But as D.J.I. courts more industrial customers such as utilities and developers, the company’s drones — and the vast quantities of footage taken by their cameras — have come under scrutiny.

United States customs officials said in a memo this year that D.J.I.’s drones were sending sensitive information about American infrastructure back to China. The report, from the Los Angeles office of the Immigration and Customs Enforcement bureau, cited an unnamed source in the drone industry.

D.J.I. — formally named Da Jiang Innovations Science and Technology Company — denied the allegations, saying the memo was “based on clearly false and misleading claims.”

This year, the United States Army also ordered its units to discontinue the use of D.J.I. drones, equipment and software, citing unspecified “cyber vulnerabilities.”

Such concerns have scarcely dampened the public’s enthusiasm for drones in China.

In Wuhan, the Ewatt Aerospace Flight Academy is expanding. The school, which is run by the industrial-drone maker Ewatt, was the first in China to be accredited to issue the license needed to pilot heavy industrial drones. Its one-month course attracts people who hope to work either for a drone maker or for another kind of company that needs drone operators.

“More and more people want to learn,” said the school’s dean, Li Chunfei.