BiggAW wrote: The study seemed to favor DMU's, even though they are totally unproven, and there wouldn't be any used ones available.There's thousands of DMUs in use around the world, and quite a number of them in use in the US. The new ones in use in Southern NJ, etc, are about as reliable as you get for a railcar.
It cited noise and vibration as a big problem with locomotives.Poor designs or antiques, maybe. NJT's PL-42s aren't very loud at all.
On a side note, GE will be coming out with hybrid diesels that basically work sort of like a Prius with the dynamic braking energy stored for use during acceleration, and these could solve some of the efficiency and noise problems that plague the current generation of big diesels, and would likely prove perfect for commuter rail.There's no efficiency problem with current diesels, it's just you lose out when you have 300,000 lbs and 3x 100,000 railcars, vs 3 DMUs. And there's plenty of quiet diesels out there - as hated as the PL-42s are, they are a fairly quiet unit...
And a hybrid? Talk about unproven technology - nobody's ever run one in service...
Although the report didn't explicitly say so, acceleration out of stations like Wallingford would probably be significantly impacted if the current GP-40's or P40's were used on this service because of their noise and vibration profile.About the only way to get a P40 to accelerate fast is to toss it off a cliff, and even then it'd likely hover a few seconds before starting to slowly fall
Seriously though, it's not an issue of the locomotives, it's a simple issue of power to weight ratio. DMUs and EMUs have a far better one, and that means they're faster.
Realistically, I think everyone's counting chickens before they hatch - and despite all this talk of big stimulus, it boils down to a simple reality: The government doesn't have any money to spend in the first place, and everyone wats their piece anyway.