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.
Simulation with an invented timetable — not real data. Unofficial hobby project, not affiliated with Deutsche Bahn.
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.
"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.
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
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.
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.
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.