the fires—the steam went 'back.' Swinging to the other extreme (after experience of the guide-ship's angry signals), we erred in reserving a margin that retarded the full efficiency of a convoy. Our commodores had no small difficulty in conforming to the date of their convoy's arrival at a rendezvous. The 'cruising speed' of ten knots, that we had so blithely taken up when sailing from an oversea port, frequently toned down to an average of eight—with all the consequent derangement of the destroyers' programme at the home end; a declared nine-knot convoy would romp home at ten, to find no escort at the rendezvous.
In time, we adjusted our estimate to meet the new demands. Efforts of the Ministry of Shipping to evolve an order in our voyaging that would reduce irregularities had good results. The skilfully thought-out appointment of the ships to suitable routes and trades had effect in producing a homogeneity that furthered the employment of our resources to the full. The whole conduct of our seafaring speedily came within the range of governmental control, as affecting the timely dispatch and arrival of the convoys. The quality of our fuel, the state of the hull, competence of seamen, formed subject for close investigation. The rate of loading or discharge, the urgency of repairs and refitment, were no longer judged on the note of our single needs; like the states of the weather and the tide, they were weighed and assessed in the formula that governed our new fleet movements.
The system of convoy protection had instant effect in curbing the activities of the U-boats. They could no longer work at sea on the lines that had proved so safe for them and disastrous for us. To get at the ships they had now to come within range of the destroyers' armament. Hydrophones and depth-charges reduced their vantage of submersion. The risks of sudden rupture of their plating by the swiftly moving keel of an escorting vessel did not tend to facilitate the working of their torpedo problem. In the coastal areas aircraft patrolled overhead the convoys, to add their hawk-sight to the ready swerve of the destroyers. The chances of successful attack diminished as the hazard of discovery and destruction increased. Still, they were no fainthearts. The German submarine commanders, brutal and hell-nurtured, are no cowards. The temptation of a massed target attracted them, and they sought, in the confusion of the startled ships, a means of escape from the destroyers when their shot into the 'brown' had run true.
Convoy has added many new duties to the sum of our activities when at sea. Signals have assumed an importance in the navigation. The flutter of a single flag may set us off on a new course at any minute of the day. Failure to read a hoist correctly may result in instant collision with a sister ship. We have need of all eyes on the bridge to keep apace with the orders of the commodore. In station-keeping we are brought to the practice of a branch of seamanship with which not many of us were familiar. Steaming independently, we had only one order for the engineer when we had dropped the pilot. 'Full speed ahead,' we said, and rang a triple jangle of the telegraph to let the engineer on watch know that there would be no more 'backing and filling'—and that he could now nip into the stokehold to see to the state of the fires. Gone—our easy ways! We have now to keep close watch on the guide-ship and fret the engineer to adjustments of the speed that keep him permanently at the levers. The fires may clag and grey down through unskilful stoking—the steam go 'back' without warning: ever and on, he has to jump to the gaping mouth of the voice-tube: "Whit? Two revolutions? Ach! Ah cannae gi' her ony mair!"—but he does. Slowly perhaps, but surely, as he coaxes steam from the errant stokers, we draw ahead and regain our place in the line. No small measure of the success of convoy is built up in the engine-rooms of our mercantile fleets.
Steaming in formation at night without lights adds to our 'grey heires.' The menace of collision is ever present. Frequently, in the darkness, we have no guide-ship in plain sight to regulate our progress. The adjustments of speed, that in the daytime kept us moderately well in station, cannot be made. It is best to turn steadily to the average revolutions of a former period, and keep a good look-out for the broken water of a sister ship. On occasion there is the exciting medley of encountering a convoy bound the opposite way. In the confusion of wide dispersal and independent alterations of course to avert collision, there is latitude for the most extraordinary situations. An incident in the Mediterranean deserves imperishable record: "We left Malta, going east, and that night it was inky dark and we ran clean through a west-bound convoy. How there wasn't an accident, God only knows. We had to go full astern to clear one ship. She afterwards sidled up alongside of us and steamed east for an hour and a half. Then she hailed us through a megaphone: 'Steamer ahoy! Hallo! Where are you bound to?' 'Salonika,' we said. 'God Almighty,' he says. 'I'm bound to Gibraltar. Where the hell's my convoy?'"
THE THAMES ESTUARY IN WAR-TIME