China 120 First Aid: Why is there no helicopter? Is it a political issue or a financial issue?

At present, parking spaces for helicopters are usually reserved on the roofs of newly-built large hospitals. At present, HEMS is still in a blank in China. The relatively mature operation is Beijing 999. Some hospitals buy one or two helicopters to carry out air ambulance in some areas, while Shandong 999 air ambulance specializes in highway traffic accident rescue.