..in a wind tunnel, using hydrogen as fuel. Which is ok on the ground but the problem with hydrogen is the volume density of the fuel and low boiling point. The space shuttles massive tank carried 8 minutes of fuel for its RS-25 engine. The tanks were especially insulated to keep the hydrogen at minus 423 degrees Fahrenheit. How do propose to fuel a hydrogen powered sodramjet engine in an actual Mach 20 flight?
So when you say the sodramjet has flown you are attempting to mislead the gullible - aren't you?
The Mach 20 flight did not disclose what engine if any engine it was using.
I said China has scramjet, TRCC combined cycle, TBCC combined cycle, Sodramjet (which is NASA's name for a theoretical engine) aka oblique detonation wave engine, and a rotating detonation engine. BUT you are right in that the sodramjet at least public information on it say no test flight but lab test. The test flight was for rotating detonation engine rather than the sodramjet. But not saying sodramjet has also been test flown doesn't mean it hasn't but we'll leave that at what is known publicly and revealed about it.
I mistook sodramjet for rotating detonation engine which has been test flown. These are two separate types of engines.
As for the mach 20 flight that was 40,000km ranged or so, that supposedly missed its target by 24 miles (lol). This object apparently released a payload projectile which at first China said was testing space launch system after lots of noise about FOBS. Then Ministry of Foreign Affairs message about only being spacelaunch technology was rebutted eventually by China admitting this can be weaponized and the speculation about the projectile fired from the aircraft was filled with speculation.
It's interesting to note that China reported that it has flown and landed one of the Tengyun project aircrafts which most likely (speculated) to use some combined cycle engines. This would not be a weaponized sodramjet powered or scramjet or any other powered type since it is designed as single stage or two stage to orbit craft and reusable hypersonic inside the atmosphere. This test flight was done in 2021 and it is unknown yet whether this is the exact same craft as the mach 20, 40,000km ranged flight object.
In any case, it seems the less sensitive engines are revealed and reported on. Anything truly militarily sensitive is most likely hidden unless it serves some strategic purpose to reveal hints about. In any case the known have flown type of engines in China is scramjet, TRCC, TBCC (one is kerosene fuel I believe), rotating detonation engine. The lab only is sodramjet. These are the known info. Not reported doesn't mean doesn't exist or not flown though but let's assume it is so.
As for DF-ZF aka DF-17 rocket's vehicle, it is so old and non-sensitive that it is allowed to be sold to North Korea in small numbers. That one is assumed to be a waverider on MRBM booster... but again waveriders have certain attributes that are harder than HCM. Usually higher speeds of flight and extremely difficult control mechanisms and guidance sensor chains. For China the US already knows that includes dozens of satellites spanning at least three constellation series types and HALE drones such as WZ-8. Recently Chinese state media even mentioned that sensor node chains include regular aircraft as potential for acting as targeting nodes and sensor nodes. Every platform communicates and can participate rather than just the satellites and HALEs.
anyway this is now off topic but I wonder whether those two flights are the same aircraft or from the same Tengyun project.
As for HAWC and ARRW. ARRW has tested the booster successfully now. HAWC has tested its scramjet engine successfully now.
Scramjet the US mastered a long time ago. I guess for HCM, it is a matter of keeping the engine lit for the entire duration while performing some tasks and maybe turns as well.