The former Westlife star was questioned by Australian Federal Police when he and pal Kyle Sandilands left the V Australia flight, after the crew radioed ahead before landing.
It is claimed that McFadden was drunk in business class and had become abusive to passengers and crew, then had to be restrained by Sandilands when he tried to light a cigarette.
However, the singer told a Channel 7 news crew: “I’m an Irishman, I drink a lot of drink. All the time for a long time. It would take a lot more than a couple of vodkas to get me drunk on a plane.
“Someone on the plane had heard me saying I had been smoking in the bathroom and they took from that that I had been.”
Explaining what happened, he added: “We got off the plane and the federal police were there. They said, ‘Have you been smoking on the plane?’ I 100 per cent did not smoke on the plane.'
“I was asleep for most of the flight and then got off. I had a couple of drinks, I’m not going to lie about that. I definitely wasn’t causing a scene or making any problems for anybody.'