It was only when police arrived that the dog was finally hauled away from his terrified owner.
Mr McKinley was rushed to hospital where he had an operation on his arm, and is now facing a further three where doctors will try to partially reconstruct his ear.
He said: "I was on the bed stroking him and suddenly he just went. It was just like turning a light switch."
Tyson sunk his teeth into Mr McKinley's left ear and right arm as he attempted to push the pet away.
"He just came back for more," he said. "He was not giving in.
Ms Noble added: "Me and the police were trying to get the dog out of the bedroom and he went for me. It's put me off having another dog for life."
The couple were taken to nearby Pinderfields Hospital in Wakefield, while their dog was taken to kennels.
Mr McKinley has lost 50per cent of his hearing in his left ear but was told it could improve over the next five years.
As well as three reconstructive operations, he will also undergo physiotherapy to help return movement to his right wrist.
He said he has opted to have Tyson humanely put down.
"They said some people, believe it or not, want to keep the dog," he said.
"But I said he should be destroyed.
"It was hard but I couldn't have had him back. I'm just glad it was me and not a kid.
"The police said a kid wouldn't have survived these injuries."
The couple got Tyson when he was around 18 months old.
Mr McKinley said his temperament had always been very good, but that the pet had fought with another dog a few weeks earlier.
He said Tyson had later been found to have distemper, a viral disease, which he believed had made it act aggressively.
Tyson had not been given the recommended vaccinations for parvo or distemper.
Mr McKinley added: "I'd like other people to know that if they're going to buy a dog, particularly a Staffy, they should make sure they don't make the mistake I made.
"I should have asked for a breed certificate and vaccination records, but I took it on trust."
- Daily Mail