#didsburydoubles – What might it take to put doubles back on the Didsbury line?

I’m a transport geek. I find stuff like timetables absolutely irresistible.

So thanks to the working timetables exposed in the FOIA request I took a look over lunch to find out what extra resources would be required to provide double trams once again on the Didsbury line.

Firstly, the notionally “busier” Cross-City services – the Didsbury-Shaw trams.

The Didsbury-Shaw 12 minute frequency service requires 12 trams on a circuit to operate it – i.e. it takes 144 minutes for one tram to complete a full round-trip.

There are two Metrolink depots, the original one at Queens Road, and the newer and larger depot at Trafford.

The duties for the Didsbury-Shaw service are split between the depots, 5 duties are provided by Queens Road, and 7 by Trafford.

So, to increase all the Didsbury-Shaw trams, that would require all 12 duties to be double trams, an extra 5 trams provided by Queens Road, and 7 from Trafford.

I don’t know what sort of spare resources Metrolink has around. I can usually see more than 8 trams sat stabled at Trafford depot when I go past in the morning – though I accept they could be stopped due to a fault or awaiting scheduled maintenance such as a planned servicing.

Secondly, the Didsbury-Deansgate service.

This is a much simpler operation, composed of 4 single-tram duties from Trafford depot, on a self-contained “shuttle” operation between Didsbury and Deansgate.

It is therefore theoretically simpler to double, requiring an additional 4 trams to be supplied from Trafford.

To provide double trams on both the Didsbury-Shaw and Didsbury-Deansgate services would require 16 extra trams to be available for traffic.

We’ll assume providing all 16 trams is a non-starter, that Metrolink simply don’t have 16 spare trams available on a daily basis for the moment.

There are three options, as I see them, assuming no significant service changes:

• The least resource intensive is for Trafford to provide an extra 4 trams each day and convert the 4 Didsbury-Deansgate shuttle duties to double trams.
• The other is to double all the Didsbury-Shaw duties, which requires 12 extra trams, a somewhat tougher ask.
• The slightly more radical option is to cancel the Didsbury-Deansgate shuttle, and revert to a 12 minute headway. Use those 4 released trams to strengthen 4 of the Trafford Dids-Shaw duties, only requiring a further 8 trams to be provided, 4 from each depot.

Right now, it seems that the path of least resistance and possibly most rapid solution is for Didsbury-Deansgate trams to be doubled. It feels less than ideal, as the notionally busier trams are the Cross-City ones. But this might at least encourage some passengers to choose to change at Deansgate rather than wait for the direct tram and alleviate some pressure on the Didsbury-Shaw.

However, I feel all doubles on a 12 minute headway used to work okay before. Do we want to go back to that?