Wu Xiaobo, Deputy Director of Thoracic Surgery at a hospital in Wuxi, Jiangsu Province, who assisted with two in-flight medical emergencies while travelling recently too and from the United States. [Screenshot: CCTV]

A Chinese doctor on board a United Airlines flight is being hailed as a hero after saving the life of a passenger who possibly suffered a stroke mid-flight, reports the Beijing Youth Daily.

Wu Xiaobo, Deputy Director of the Thoracic Surgery Department at a hospital in the city of Wuxi, Jiangsu Province was flying to Los Angeles on September 29, 2017, when a fellow passenger fell unconscious and began vomiting.

Responding to an in-flight announcement for a doctor, Wu Xiaobo heeded the call, determining the man in his 50s likely suffered a stroke.

"Cerebral infarction patients may suffer another stroke, and possibly die, if they don't receive timely treatment," said Wu.

He recommended an emergency landing, and two hours later, helped escort the stricken passenger off the flight in San Francisco.

And this wasn't the last time the doctor was called upon to help out a fellow air traveler.

Heading back to China on the same trip, Wu Xiaobo helped assist a female passenger who passed out on his China Eastern flight on October 10.

The young lady fainted, but managed to regain consciousness with the help of the doctor.

Asked about the incidents, a humble Wu Xiaobo is being quoted by the Beijing Youth Daily as saying simply that it's "what a doctor is supposed to do."