Neil Prendeville wept on air as he apologised for allegedly exposing himself on a flight home from London.
Prendeville broke down on his morning show after a female passenger complained he had opened his trousers in front of her and two air hostesses.
The broadcaster said he had suffered a blackout and blamed a combination of drink and painkillers for his actions and memory loss.
The 49-year-old was an invited guest at Bentley's Oyster Bar and Grill in Piccadilly, owned by chef Richard Corrigan, to promote Cork for business tourists.
"I'd like to take this opportunity to offer my deepest apologies to the passengers on the plane, to the flight personnel, to my family, to my employers, to my work colleagues and to all of the people of Cork and I apologise unreservedly to all concerned," he said on air.
It is understood a passenger alleged the broadcaster, who presents the morning show on Cork's 96fm, tried to perform a sex act as the 10.15pm Aer Lingus flight taxied on the runway at Heathrow on October 19.
Prendeville, who has 100,000 listeners on Ireland's most popular local radio show, said he could not deny that the incident happened because he could not remember.
He had been at the restaurant for just two hours between about 6.30pm and 8.30pm on the night.
Prendeville told listeners: "I'm hoping others and people listening and those writing the article and whatever is to come will learn from this terrible personal experience and not mix painkillers or any tablets with alcohol.
"I have asked and requested that I be given a bit of breathing space and I want to thank my employers and work colleagues for assisting me in this regard and I also want to thank those people who have already shown me the support that I need in this difficult time in my life.
"I don't really have any more to say but I just wish to say and finish that anyone who knows me will hopefully confirm that what is contained in this story is totally out of character. Again my sincere apologies."
Prendeville has been taking pain killers for a continuous neck problem.
A spokeswoman for Aer Lingus said the airline does not comment on security related matters. Cork's 96fm also declined to comment.
Organisers of the event, the Cork Convention Bureau (CCB), said 16 people were invited to London to meet 30 UK conference buyers at an Irish themed dinner in Bentley's. Four journalists were also invited to help promote the links.
Some guests were flown out by the CCB, including Prendeville, who left Cork at 4.15pm and flew out from London on the 10.15pm flight that night.