Explosive Charges
Of crucial importance were the decisions concerning the fixing and fusing of Campbeltown’s main explosive charges. Placing the charge where it would do the most damage, when it was not known how deformed the bows would be by their impact with the caisson, was problematic, as was exploding the charge at the most advantageous moment.

Lieutenant Nigel Tibbets RN, the officer appointed in charge of Campbeltown’s demolition, proposed that the ship be scuttled immediately after ramming and that her charge be exploded while she rested on the bottom, several hours after the force had cleared the area. The charge would be fixed in place before sailing, fused en route and completely sealed to guard against interference.

In the outcome the explosive charge was placed immediately abaft, or behind, the steel column that supported the ship’s most forward gun, on the argument that this was the first obstacle of strong resistance to the momentum of the ramming impulse.

The charge was made up of twenty-four Mark VII depth-charges, as used for attacking submarines, weighting 400 pound each, so that the total charge weighted four and a quarter tons. It was enclosed in a special steel tank on top of the fuel compartments and cemented in. The fuses used were the Army’s new long-delay ‘pencil’ fuses set to act after eight hours, at least three being inserted in the charge, and the whole connected together with cordtex.

© J.G. Dorrian, 1995