senk-ju heute ca. 5 Minuten später

Why is my train late? A toy simulation of one busy rail corridor — Köln to Mainz and back along the Rhine — showing how small hiccups grow into big delays when fast, slow and freight trains share the same track, and train sets carry a delay from one trip to the next.

ICE per hour RE per hour Freight per hour Timetable buffer Bad luck Dispatching Cancel trains expected to be late by more than Incident Where From Minutes

Day 1

The line, live

What your app says — and what really happens

The operations centre does not see the trains. It only gets position reports from detection points, a little later, and what the dispatcher types in. From that it forecasts the delay at the next stops, and your app shows the forecast another minute later.

Position reports Forecast Dispatcher enters incident after First guess of its length

Off by, 30 min before arrival

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average gap between the app and the real arrival

App too hopeful by 5+ min

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share of arrivals, 30 min before

Right only … before arrival

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for arrivals 10+ min late: the app was within 3 min of the truth from then on

arriving at

Departures at

"App" is what your phone shows now. The station display rounds up to 5 minutes — "heute ca. 5 Minuten später". The last column is the spoiler: what will really happen. Play the map above and watch the board.

What it means for passengers

DB counts trains at stops. Passengers count minutes at the place they are going — and a train 8 minutes late can cost an hour if the connection is gone. Connections here: RE to Trier at Koblenz (hourly), RB to Bad Kreuznach at Bingen (hourly), S-Bahn to Frankfurt (every 15 min) and RE to Mannheim (hourly) at Mainz. Passenger numbers are invented.

Connecting trains wait up to

Passengers on time

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Average delay per passenger

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Missed connections

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Lost to waiting trains

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passenger-hours of people already on a connecting train that waited

How long should a connecting train wait? (this day)

Waiting saves the people changing trains but delays everyone already on board. Somewhere in between is the least total loss.

How late, counted two ways

Connections

Punctual stops

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passenger arrivals less than 6 min late (DB definition; cancelled stops are left out)

Average delay at the end

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passenger trains

Initial hiccups

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per passenger train: late start, long stops, slow running

Extra waiting at red signals

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all trains, beyond what the timetable planned

Trains today

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Four ways to count the same day

The official figure leaves cancelled stops out. Cancel a train that would be 40 minutes late and the statistic gets better — its passengers do not. Try the "Cancel trains" setting above, ideally with an incident.

Official

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stops less than 6 min late; cancelled stops left out

Cancelled

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of planned stops

Cancelled counted as late

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same, but a cancelled stop is not "on time"

Passengers on time

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at their final destination, including connections and replacement trains

On time, counted three ways

Average delay per passenger

Table view

Every train of the day

Time runs left to right, distance top to bottom. Each line is one train — southbound lines run down, northbound lines up; steeper is slower, flat is standing. The thin grey line behind is the timetable. Hover a train for details, click to set the map's clock.

Show from

When does it tip over?

Same settings, but freight per hour goes from 0 to 12. Each point is the average of 20 random days. Watch how slowly things get worse — until suddenly they don't.

Punctual stops

Minutes per passenger train

Table view

All trains of this day (table)