(CNN) -- Three times Marilyn Jean Hartman attempted to slip past airport security checkpoints to stowaway on airplanes.
And three times the 62-year-old Hartman got caught.
This week, authorities say she made it through a screening checkpoint at Mineta San Jose International Airport without a ticket and boarded a Southwest Airlines flight bound for Los Angeles International Airport.
"If you Google her name, you will see she had been arrested before but not at our airport," San Jose airport spokeswoman Rosemary Barnes said.
Hartman was arrested Monday at the Los Angeles airport, according to a statement released by airport police.
She pleaded no contest Wednesday to a misdemeanor count of stowing away, CNN affiliate KTLA reported. She was sentenced to two years probation and three days in jail. She was given credit for time served and released.
Outside the courthouse, Hartman refused to detail to reporters how she got through security.
"I don't think it's wise to say how I got through. I don't want to help the enemy," she said.
"...I want to go with a paid ticket. ... I want to do everything legal," Hartman said. "It was clearly wrong on my part. ... It was stupid and it is something I don't want to repeat."
Hartman was arrested Monday night after the flight crew determined she did not have a ticket, police said.
The flight crew conducted a head count and discovered Hartman "was not a ticketed passenger on Southwest Airlines," the police said. It was unclear how the crew determined Hartman stowed away.
"Further investigation revealed there was no confirmed reservation in the system and Hartman had no documents to show proof that she had purchased a ticket," the statement said.
It's the second time San Jose International Airport has made headlines in recent months over a reported stowaway.
In April, 15-year-old Yahya Abdi crawled into the wheel well of a Hawaii-bound 767 and lost consciousness when the plane took off. He was caught after climbing out of the plane and onto the tarmac at Kahului Airport on the island of Maui.
The incident raised questions about how the teen was able to breach security at the airport.
Hartman's actions raised the question again this week.
Hartman apparently blended in with a family at a checkpoint where a Transportation Security Administration agent was checking tickets and identification, CNN affiliate KTVU reported, citing an unnamed source familiar with the case.
She is then accused of doing the same thing -- blending in with a family -- to board the flight, the source said.
San Jose airport officials and the TSA said at no time were passengers in jeopardy.
Hartman "was screened by TSA for any prohibited items. It's really important to point that out," Barnes said. "And public safety was not compromised in any way."
Even so, the TSA is making "minor modifications" to the layout of its passenger screening area to prevent another incident, said Ross Feinstein, the TSA press secretary.
Hartman has been described by authorities as a serial stowaway, who has repeatedly tried to board flights to Hawaii at San Francisco International Airport without a ticket.
Earlier this year, she was sentenced to probation and ordered to stay away from the San Francisco airport.
CNN's Janet DiGiacomo contributed to this report.