Monday, July 09, 2007

Harmonised headways

Having routes to operate at mutually compatible intervals ensures easy interchange between services and reliable travel times.

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1 comment:

Peter Parker said...


I didn't mention any bad examples, but Sunday services to Northland Shopping Centre certainly qualify.

As trains in the area run every 20 minutes, harmonised services would need to be either every 20, 40 or 60 minutes.

Actual frequencies for the Sunday routes serving Northland are as follows:

251: 40 min
555: 45 min
556: 45 min
527: 50 min
517: 55 min
566: 55 min
563: 70 min

In the above cases, the slightly better frequency of 50 or 55 minutes over hourly are more than offset by the inconsistent connections and lack of clockface times.

Similarly 45 minute headways cannot work with 20 minute trains, and a 40 minute service is vastly better even if the route has to be changed.