Before the TOPS Class 97 was issued to self-propelled locomotives in departmental ( non-revenue earning ) use , British Rail had such locomotives numbered in a variety of series , together with locomotives that were no longer self-propelled .
Before the introduction of the Total Operations Processing System , Class 97 was issued to self-propelled locomotives in departmental ( non-revenue earning ) use , British Rail had such locomotives numbered in a variety of series , together with locomotives that were no longer self-propelled .