Dual Tetrathorp-Junction

From OpenTTD

Railway junctions 3-Way junctions Basic 3-Way Line Merge Half Cloverleaf Half Spaghetti Compact 3-Way Compact 3-Way B-M Junction Ultimate 3-way 4-Way junctions Basic 4-Way Roundabout Cloverleaf Spaghetti Star Complex Star Branch-Merge Over-Under Tetrathorp Pre-Signaled Roundabout Advanced Roundabout Right-of-way Roundabout Enormous junctions Double Cloverleaf Dual Tetrathorp Dual Branch-Merge Quad Branch-Merge 8-Way Star Other junctions Right-of-way Depot Dual tunnels Right-of-way Lane Change Unuseful juctions Crossover 3/4ths junction Ultimate 3-way junction for 4 tracks

The Dual Tetrathorp Junction is a Tetrathorp-Junction for double mainlines. It is ideally suited for mainlines at different height levels (in the following referred to as "Diff-Lev-Mains").

Contents 1 Pros 2 Cons 3 Tips 4 Variations 5 Technical Data

[edit] Pros

Putthrough:

• Tracks split before they merge, avoiding deadlocks.
• Can handle many trains at a time, Traffic jams are unlikely.

Speed:

• Turning trains have to go up and down (On "Diff-Lev-Mains": up OR down) a slope only once.
• No Bridges, no sharp bends, allowing 132km/h everywhere.
• On "Diff-Lev-Mains", both mainlines have no slopes.
• Trains don't have to loop around like they do in a double cloverleaf.

Special Features:

• Turning lanes are natural (To turn left you just turn left), making Waypoints unnessesary.
• Turning lanes merge each other first and have a build-in load balancer before they merge the main line, allowing trains to go from inner lanes to outer lanes and vice versa, so that they can pick the new mainline with less traffic.
• Modular design: You can build the inner lanes first, with only little more space than the single Tetrathorp-Junction and add the outer lanes later.

Building:

• Easier to remember and to build than the dual Branch-Merge.

[edit] Cons

Puttrough:

• 10 6-long tunnels and 8 5-long tunnels. (Could be limited to 4-long tunnels by expanding the whole junction 3 tiles on both sides.)

Speed:

• On "Same-Lev-Mains", one pair of mainlines gets slopes, like on other split-before-merge junctions.
• On "Same-Lev-Mains", Trains have to go up and down slopes, like on other split-before-merge junctions.

Special Features:

• Requires the building on slopes patch to be enabled.

Building:

• Needs as much space as the dual Branch-Merge, costs about 330k Pounds.
• Probably harder to remember than the double cloverleaf.

[edit] Tips

• Make the outer lanes for turning right longer, such that they can hold your longest train.
• Start building the inner single Tetrathorp and check if it works.

[edit] Variations

This Dual Tetrathorp junction is optimized for flat terrain.

This is the inner single Terathorp for the original junction and the flat variation. The outer landscaping is for the flat variation.

The load balancers of the above variations can be improved like this. The zigzagging exits keep trains from crossing the whole load balancer if their neighboring mainline is free. Additionally priority is given to the outer right-turning-lane(2) and to the mainlines (1 and 3).

[edit] Technical Data

• 40 free squares
• 38 tunnels

Cost of the flat variation:

• Landscaping: 59.592 Pounds
• Inner Tetrathorp: 134.138 Pounds
• Outer Tetrathorp: 132.462 Pounds
• Total: 326.984 Pounds