Could use a few “rivet counters” on this one with somebody who might know an exact detail of when. Having worked for real railroads, there are many things that escape you or get by that a “modeller” would consider unusual and pay attention to.
I recently got the Athearn Genesis Tank-Train set (the 2 end units and 10 middle cars). Great job, looks nice I want to get another set on the re-run. I took the set with the “billboard” lettering original scheme with the orange and white symbols along the car bodies.This reverts back to I presume the early 70’s when the train and concept first appeared.
What puzzles me is the cars come with plastic “shelf couplers” which for this era don’t seem to be correct. I am not sure, but didn’t the shelf coupler come along later in life like the 80’s into 90’s railroading??? Can anyone come up with a definite answer, as if so, I’d like to remove them and use regular type F knuckle couplers as my railroading is mainly 1960’s but will stretch to the pre-early Amtrak era of no more than 74 or 75???
I’m no expert here, but shelf couplers have been around for a long time. Passenger trains used them a lot, for instance. For freight, the first applications were to specially sensitive tank cars AFAIK and I think that goes back to at least the 60s? The much more widespread use is as you noted, more recently due to more stringent requirements. Couplers tend to pierce tank bodies in derailments, so keeping tank cars coupled to those next to them helps reduce this risk as a factor.
My guess on the T-T is that it was hoped they would limit the potential for a minor derailment from damaging all the inter-car piping, etc and reduce the potential to spill the cargo in all derailments, since oil was already a sensitive subject in California when these went into service.
Dug around a little more on the history of the Type F shelf coupler standard. Yes, it was adopted as THE standard in 1970, so was required by DOT/FRA for certain applicatiosn at that point. However, it had earlier been adopted (1954) as an AAR “alternate standard.” It was origianlly introduced in 1943, so does go back a way. I’m uncertain how many cars may have received them between 1943 and 1970, but believe these were primarily chemical tankers.
Another benefit for the standard was that it significantly reduced slack action, something generally beneficial from a maintenance and loss control perspective.
I can’t quote you an exact date but even though those couplers had been around for a while, their use really took of around the time (I think maybe early 70’s) when the A&S in E ST Louis and the Wabash (N&W) at Decatur had tank car drawbar over-ride accidents that resulted in catastrophic explosions in their yards. This was when the tank car head shields became a big issue too.