A thought has occurred to me recently about the above units, all of which are of course 2-car suburban.
The most important usage of all of these was presumably to boost capacity in the peak or shoulder-peak, working with 4EPBs, 455s and 465s respectively, so that 4-cars could become 6 and 8-cars could become 10.
Was there, thus, an issue whereby these classes accumulated lower mileage than their corresponding 4-car equivalent?
Or were the diagrams designed to ensure that all were kept out off-peak?
In some cases, did this lead to some services being longer than required (e.g. some 6-cars running round all day when a 4-car could have sufficed) in order to keep the mileage up?
Or was there some clever diagramming by which, and by design, pairs of 2EPBs, 456s and 466s ran around all day? Haven't seen any 466 pairs though I have seen pairs of the other two.
Or was it just accepted that these classes would accumulate lower mileage?
In all cases I'm thinking of the eras when the units were still relatively new or mid-life (or at least not under threat of withdrawal), so thinking of say the 1960s-80s for the EPBs and 1990s-00s for the 456s and 466s.
The most important usage of all of these was presumably to boost capacity in the peak or shoulder-peak, working with 4EPBs, 455s and 465s respectively, so that 4-cars could become 6 and 8-cars could become 10.
Was there, thus, an issue whereby these classes accumulated lower mileage than their corresponding 4-car equivalent?
Or were the diagrams designed to ensure that all were kept out off-peak?
In some cases, did this lead to some services being longer than required (e.g. some 6-cars running round all day when a 4-car could have sufficed) in order to keep the mileage up?
Or was there some clever diagramming by which, and by design, pairs of 2EPBs, 456s and 466s ran around all day? Haven't seen any 466 pairs though I have seen pairs of the other two.
Or was it just accepted that these classes would accumulate lower mileage?
In all cases I'm thinking of the eras when the units were still relatively new or mid-life (or at least not under threat of withdrawal), so thinking of say the 1960s-80s for the EPBs and 1990s-00s for the 456s and 466s.