justalurker66 wrote: ↑Mon Oct 16, 2023 11:56 pm
GP30M4216 wrote: ↑Mon Oct 16, 2023 8:58 pm
Is there a reason they didn’t just have the gauntlet be the passenger loading track in this case, Aka the straight rail is the freight track away from the platform and the diverging move is the alignment up to the platform? Since all trains taking passengers stop at Ogden Dunes, this would have saved some work and $$ having to job everything over a couple feet…or even a couple inches!
The original platform gauntlets were built that way. Experience showed that trains could run faster on the straight track. East Chicago was rebuilt a few years ago, Hegewich is scheduled to get the gauntlets flipped this year, Hammond's new station will have the gauntlets built to the new standard along with all the new DT-NWI gauntlets.
Yes, even though the passenger trains are coming in for a stop, they can run faster if they are on the straight track. The new gauntlet switches in rural areas are high speed switches which allow trains to pass faster. With freight trains limited to 35 MPH the gauntlet does not slow them down. Express passenger trains would have a few seconds delay, but overall having the straight track at the platform is a better option.
The new #20 turnouts at Hegewisch, Miller, Ogden Dunes and Dune Park have a 40 MPH diverging speed. The fastest a freight can go on the SSL, excluding lite engines, is 40, so taking the diverging route is not a speed penalty.
The #15s at Hammond, East Chicago and Michigan City likewise do not impose a speed penalty on freight due to existing geometric restrictions on nearby curves. Those are 25 MPH on the diverging route.
The diverging route into the platform was originally chosen as the cheaper option and worked ok in the pre-PTC days when train crews could dive bomb into speed restrictions. However, PTC would start slowing trains down for East Chicago a mile in advance, for instance, adding lots of time to get over the road. Therefore the need to flip the gauntlets became obvious. Plus the bigger turnouts make it possible to not encumber freight at all.
When the gauntlets were originally installed at Hammond, Hegewisch and East Chicago, the SSL hadn’t yet gone to #20s as standard yet, except at CPs 58.1, 54.0 and 47.5, which were the ends of Double Track segments. It was only later that the #20s came to 73.8 (wholly new CP in the early 2000s) and replaced the #10s at Parrish 64.9, Clark 61.5, Paul’s 51.5, Tremont SDG and Tamarack SDG. After West Lake, Double Track and the Hammond/East Chicago upgrades, the only remaining #10s on the mainline route will be at State Line 69.2 (space constrained), Shops 32.2, Birchim SDG, Olive SDG and Grandview.
Express passenger trains simply take the platform route now at the new gauntlets.
Side note, Metra has yet to join the big turnout bandwagon. Almost every turnout on the Metra Electric is still a #10, making crossing over agonizing. Here’s hoping they will discover the magic of a #20 someday.
