'I was acting for everyone around me': Captain Hannah Winterbourne comes out as highest-ranking British trans soldier

The British army's highest-ranking openly transgender soldier says her fight to become a woman was harder than anything she saw in combat.

Captain Hannah Winterbourne, 27, said a tour in Afghanistan paled in comparison to the conflict she faced of personal identity – something she's proudly conquered now, The Sun reports.

"I was acting for everyone around me. There was no let up where I could stop that act," she told the London tabloid on Monday.

Now more than a year past her transformation procedure, Captain Winterbourne is leading a company of 100 soldiers, getting support from the British army and going public with her story.

"It's about finding the courage to do it," she said. "And that's not the easiest thing in the world."

Captain Winterbourne realised she wasn't a man at 23 but said fear of hurting her military career kept her from coming out.

At first she came out to doctor at a German post, then a friend back home, and finally, after finishing a six-week tour at Camp Bastion in Afghanistan, she began living openly as a woman. Hormone therapy and surgery completed the change.

She now serves as a captain in the Royal Electrical Mechanical Engineers, where she oversees 100 others and acts as an advisor on transgender issues.

Captain Winterbourne joins Australian transgender military official Catherine McGregor, who was appointed a Member of the Order of Australia in the Military Division for "exceptional service to the Australian Army as the director of the Land Warfare Studies Centre" in 2012.

As of November 2013 she was the highest ranking transgender individual in the Australian Army and the speechwriter and strategic adviser for army chief Lieutenant General David Morrison AO, who refused to accept her resignation when she went public.

She transferred to the Royal Australian Air Force (RAAF) on June 20 to work on projects for the Air Force chief.