Definition of "chargehand"

The most surprising thing was to discover that each job had its little tricks, peculiarities that had been learned in the experience of years, and one of the really pleasing features was the unlimited patience and kindliness of the chargehands and fitters, who would go to great lengths to teach the budding engineer all they themselves knew.

1944 September and October, A Former Pupil, “Some Memories of Crewe Works—I”, in Railway Magazine, page 283