The Blocking of Zeebrugge

by Alfred Francis Blakeney Carpenter

To mention a few of the items: Separate orders for the oversea voyage were required for each squadron destined to make the passage independently of the remainder. Others were needed for the voyage of the main force, others to cover the aerial attacks and the long-range bombardments. The supporting squadrons must have their instructions. Still further orders were designed to deal with the period of "approach." Then there were those for the main attack on the Mole, for the demolition work, for the destruction of the railway viaduct, and for the proceedings of the artificial-fog craft; also those for the blockships and the rescue work. The retirement required its own share. Even now we have not mentioned those designed to meet possible eventualities, such as encountering enemy vessels en route, or returning to harbour if postponement of the enterprise was necessary.

Having decided where and how things should be done, the remaining question was when they should take place. The operation with its various phases and diversions could not be carried out on the go-as-you-please principle. Every item needed to be carefully fitted in to suit the remainder. The timing of each event was of paramount importance. A long-range bombardment or an aerial attack, if delayed, might destroy our own vessels. The blowing up of the viaduct was calculated to render hors de combat all human beings within a certain distance—our own men on the Mole must not be endangered by it. It would be useless for the blockships to arrive before the fire of the Mole batteries had been suitably diverted. Aerial bombers flying at a hundred miles per hour could not accompany the ships steaming at about one-tenth of that speed. The line of fire from the bombarding vessels could not very well coincide with our approach course, hence the necessity for the monitors to take up independent positions. And so on. How could a satisfactory synchronisation of events be arranged?—that was the problem.

There were only two methods to consider: firstly, that of centralised command by signal; secondly, that of working in accordance with a prearranged time table.

The former method was obviously impracticable. Signals passed by either the wireless or visual method, during the approach, would make our presence known to the enemy and thus preclude all chance of taking the latter by surprise. After the attack had commenced signals would be impracticable for obvious reasons, chief amongst them being the deafening noise and the presence of artificial fog. So direction by signal could be ruled out.

The Timing Question

Recourse was had to the time-table method. A table was made out showing the exact times (by clock) that the main force was to pass through various positions and to arrive at the several destinations. All other movements were to synchronise according to plan. The time table naturally varied for each day according to the projected time of arrival of the blockships, this, in turn, depending on the time of high tide. But that was not all. It was necessary to guard against unexpected delays due to accident, and against vagaries of the tidal stream. Every unit should know, at a late stage of the oversea trip, if the blockships were likely to be late or early, and the probable difference between actual and projected time involved.

We would not be satisfied with the degree of punctuality usually associated with certain railways. A few minutes out, one way or the other, might be serious; an error of half an hour would probably be disastrous. But the oversea passage involved a journey of approximately a hundred miles for the blockships and storming vessels, though rather less for the Dover contingents. That fact, combined with the usual unwieldiness of a fleet comprising over one hundred and fifty vessels, was not likely to render punctuality very easy of attainment. The disadvantages of daylight made it inadvisable to leave our bases extra early for the sake of having plenty of time to spare. Careful calculations were necessary and the resulting time table was circulated to all concerned.

Before leaving this consideration of the timing question it may be of interest to mention that the storming vessels were to be twenty minutes ahead of the Zeebrugge blockships on arrival in the vicinity of the Mole. In that twenty minutes we were to get alongside and land the storming parties; the latter were to take the necessary steps to put the batteries out of action as far as the safety of the blockships was concerned. At the expiration of the twenty minutes the blockships were to pass round the end of the Mole and make their dash for the canal entrance. The reader may wonder why twenty minutes was the chosen interval. Too long a time might allow the German defences to recover from the initial surprise; too short a time might not enable the storming vessels to complete their work before the blockships were seen by the enemy. Twenty minutes, short though it was, was chosen as a compromise.

All this operational staff work was carried out at Dover under the direction of the Vice-Admiral, who, as previously stated, was already overloaded with duties and responsibilities arising from the work of the Dover Patrol.