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Tyson--I can answer a couple of items you brought up. First, HEP cars are useful if you have to press a locomotive into service that does not have a generator (most of these now are, of course, freight units in the US and I suspect Peter--M636C--or you can tell us if such is the case also in Oz). Second, one of the drawbacks of HEP is that the number of active pax cars in the consist is limited by the current-carrying capacity of the cables and plugs between the cars (which gets mimicked by the through cables on the cars themselves). Obviously, the generator capacity is an issue, but these are usually overdesigned for safety's sake. The cable between the HEP source and the first car sets the limit. If the train's pax consist exceeds the rating of the cables (usually given by the RR as a maximum number of cars rather than the equivalent electrical values of KVA or Amperes), then to operate the electrical systems in all the cars you have to separate the consist's electrical system in the middle of the train (to balance the load) and put either another locomotive or an HEP car on the rear end . And, as you deduced correctly, a heavy load like an all-electric diner will reduce the number of cars you can power from one end of the train. Under those conditions, you cannot connect the two halves of the train together, even if you could synchronize the two HEP generators (an absolute necessity if there is more than one AC generator), because loss of one HEP unit would drastically overload the other, tripping it out and likely damaging the electrical systems in the cars closest to it, where the greatest amount of current flows. Think of it like a tree where the generator is the root system. The trunk has to be the biggest part because nutrients have to flow through it to the entire tree, and then the branches get progressively smaller and smaller., the farther away from the trunk you get. As to manpower, it's a work rules issue, like it or not, efficient or inefficient. 45144 makes an excellent point as to efficiencies. That was my point as well. I have literally seen it take from 1/2 hr to 1 hr and a small army to do a simple break, switch, reconnect move on an ATK consist, where the pax are stranded on the train with no power, A/C or lights. This was SOP on 21/22 at SAS for years, with the thru cars. It ranks along with the operating crews filing for and getting an extra full day's pay for a 5 minute setout of PV at an intermediate station where there is no switch crew. Even my highly valued and respected late old friend Charlie Luna of UTU fame couldn't explain the base economics of that to me. His answer, quite correctly, was that it all came down to what you could negotiate. As I said, logic is futile. Now, that said, in all fairness, it can occasionally take a couple of people to get a balky HEP cable unplugged. These things are big and heavy (see the load discussion above as to why), they get banged around and exposed to rather extreme climatic conditions on occasion, and occasionally they fight back. That's another good reason for operating push-pull where short turns -or work rules, for that matter - are an issue. There are very few movements quicker than the operator getting off and changing ends. Even 45144's expedient and optimized switching move can't beat the time. Plus you can do it anywhere. You don't have to spend the money for a runaround track. This is particularly important in the US, where most of the passenger-related physical plant, that allowed such things even as short as 30-40 years ago, is history and would have to be rebuilt at 10-20 times the cost of what had been there and got torn out. A good example of this in the TX end of the world is Dallas Union Station, which had 10 active tracks, plus express tracks. The City Fathers tore out all but 3 and replaced them with a parking lot for the buses that never came. Now with the LRT lines and TRE, guess what are getting put back in at substantial cost? I often wonder if we're doing the same thing to too much of the freight plant. Admittedly there are a lot of branches needing pruning, but I submit that it's a simple medical fact that a simple rhinoplasty is very different from lopping one's nose off to spite one's face-even though both can be correctly and literally classified as nose jobs. People generally tend to be cursed with a lack of foresight, and those who have it are generally kicked off the island. Off the soap box.[soapbox]
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