I think it is time to standardize platform heights for all trains, at least in North America. Creating a standard track gauge has been extremely beneficial to the rail network, as it allowed any piece of railroad rolling stock to go anywhere in the system. I think similar gains are to be made by creating a standard platform height for passenger cars.
In the United States there are many platform heights used. The best height from a passenger's point of view is the 48-inch height, which allows for level boarding into a single-level passenger car:
The trouble is, this means the platforms have to be extremely close to the tracks in order to avoid having dangerous gaps between the platforms and the passenger car. This means there is little or no clearance for freight cars, which can be wider than passenger cars. Also, a faster moving train has a wider 'dynamic envelope,' which means it can bounce around more, increasing the likelihood of it scraping the platform as it rolls past.
These two considerations mean that outside of the Northeast Corridor, most platforms are much lower - usually either flat with the rail or 8 inches above the top of the rail, to avoid wide freight cars or fast-moving trains (freight and passenger). Lower platforms mean that passenger cars need to be equipped with their own stairwells:
Stairs have their own problems. They make loading and unloading passengers much slower, and for passengers with disabilities, it means special lifts need to be installed on either the train cars or the platforms in order to raise the person up to the car height:
To get around these problems, car designers outside the Northeast Corridor have changed the design of the passenger car to have a lower floor. Amtrak's Superliner cars, for example have a floor height of eighteen inches above the top of the rail, meaning for a platform height of eight inches there would be only one 10-inch step. For platforms flush with the tracks, an 8-inch stool can be used to create the same step increments:
Only one city I know of has an 18-inch tall platform to be level with the Superliner cars, and that is my home town of Salt Lake City, Utah:
... and the only reason they can do it is because those are dedicated tracks for Amtrak. No other trains use them except for an occasional UP Executives train - pulled by diesels - and they have a very awkward step down onto the first step of the passenger car's stairwells, which are designed for an 8-inch platform height. When Union Pacific's steam locomotives come to visit, they cannot use these platforms either because the driving rods of the locomotive would scrape against the 18-inch tall platform.
Other commuter rail cars with a similar strategy exist. Bombardier's Bi-level cars have a floor height 25 inches above the top of the rail, which requires two steps for passengers boarding from an eight-inch tall platform:
Of course, both of these heights - 25 inches and 18 inches - still don't do anything to help passengers with disabilities. Special 'high block' platforms must be constructed in addition to the regular 8-inch platforms in order to be fully accessible:
And, as you can see, these high-blocks are placed father back so that they don't interfere with fast trains or wide freight cars. The commuter train has to line up perfectly with the high-block as it stops (causing station stops to be done slower) and the conductor will need to lay down 'bridge plates' to make a flat surface for a wheelchair to roll onto the train, which also takes time.
Sidenote - my hometown provides another exception in the UTA FrontRunner, which uses a 25-inch tall platform for all doors in its bilevel fleet, which I think is also unique:
One serious problem all of these cars of non-standard floor heights face is that once a passenger with disabilities is on-board the train, they are restricted to that single car, since there are stairs within the train car that must be traversed in order to move between cars. A passenger with disabilities cannot go from a coach car to a dining car, for example. So this solution is really only viable for commuter trains, or trains designed for shorter journeys.
Another approach has been to keep the passenger cars standard, but to use a 'gauntlet track' to either move passenger trains closer to the tall platform, or to move freight trains away from the platform:
This solution is very effective, but is costly since it involves extra track infrastructure to construct and maintain. Also, trains entering the 'gauntlet' must slow down, which decreases efficiency.
A less-common way to have a high platform and no gauntlet track is to have deploy-able platform extensions. These extend when a passenger train is scheduled to arrive, and retract when a freight train or a fast train needs to pass:
But again, like the gauntlet tracks, this solution relies on fixed infrastructure. If a train is going to make 10 stops along its route it will need at least 10 gauntlet tracks - perhaps 20 if it travels on separate tracks in each direction. If that train has 4 doors that open at each station, then there will need to be a total of 40 platform extensions - 80 if it uses the separate track.
All of this adds cost to a system. If only there was a way to eliminate any need to improve the
infrastructure and instead incorporate such an extender into the
vehicle...
----*----*----*----*----*----*----*----
The Solution:
Siemens has developed a deployable gap-filler, which is now in service on Florida's BrightLine:
• Video Link
These allow for high platforms to be built directly on the mainline without need for gauntlet tracks or platform extenders, and freight trains can roll through these stations at full speed:
(skip to 20 seconds into this video)
• Video Link
This solution solves
all the problems with platform heights. There don't need to be any infrastructure improvements. There don't need to be any special tracks for station platforms. There don't need to be wheelchair lifts, steps, or high-blocks. The only moving parts are contained within the train cars, so they can be actively maintained at the same schedule as the doors themselves.
I propose that every new passenger rail system be designed to use high-platforms, 48-51 inches tall, and use active gap-fillers to make every platform a level-boarding platform.
For busy rail corridors, bi-level cars can still function at high-level platforms, such as New Jersey Transit currently uses:
Another way to do bi-level cars is to go straight up, where space allows it. This would mean that passengers with disabilities could still move between cars easily on the bottom floor, and the top floor could be used for observation areas, just like in the Colorado Rail Car
Ultra Domes, which are 18-feet tall (meaning they can go anywhere a double-stack container train can):
Most importantly, Siemens - the manufactuer of the Brightline cars - is set to manufacture
137 cars for Illinois and California for corridor service, replacing an order for bi-level cars. These types of passenger cars are also well-situated to be the car-of-choice for Amtrak's next long-distance fleet, replacing older cars on their long-distance trains. If these cars become that ubiquitous, it would be extremely easy to include the same gap-fillers in all these new cars (or retrofit them into existing Siemens cars). This would create a national standard platform height and eliminate all of the complicated and less-effective solutions that have been deployed throughout the non-Northeast Corridor parts of the country.
For more reading on how complicated platform heights can be, read this post of the Caltrans HSR Compatibility Blog:
http://caltrain-hsr.blogspot.com/200...VN24vHSWVqM2VM
Let's standardize passenger equipment in the USA! It can be done, and the benefits will be worth the pain!