BEIJING - As a child, Liu Yang once wanted to be a bus conductor and later had her sights set on becoming a lawyer, but decades later she has travelled into space as China's first ever female astronaut.

It was a visit by the People's Liberation Army (PLA) to her school in central China that changed young Liu's mind as she realised she wanted to become a pilot - a decision that eventually saw her take on the historic role.

Liu, 33, was unveiled as China's first female astronaut on Friday, and blasted off to space on Saturday along with two other male colleagues aboard the Shenzhou-9 spacecraft, in China's most ambitious space mission yet.

"From day one I have been told I am no different from the male astronauts," Liu, a trained pilot who is married but has no children, said in comments carried by state media before the launch.

Liu first joined the army in 1997, and has racked up 1,680 flying hours since then, according to the state-run Xinhua news agency.

She was recruited as a prospective astronaut in May 2010 before being confirmed as one of six candidates shortlisted for the Shenzhou-9 spacecraft mission three months ago.

"As a pilot, I flew in the sky. Now that I am an astronaut, I will fly in space. This flight will be much higher and further away," Liu - a keen cook who likes to make "cola chicken wings" - told reporters ahead of the launch.

China is the third country after the Soviet Union and United States to send a woman into space using its own technology. Liu joined two male colleagues, Jing Haipeng and Liu Wang.

"As much as possible, I would like to experience the weightless environment of space, appreciate the beauty of Earth, to see our beautiful home," she told reporters.

"I will record my own feelings and experiences, and bring them back to share with everyone."

But as a child, Liu did not dream of the stars, and instead wanted to become "a lawyer like the ones in television series," according to Xinhua.

"The first time she sat on a bus with her mother, she also thought becoming a bus conductor would be great, as she could ride the bus every day," it said.

Decades later, she has become a national heroine, and her mission is being excitedly followed in the Chinese media and on the country's popular microblogs.

Banners have reportedly been put up at her former high school in central China's Henan province to celebrate her selection as the country's first female "taikonaut", as the country dubs its space travellers.

State broadcaster CCTV said Liu was selected for her "excellent skills and psychological qualities".

She was once praised for her cool handling of an incident when her jet hit a flock of pigeons, but she was still able to land the heavily damaged aircraft.

Liu is married with no children. State media have said that China requires female astronauts to be married and preferably have a child, due to concerns over potential exposure to radiation that could harm their fertility.

In a CCTV interview, she expressed her gratitude to her husband and said she felt "very guilty" that she had not been able to spend time with her family due to months of training that saw her rehearse for the mission 16 hours a day.

"He has been very supportive of me," Liu said. "I am very thankful to him."

She said she would discuss having children after her return from the mission.

"I love children and life. Being a housewife and spending time with the family is a type of happiness, but being an astronaut perhaps is another type of happiness that not everyone could have," she said, according to Xinhua.