The CAA punished him with a $2000 fine and gave a formal warning to two staff who were travelling with him.
Mr Brownlee, who was the Transport Minister at the time, said the CAA's punishment was "appropriate for someone in these circumstances".
Mr Brownlee understood that the staff member who allowed him to bypass security still worked at the airport, and again apologised "for putting him in a difficult position".
Mr Brownlee said the staff member was likely to have known who he was, but he did not attempt to use his ministerial influence to get past security.
"I was just not thinking, to be honest."
He understood how his actions could be perceived as arrogant, and said he did not "go around the place looking for some kind of preferment because of a role that I'm very fortunate and privileged to have".
The minister confirmed that he had a lawyer present during questioning by the CAA, because of the potential for court proceedings.
Mr Brownlee said the incident was "deeply embarrassing" and he had learnt his lesson.
"I like queuing now," he said, before adding: "Sorry, I shouldn't make a joke about it, it's not funny."
Labour called for the full report to be released but Mr Brownlee said said that was up to the CAA.
The Civil Aviation Authority launched an inquiry following an incident at Christchurch Airport before the election, when the then Transport Minister and two of his staff deliberately bypassed airport security in order to catch a flight.
Civil Aviation Authority director Graeme Harris said today: "The subjects of this investigation are now fully aware of the importance of abiding by airport security rules, and the consequences of breaching these.
"The publicity surrounding the incident should also act as a warning to the travelling public that any airport security breaches are taken very seriously by the CAA."
Airport security was a "serious matter", he said, and a thorough investigation had taken place in which Mr Brownlee, his staff and witnesses "all co-operated fully".
The investigation was launched following an incident in July, in which Mr Brownlee deliberately bypassed security at Christchurch Airport in order to catch a flight.
The CAA said Mr Brownlee and two parliamentary aides entered a gate lounge through an exit only door.
The parliamentary aides were given formal warnings.
Mr Brownlee was Transport Minister at the time.
He apologised and offered to resign, saying: "Running late for a plane this morning, I took a door that is normally used for an exit at Christchurch airport onto the forecourt ... and you're supposed to go through airport security."
"I didn't initially consider that it was a huge problem. [Only after a phone call from Aviation Security] I suddenly realised, 'Hell, this is a pretty serious matter'.
"I should have known. There's no question, that's why I've offered the resignation."
However, at the time Prime Minister John Key said while he was "really disappointed" in Mr Brownlee, he did not think it was necessary for him to resign, backing the "tremendous things" he'd done during his time as a minister.
Today Mr Brownlee said he was disappointed with himself and had already paid the fine.
"I remain disappointed with myself for the events which occurred at Christchurch Airport on July 24.
"Recognising the importance of security matters I co-operated fully with the Civil Aviation Authority, who conducted a fair and thorough enquiry.
"I've learned from this experience and have paid the fine imposed."
Mr Brownlee is now Minister of Defence, and minister in charge of the Christchurch rebuild.
