A drug dealer tried to run over a policeman to avoid arrest and drove around 70 metres with the officer on his bonnet.
Sergeant Paul Street said it was "pure luck" that he escaped serious injury, and managed to detain 27-year-old Andre George after the vehicle stopped in Cambridge.
George, of Crome Road, Brent, north-west London, was jailed for more than four years at Peterborough Crown Court on Friday after admitting being concerned with the supply of Class A drugs and assault with intent to resist arrest, Cambridgeshire Police said.
Two plain-clothes police officers had spotted the defendant dealing drugs from a vehicle in Cambridge on November 3 last year.
The officers approached George and identified themselves.
George then drove off, knocking Sergeant Street onto the bonnet and travelling approximately 70 metres with the officer on the vehicle.
Sergeant Street was uninjured and managed to arrest George when the vehicle stopped.
George was sentenced to three years and six months in prison for being concerned with the supply of a Class A drug and seven months for assault with intent to resist arrest, with the sentences to run consecutively.
Detective Constable James Weston, who investigated the incident, said: "It is remarkable that Sergeant Street avoided injury in an incident that could have been a lot worse."
Sergeant Street said: "This was an extremely unpleasant experience which highlights the dangers that police officers face on a day-to-day basis.
"It is hard to explain just how frightening it was being on the bonnet of a vehicle travelling at speed, but it was by pure luck that nobody was seriously injured as a result of this incident.
"I think the sentence reflects the violent nature of this crime."