bombardier

The bombardier then checked the gyroscopic stabilization of the bombsight and clutched in the electrical motor.

Wikipedia: Bombardier (Bdr) and Lance Bombardier (LBdr or L/Bdr) are British Army ranks used in the Royal Artillery and Royal Horse Artillery instead of (respectively) Corporal and Lance Corporal. In the Canadian Forces, the Artillery Branch uses the ranks of Master Bombardier and Bombardier instead of Master Corporal and Corporal.

[…] the officer to whom the command was deputed, to the amusement of a German bombardier, ordered one of the largest cannons to be placed under the gate of a fortress […]