Following this discussion with some interest, I'm wondering if using more current technology would be a cheaper better solution. I'm thinking autonomous driving engines. It could be much simpler and cheaper than this PTC. They already have self driving cars. It would be much simpler to implement for railroads. The tracks don't change. The routes are known. There is no steering involved. No other vehicles to worry about other than possible obstructions on the track. All you can control is the speed. Much easier than a self driving car.

So if the cause was situational awareness, with an autonomous driving engine, the engine would have known about the 30mph curve before it ever left the station. That's the engine would have known. Who cares about the engineer. But if you just used the system as an assist to the engineer imagine having a screen in the engine with a view of the track (possibly zoomed). As you are going down the track you get these warnings on the screen.

5 miles, 30mph speed restricted curve
4 miles, 30mph speed restricted curve
3 miles, 30mph speed restricted curve
2 miles, 30mph speed restricted curve
1 mile, 30mph speed restricted curve
Initiating braking, failure to slow for 30mph speed restricted curve

When you stop and think about it, a lot of driving a train is cross your fingers, especially the faster you go and the longer the stopping distances become. I was curious about the cab in high speed trains and what they may have for seeing further down the track. But after watching this video, Rotterdam-Antwerpen 300 km/h, Thalys cab ride / cabinerit, https://www.youtube.com/watch?v=9Vm8_l5oye4, it occurred to me, looking out the window is optional. If you did see an obstruction or problem with the track, by the time you saw it, the ability to do anything about it was 20, 30, or maybe 60 secs or more ago. So unless you can time travel, looking out the window is just for your entertainment. You're relying on your signals and have your fingers crossed.

When you realize that, might as well let the train drive itself or at the very least greatly assist the engineer. I thought of the idea of using a forward looking camera with a screen in the cab and then you could have speed dependent zoom. The faster you go, the more zoom you get. But the physical problem of curves and going over rises negates some of it's usefulness.

Never having gone for a cab ride in a steam engine, but after sitting in one, my first thought was, how the heck do you see where you are going? And then I wondered on what you do on left hand curves? Somebody said that's what the fireman is for. Now that the technology exists, would it be worth the cost to implement a camera system? Camera mounted up front, screen in the cab and using speed dependent zoom. In the preservation community and the use of part time, or even once in a while engineers, would it increase safety? How about you're looking out the window, see something and have the ability to glance over and see a zoomed in view? Or even don't bother with looking out the window, just watch the zoomed in view. Considering stopping distances, isn't the further you can see down the track better?

https://www.reuters.com/article/us-washington-train/amtrak-engineer-misread-signal-before-fatal-crash-near-seattle-u-s-agency-idUSKBN1FE2NH

In the five weeks preceding the derailment, the engineer had qualified on the Point Defiance Bypass section of track following the completion of seven to 10 observational trips in the locomotive as well as three trips operating the equipment, two northbound and one southbound. [emphasis added]

It includes facts like this:

The ONE southbound student trip seems to confirm what most here believe; the guy was lost on the territory.

This newest version of events leading to the derailment is quite different than what the NTSB told us in their first version.