Bridge replay

Two runs, one clock: when did the bridge know?

Put two synthetic runs side by side and play them on one mission clock. Each panel shows where the vessel really was against where the receiver said it was, the engine's trust score and band over time, the satellites the log itself lists (the sky blanks where the log hears none), and a verdict when the run ends. Everything drawn comes from a log or from the engine's result for it; nothing is read from the network.

Training and testing only. The runs are synthetic, with invented positions and dates; the coast under them is real land drawn for orientation only, not a chart. A replay shows what was injected and when, so use it at the debrief, not during an exercise. Advisory software. Kshana is not type-approved navigation equipment (IEC 61108, IEC 61162) and says nothing about how any receiver or system would perform against real interference. The operator remains responsible for the navigation of the vessel.

Speed × T+0 s

True track Coast Widen to the coast Show verdicts early

Opening the two demo runs…

What this page does and does not show

The runs are synthetic text made by the engine (kshana nmea-scenario and the Maritime trust demo log). The score and band are the engine's receiver-trust output for each stream, MODELLED: the thresholds are stated in the engine's score model, and no external oracle has checked them against a real receiver.
The skyplot is the log's own GSV: a filled marker is a satellite with a signal strength, a hollow one is listed with none, and a shaded sector is an azimuth range where the log lists satellites and hears none of them. A blocked sky and a jammed signal look the same here. It is not a skyline, and the constellation is nominal, not an ephemeris for the log's date.
"Position error" is the logged distance between the true and the reported position; the ring around the vessel is that distance drawn to scale. The time from an event's onset to the first score below nominal is a subtraction of two logged times, not a detection-performance figure.
The vessel glyph points along the gyro heading (HDT), which no event touches; the dashed outline is where the receiver puts the vessel, along the course it reports. A gap between the two is a debrief cue.
The coast is Natural Earth public-domain land at 1:10 million, bundled with this page (nothing is fetched). The demos' positions are invented, so the coast shows where those invented coordinates fall. Illustration only, never for navigation.