The stunt
An old steel bridge, a mile of it, closed to cars for decades, with a 22-degree bend in the middle of the river. One run, at night, lit end to end, timed through the bend.
The work
Walking the deck to map every seam. Daylight runs at half speed. Learning the bend until the line through it is the same every time.
The night
Lights down the whole span and the crowd at the finish. The speed through the bend goes on the screen as it happens.
Solve the Jump
How far do you have to lean to hold a turn at speed?
In a turn, the tire has to push you toward the inside. Lean angle depends on speed and how tight the turn is. Go faster or turn tighter and you lean more, until the tire runs out of grip.
Worked example: 30 mph around a 50-meter radius is a 20° lean. Students measure the real bend from a map, then find the fastest speed the tire's grip allows.
The physicstan(lean angle) = speed² ÷ (turn radius × g)
What gets measured
- Speed entering, in and leaving the bend
- Lean angle from the wheel's sensors
- Time over the full mile
What has to be true first
- A night-time closure and permit for the bridge
- The deck inspected seam by seam
- Lighting good enough to read the surface at speed