Railway

Railway is the buildable structure which trains run on. Railways connect Train stations and form a logistic network besides belts and optional automated wheeled vehicles. As Railways have superior throughput advantage and use relatively low CPU over multiple parallel Conveyor Belts, they are almost essential for construction of megabases.

Theoretical maximum throughput
As there is currently no hitbox for the trains, and train can clip through each other without collision, this means a busy railway can have infinite item throughput.

In case the trains have hitboxes, then the maximum throughput would be: Assuming an infinite-long cargo train runs on the flat, horizontal rail at max speed of 120 km/h.

For items stacks to 100, such as ores, this is equivalent to This is equivalent to the throughput of 512 Conveyor Belt Mk.5.

Although the train can move this amount of items between stations, the limited ports at the station means a much less transfer rate can be realized in end-to-end transfer using the train.

Construction
Railways can be laid on the ground. It cannot loop upside-down.

Minimum and maximum build length
The length for a single segment is limited to between 12 to 100 meters. You can join multiple segments end to end to build a longer rail.

Cost
The cost of the rail is 1 Steel Pipe + 1 Steel Beam at the first 18 meters, and 1 Steel Pipe + 1 Steel Beam for every 12 subsequent meters. Due to the building length constrains, it is capped at 8 Steel Pipes + 8 Steel Beams.

Turning radius
The minimum radius is 17 meters. To achieve this tight turn you have to build a straight segment, then the curves, then the next straight segment (or curved) in order. If you build 2 straight segments then build the curve last, it will shows 'The Railroad Track has a too sharp turn!' instead.

Building of curved section
The building of railway curve is currently glitchy. If start building from an existing railway and build a curved Railway with a free end, it is usually easier to build. However if attempt to connect 2 existing railways with a curve, it will show 'Turning Radius too tight' warning, despite the radius is larger than 17 meters. Therefore if a curved railway cannot be build, try to rebuild it with a different build order.

Maximum slope
If the starting and ending points lie on the horizontal surface such as foundations, the maximum slope is 28 meters high over the distance of 94.5 meters, which is 1:3.375. If both starting and ending points lie on the Ramp 8m x 2m, the maximum slope can be increased to 1:2.7. You could not build a rail on a Ramp 8m x 4m.

The steepest measured slope is 1:2.322. To achieve this you have to find terrain with matching gradient or by building short segments of sloping rails below the main rail.

Build order
It is advised to build the Train Station before building the rail. Attempt to build the station on top of the existing railway, the station will be built on top of it but not connected. You could, however, build the railway with free end snapped to the foundation then build a train station at the end of it. Same applied to Freight Platforms.

End of line loop
It is advised to put a end-of-line loop for single direction train. Building the loop itself takes trial and error, and separate the loop into several shorter curves are advised: the shorter the curve, the lesser chance that 'Too tight turn!' warning will appear.

Collision width
There is no collision box implemented at the moment, which means that the rail (and entire trains) can clip through the ground. Judging from the visual it is about 6 meters wide and 1 meter high.

Snapping
Rails snap on foundations, ramps, Train Stations, Freight Platforms and Empty Platforms.

Dismantle
You can dismantle the rail at any time. You cannot dismantle the rail in a train station; you have to dismantle the train station instead. Dismantling a rail segment with a train moving on it will stop the train. Dismantling a rail splitway will remove the Railroad Switch Control together.

Supporting columns
There are no supporting columns for the rail, as opposed to what is displayed in the E3 trailer. The latitude curvature of a rail is only dependent on the slope of the starting and ending points, which means if the starting and ending points lie on a flat surface such as foundations, the rail will be perfectly horizontal, despite a large gap in between. On the other hand, attempting to build on uneven ground could lead to unexpected sloping of rail.

Derailing
A train cannot derail when approaching the end of the rail with high speed. Instead, it will simply stop abruptly at the end of the rail. The train segments will be 'compressed' together visually.

Keys to build a straight railway
Sometimes you may wonder a railway looks curvy, even though you have built it on the foundations. It is because the very first segment that you built on the foundation is not straight: and that curvatures passed down to the next segment you build and it never dissipates. Make sure the railway is straight from the beginning.

Splitway
Switches are made by joining two rail segments and then adding a third segment to that junction. A flag will be placed on the switch, but currently, it's wonky, and its setting is ignored by automated trains. A railway split cannot be created directly before or after a Train station or freight platfrom, so a short piece of railway is required in between.

Power
Railways conduct Power to ridden Electric Locomotives and connected Train stations, which can be used as the backbone of a Power Grid. A simple crossroad will not conduct power to the crossing railway; both railways must be connected with a split way or intersection to do so.

Current issue

 * Sometimes when a railway split is built, but a Railroad Switch Control is not created automatically. In that case, the junction will not work, that means a train might get stuck on its route or it simply won't run on its automatic schedule. You need to ensure a Switch Control is created at every railway split. Try to rebuild the railway junction in different order.
 * When automated train passes through a railway junction, some of the wagons will be teleported to the other junction, then merged back to the line. Its functionality is not affected.
 * If a railway split leading to a 2-way train station is built too near the station, sometime it can cause the 2-way train to move into the wrong splitway, causing the train to stuck. To prevent this, have at least 2 railway segments between the splitway and the train station.
 * This issue does not apply to 1-way train or railway with loops.

Trivia

 * Using the fact that rails currently do not have collision hitboxes, it is possible to make a Train line (or any other mode of transportation of Pioneers or Items) go through most solid natural obstacles (mountains, rocks, etc.).