A FORMER RAF engineer lashed out during a late-night dispute with another man in a city centre taxi queue.

Durham Crown Court heard that the 28-year-old victim was knocked unconscious, after falling backwards with the force of the blow, striking his head on the pavement.

His assailant, David Humphrey, walked off but was seen by passer-by Nicholas Massey, who pinpointed him when police reached the scene.

Caroline Goodwin, prosecuting, said Humphrey, who appeared to be drunk, accepted he was involved in the disturbance and punched the other man, but said he did so because the victim was, "posturing and threatening".

Witnesses said the incident appeared to have been sparked by a "verbal interchange" between the pair, which led to the single punch being thrown by Humphrey.

Miss Goodwin said the victim was taken to hospital suffering a suspected hairline skull fracture, but it proved not to be the case.

He did, however, suffer reddening of the eye and a lump on the eye socket, but there was no resulting deterioration of his sight.

Humphrey, 40, was charged with maliciously inflicting grievous bodily harm.

He denied the offence, but admitted assault causing actual bodily harm, which the prosecution agreed to accept, given that there was no fracture.

James Adkin, for Humphrey, said his client, who is in full-time work with the tea manufacturer Twinnings, had no recent convictions.

But the court heard he had assaults on his record dating back to the early 1990s when he was a ground crew RAF engineer.

Mr Adkin said Humphrey, of George Street, Hetton-le-Hole, maintained that he acted in self-defence, but he accepted that he went too far in striking the man, who he said had verbally abused him and his partner.

Judge Maurice Carr said: "It's clear you have a powerful punch and it was delivered with such force that it knocked the injured party to the ground."

But he said he could avoid imposing a prison sentence because the injury was not as severe as first appeared.

He fined Humphrey £100, and ordered him to pay £250 costs and £500 compensation to the victim.

Judge Carr also awarded £50 from public funds to Mr Massey, a visitor to Durham from Derby, for his "public-spirited" actions.