Chinese commercial space enterprise YUNXING completed on Tuesday in northwestern China the test flight for the ramjet of its series of supersonic airliners which is expected to have its maiden flight in 2026. The jet engine coded "JINDOU-400" has the thrust of over 400 kilograms. It achieved four times the speed of sound at an altitude of more than 20 kilometers. According to YUNXING, the performance data in the test flight fully verified the stability and reliability of the engine.