Looked on the cover of latest Trains Magazine - yep it’s January. But inside index page explains the pix on the cover as “As an Amtrak protect engine stands ready”…see my question?
I don’t understand your question. The inside uncropped picture shows: Amtrak 933 on the Protection track, NJT’s Cab car 5016 leading toward the station platforms from the Hudson River Tunnels, and LIRR MU set coming down from the West Side Yard. July 4, 1997 basically no different than July 4, 2007 or November 29, 2009.
{?}…To respond to that question…{I think}, my opinion would be a “stand by” power unit in all that maze just in case a failure of another occurs, the “stand by” could connect and move disabled train. That’s just my opinion.
Ok. A protect engine is just that: an engine placed to be used in an emergency to protect schedules, etc. Commuter lines, especially electric ones, will often place a diesel at certain points or yards, in case there is a problem But, come to think of it, this brings up an interesting point. The Amtrak “protect” engine shown is electric. To be a true protect engine it should be, or one would think, a diesel to rescue the electric trains in the tunnels in times of power failures, downed wires (too often an occurrence), etc.
I’m guessing, but it could be a perfectly accepted practice, To avoid a fouled terminal and late departures during an acceptionally heavy traffic period.
I know FedEX used to maintain a ‘Hot Stand-by’ aircraft at their hubs to cover an aircraft failure, to avoid a missed sort schedule. (A Hot Stand-by is a crewed, fueled,ready to fly, available aircraft). It would be dispatched to cover a potential failure to deliver on schedule/missed sort on a truck route–read that as being a very expensive, effective solution, charged to the offending carrier!
Thank you all. That was a pretty simple explanation. I was all set for something very convoluted; special tracks, special area, or “guarding” something important. Guess if they would call it a backup, there would be no need for a question?