04_timeline

Who entered first, and by how much

Each vehicle’s solved speed and pose at contact, walked back up its own approach to the point where its front bumper crossed its stop line. The gap between those two moments is the entry order — reported as an interval, because that is what the evidence supports.

Vehicle B crossed its stop line 1.14 s before vehicle A crossed its own, on a 5th-to-95th percentile interval of 1.02 to 1.27 s. The interval does not include zero, so the entry order is established by the physical evidence at this confidence.
Stop-line crossing
VehicleBefore contactIntervalSpeed thereBasis
A0.30 s0.26–0.33 s52 km/hTelematics shows no material deceleration in the 3 s before impact (0.02 m/s^2); constant speed is used.
B1.43 s1.29–1.59 s40 km/hNo telematics for this vehicle; constant speed is assumed between the stop line and impact, which is the assumption most favourable to a later entry and is stated as such.
Time to impact — vehicle A
MomentTime to impactDistance to impactSpeed
this vehicle's front bumper crossed its own stop line0.30 s4 m52 km/h
the other vehicle crossed its stop line1.43 s21 m52 km/h
line of sight to the other vehicle first clear3.90 s56 m52 km/h

Time to impact is measured backwards along this vehicle's own approach from the solved contact instant. It states how long each driver had, not what either driver did with it.

Time to impact — vehicle B
MomentTime to impactDistance to impactSpeed
this vehicle's front bumper crossed its own stop line1.43 s16 m40 km/h
the other vehicle crossed its stop line0.30 s3 m40 km/h
line of sight to the other vehicle first clear3.90 s43 m40 km/h

Time to impact is measured backwards along this vehicle's own approach from the solved contact instant. It states how long each driver had, not what either driver did with it.

Events

Fused timeline
t from contactVehicleEvent±Source
-3.90 sBvehicle A first visible beyond the corner wall (dashcam)0.07 sclip dashcam-B frame 63
-3.90 sAline of sight to the other vehicle first clear0.10 sscene sight-line analysis at the reconstructed motion
-3.90 sBline of sight to the other vehicle first clear0.10 sscene sight-line analysis at the reconstructed motion
-1.43 sBfront bumper crosses the Church Street (south approach) stop line at 40 km/h0.15 sreconstruction: solved speed walked back 15.8 m up the approach
-0.29 sAfront bumper crosses the Main Road (west approach) stop line at 52 km/h0.04 sreconstruction: solved speed walked back 4.3 m up the approach
+0.00 sA+Bcontact0.00 sreconstruction: impact solution
+0.00 sAtelematics event: HARSH_DECELERATION1.00 sprovider export (Fleet tracking provider (anonymised))
+0.00 sBcontact (dashcam)0.07 sclip dashcam-B frame 180

Corroboration

Sight lines

Signal phase. Signal phase timing was requested from the municipality and was not obtained. Conclusions are framed on entry order and speed, not on light colour. No clip in this bundle shows a signal head, so this reconstruction makes no statement about which vehicle had a green light. It establishes entry order and speed.