flag lieutenant

He would go up on the bridge with the Flag-Lieutenant, and the ships would be cleared for action.

"It's the French instructor, I believe, sir," said the flag-lieutenant.

Somehow there was no conveyance in waiting, not even a rickshaw, so Maynebrace and his flag-lieutenant had to walk.

Bidding his flag-lieutenant go on to Elizabeth Castle whither they were bound, and await him there, he crossed over to Jean.