I suppose the assumption about the capacity of the crossbench cars was easy - eight compartments, each seating ten and standing six = 128. Maybe cramming an “official 80” standees on an R was a way of claiming the new cars could move what the old cars could move, and they jiggled the formula to be 56/72 on the R1s.
I also wonder if the assertion that the corridor cars were regarded as second tier cars was always the intention, as tender specs for MU operation were included but rejected due to cost. It would have been interesting to listen in to the discussion on the tender selection committee, with the traffic branch pushing for MU cars and the treasury gnomes insisting on the lowest price. Maybe the second tier idea emerged after MU operation of these cars was rejected.
They knew that the safety of conductors working footboards on crossbench cars was an issue that would eventually end the practice, which was the motivation behind the PR1 program to convert relatively new P cars to the corridor design. There was even a corridor conversion drawing produced for O cars, whether seriously considered or just a design exercise is now hard to fathom. I think it’s reasonable to assume though if there’d been an unequivocal decision to retain and upgrade the tramways and acquire all the 250 postwar R1s ordered the PR1 program would have been pursued to give a fleet of 750 corridor cars by the mid 50s, with future acquisitions beyond that ranging in options from development of the existing design with power doors and resilient wheels, to going for a new design. Maybe the route to PCC operation might have been by what the Dutch and Belgians did, use second hand US equipment fitted to locally built bodies, given the restrictions on currency exchange with US dollars at the time.
Who knows - if Fergus Maclean hadn’t died when he did, if the NSW tramway design office hadn’t been shut when it was, if the politics of the day hadn’t been so in thrall to the road lobby and the expressway delusion things might have turned out
> On 11 Oct 2017, at 4:18 pm, Mal Rowemal.rowe@... [TramsDownUnder] TramsDownUnder@...> wrote:
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> On 10/10/2017 9:46 PM, Tony Gallowayarg@... mailto:arg@aapt.net..au [TramsDownUnder] wrote:
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>> Os, O/Ps and Ps were rated at 80 seats, 48 standing, Rs had 48 seats with 80 standing, R1s 56 seats, 72 standing. So all nominally had a crush load of 128 passengers. PR1 cars had one less row of seats than an R1, being shorter, so seated 52 passengers and took about 70 standees.
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> That makes an interesting comparison with the Melbourne SW6 - which had either 48 or 52 seats and was rated for a crush load of 180.
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> Either Melbourne commuters were statistically smaller or the seating layout of the SW6 allowed more standing room. The lack of end platforms may also have given more space. I wonder if the official R class crush loads included standees on the end platforms?
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> I have attached a plan of the initial SW6 design - which had four double tip-over seats in each saloon. This choice may well have been influenced by the R design.
> Later SW6s replaced the tip-over seats with fixed seats, making space for the longitudinal seats just inside the saloons to become triple seats and thus increase seated capacity from 48 to 52 without changing the rated crush load.
> Knowledgeable fans always liked the SW6s with tip-over seats.
> I think all were converted to fixed seating over time.
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> One feature of the R and R1 design that Melbourne would have been wise to adopt was the side windows - the sliding plate glass in Sydney is a much better and more reliable design than Melbourne's 'half drop' windows in theSW6s and later Ws.
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> Mal Rowe in a city that was very proud of the SW6 design
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> <SW6-plan_tipover-seats_MMTB.jpg>