This would have to be one of the longest running threads in Railpage and what we are seeing now are a number of elements being raised again but that's not a bad thing given this project is pretty much committed to go forward.
I think there are several themes or principals that have come it in the discussion overtime that I think are worth repeating again before getting into the real technical nitty gritty.
First up any new train design going forward should incorporate as much of the lessons learned from both the XPT and XPL over their life. to not incorporate those lessons learned (without embodying costly customization in the specification is very important from both a design, technical, performance, maintenance, operational and CUSTOMER service level).
There is no doubt you want a really robust, easy to maintain vehicle that is very reliable and easy to maintain. The current fleet is small. There are no specialized maintenance facilities outside of Sydney so these trains have to be good performers. Like their predecessors these trains will be intensely utilized but lets hope based on RTT's post that sufficient sets are procured to operate a much more customer friendly timetable that addresses what the public and multiple surveys have been calling for, for years.
Avoid leading edge design and over customization. At one stage the Hunter Valley DMU's were classed as some of the world's most expensive railcars because of the extreme level of customization even though the cars grew out of the classic Cummins engine/Voith transmission platform that has been used widely from narrow gauge Australind's through to Prospectors, Explorers, V'Locities, Voyager and super Voyager trains.
Where I am heading to here is now that we're getting to the pointy end of going for a real contract, its time to start moving to 1 train type and using multiple sets to manage capacity and/or enable sets to be split like Moree/Armidale and others that may emerge in the 30 to 40 year horizon that these new trains will operate in.
The improvements in noise suppression etc of new generation diesel trains like this have advanced enormously and we forget that quiet, fast, comfortable DMU's like the Prospector are 21 years old. Having essentially one "platform" in terms of an enginnering solution results in enormous capital cost and maintenance savings for this relatively small fleet.
In saying that just like the Prospector, ensure your modern but proven design is future proofed. I'll put my hand up and say that it's hard to envisage right here and now that we may have higher speed running now but over a 30 to 40 year horizon we are very likely to. Many of our existing mainlines in particular will come up for rerailing and further concrete resleepering and that combined with the impressive acceleration and braking performance of new generation DMU's means that speeds will improve especially with the introduction of additional signaling and train management systems such as being developed by ARTC. I frequently get hit over the head on this but when ARTC rerailed the Koolyanobbing to West Kalgoorlie line not that long ago speed for the Prospector was increased from 140km/hr to 160km/hr.
I wouldn't suggest for a moment that it'll be much higher than 160km/hr but it could go to 176 km/hr which seems to be where a number of railroads have headed to because after that the added infrastructure and actual rail alignment is at its limit. It's hard to picture that in Sydney but beyond the ranges there are opportunities to take advantage of the capabilities of these vehicles. The WA Prospector doesn't operate at 160km/hr everywhere. That corridor was optimized east of Northam to around the 120/130km/hr mark but the Prospector with its power to weight ratio easily takes advantage of sections where higher speed is permitted.
Therefore a new generation Explorer type train with high power to weight ratio could use that capability to recover from slow curves far better than today's XPT does and also brake much more quickly.
Flexibility around interior configuration. Modular design, built in seat rails in the floor and side sills all enable interior configurations to be adjusted over time which the current trains cannot do. It maybe possible if the market required to have hi and low density seating configurations to enable some degree of customization around medium versus long distance services.
I'd also include a much better approach to on-board catering. The current buffet cars are huge occupiers of space. If you look at what the Japanese do with trolley services its quite amazing and similarly what VIA Rail do around catering on their corridor trains is equally quite satisfactory for the style of food and beverage served. For that matter look at the size of a Jetstar Boeing 787 or A320 galley that serves everything from light meals to snacks.
Anyway it's great to see this development getting underway. Let's hope it results in a "New Deal" (to quote a 1980's Victorian slogan) for NSW.