'Aluminum Valley'

The hall's literature tells of how one former hump pilot always referred to the airlift as "Aluminum Valley", because on clear days the crews could see the glistening wreckage of crashed aircraft scattered in the valleys below.

Luo said 990 newly identified martyrs - 586 Chinese and 404 US nationals - will have their names and stories engraved in the hall by August 15. The number of heroes will rise to 4,295, with US nationals accounting for more than 60 percent of the total.

Li Juan, director of the Nanjing Aviators' Association, said the process of finding and identifying the fallen is often difficult and time-consuming. "We have to check the information with known materials, foreign embassies and authorities, including defense departments," he said.

"The association will continue to work with aviation organizations and museums in Taiwan, HongKong, the US and Russia to identify more martyrs.

All the relevant information, including name, rank or title, hometown, dates of birth and death, military experience and cause of death will be recorded. Some relatives have asked for more details so they can learn more about their family's lost heroes.

"We pay our respects to the heroes by identifying them, engraving their names in marble and reuniting them with their old comrades, the men they fought side by side with."

Luo, the hall's deputy director, said researching personal histories and the conflict proved difficult because many of the men were very young when they died.

"The average age of the heroes who were killed was 23," Luo said. "Some of them have been forgotten by posterity and aren't remembered at all. Also, very few experts in China conduct research into the history of Chinese aviation, while the number of experts researching the country's history during World War II is small."

"We'll continue to keep history in mind, commemorate the martyrs, and cherish our life today," he said.

For Sun, the Hump pilots and aircrews are the forgotten heroes of China's WWII history. "The people who flew the airlift may not be as famous and glamorous as the Flying Tigers, but they transported every single gallon of fuel and every bullet used on the battlefield," she said.

"The history of the Hump Airlift was written in the blood of these young heroes. We will always remember their names and hold them close in our hearts."