66s on sleepers

[Hammerton]

Sorry if this is a topic elsewhere but I couldnt find if it is....why are the 73/9s currently doubled up with a 66 in Scotland. All 3 destinations seem to have a 66 with a single 73. This cant be a traction issue on 5 coaches.

 

[JonathanH]

Sorry if this is a topic elsewhere but I couldnt find if it is....why are the 73/9s currently doubled up with a 66 in Scotland. All 3 destinations seem to have a 66 with a single 73. This cant be a traction issue on 5 coaches.

The suggested reason is that there are only three fit 73s (out of six). Clearly when this happens only having two 73s would mean cancellation of one of the services. To play safe, the 73s are switched to supply ETS and act as translators for coupling purposes and 66s provide traction.

Once back up to four fit 73s, the 66s can come off.

The Aberdeen portion is running with only four coaches which is a rather light load for the 66.

 

[Hammerton]

The suggested reason is that there are only three fit 73s (out of six). Clearly when this happens only having two 73s would mean cancellation of one of the services. To play safe, the 73s are switched to supply ETS and act as translators for coupling purposes and 66s provide traction.

Once back up to four fit 73s, the 66s can come off.

The Aberdeen portion is running with only four coaches which is a rather light load for the 66.

Thanks, i can see the logic but the Fort Wiliam and the Aberdeen would be single locos in any case. Is it a case of protecting the 73s as they are so fragile. What is the issue with them

 

[XAM2175]

Thanks, i can see the logic but the Fort Wiliam and the Aberdeen would be single locos in any case. Is it a case of protecting the 73s as they are so fragile. What is the issue with them

The 73/9s are the only diesels that can couple directly and supply power to the Mk 5 coaches, so yes they do have to "protected" in that sense. I don't know if there's any specific issue at the moment, though.