Some useful details have been revealed in the trial of Metronella McNorgan whose high-speed vehicle killed an eight-year-old pedestrian on November 30, 2021 in London Ontario. News media have reported partial results from a Crash Data Retrieval (CDR) report submitted by the crown alleging McNorgan unintentionally stepped on the accelerator pedal while mistaking it for the brake pedal. This caused her Honda CRV to reach a speed of 121 km/h along Riverside Drive in London.
News media reported that Constable Bradly Yeo was the analyst who conducted the assessment of the data contained in the CDR report. He indicated that the accelerator pedal had been pushed 99 per cent of the way to the floor in the five seconds before the Honda Struck a lamp standard which triggered the recording.
Interestingly it was reported that stability control features in the vehicle activated two seconds before the vehicle struck the lamp standard and this slowed it to 103 km/h. If the Honda was only travelling 103 km/h when it struck the lamp standard then the reported 121 km/h speed must have occurred sometime before, and presumably before the so-called stability control features took effect. If there was only 5-seconds of pre-crash recording then the seconds 5 to 3 seconds before impact were the ones in which the Honda was travelling at 121 km/h, and then the speed was reduced to 103 km/h in the remaining 2 seconds, without the aid of any braking. But this speed reduction would have to occur when the accelerator pedal was pushed 99 per cent of the way to the floor. If braking was not applied then the only way that the Honda reduced its speed is by the stability control system taking over and over-riding the accelerator pedal application. When stability control is activated its purpose is to prevent a vehicle from rotating sideways and this is achieved by applying varying levels of braking to certain wheels so the vehicle points in the direction its travelling. That is an important observation.
During the 2 seconds leading up to the impact with the lamp standard the Honda’s speed was being reduced by about 10 km/h every second and this translates to a rate of deceleration of about .28g. As a comparison, drivers approaching a stop sign typically brake at a rate of .25g. And maximum braking can achieve a deceleration of .7g or higher.
So, to summarize, the police believe that, even though the accelerator pedal was pushed fully to the floor, the stability control system took control and, rather than allowing an acceleration, its caused the Honda to slow down from 121 to 103 km/h before the impact with the lamp standard. Unfortunately news media have not divulged the full contents of the CDR report so it is difficult to conclude whether the conclusions reported by the crown are correct.
It is expected that the defense will call their own expert witness and further conclusions may be made about the CDR data.
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