can American passport holder get visa on arrival in yinchuan

Hello I am an American Passport holder, i want to fly to Yinchuan just for site seeing for about 3 days, flying from singapore. Can i fly with my roundtrip ticket back to singapore, or do i need to buy another ticket to another destination in order to be able to apply for the VOA. ( As of right now i have no visiting visa stamp in my passport from china) can i fly and get the VOA after i land i yinchuan, Hedong Airport?

Thank you