Currently, the time allocated for the Darling Harbour route off peak is 59 minutes, from departure at Circular Quay to arrival at the Quay on return. Under the new timetable, this is reduced to 55 minutes, even though there is one additional stop - ferries will stop at Barangaroo in the inbound and outbound direction. They now stop at Barangaroo only when outbound from Circular Quay.
It may be argued that the new vessels operating the route - the Emeralds - have the extra speed and acceleration needed to shave four minutes off the journey compared to the slower First Fleeters now used. It is true the Emeralds will be faster between McMahons Point and Balmain East where there are no speed restrictions, but I'm doubtful they will always be able to complete the round trip in 55 minutes:
- speed restrictions of 8 or 15 knots are enforced over most of the route, so in these sections the Emerald boats will not have a speed advantage;
- there is no evidence yet that the Emerald Class is more manouevrable than the First Fleeters. They appear to me to be less manouevrable, lacking the twin rudder feature of the older vessels, so berthing the new boats at intermediate stops may actually be slower;
- the extra stop at Barangaroo will add at least two or three minutes to the running time;
- the new timetable has departures from Balmain East to Circular Quay and to Barangaroo scheduled only one minute apart. This creates a conflict, unless one vessel berths on the western side of the pontoon. This too will have a small delaying effect.