Thanks for the replies so far. The throttle jammed scenario has happened to me twice, once on a motor-cycle and once with a model aircraft.
For the motor-cycle I had to change into top gear and stand on the rear brake to skid to a halt.
The model aircraft had to be flown on knife-edge until it starved of fuel, then a dead-stick landing. ( it had a transverse fuel tank.)
A few days ago, I just happened to ask London Information if they could tell me my current ground speed. They initially said No.... But two minutes later said that Birmingham Radar had me at 122 knots, which was a pleasant surprise for me.... Thanks Lon Inf.
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