The "Buzz bomb" is a great example, in fact I'm guessing, the only example of a pulse-jet in operation. As I understand, it required an initial velocity so it was launched off a rocket-propelled catapult, then it flew on it's own up to around 400 mph.
Currently there has not been a pulsejet that can start from standstill, since there is no intake velocity, maybe if a fuel/oxygen mix were sprayed and ignited here an air-rocket could propell it to this minimum speed then it could operate until the minimum speed for ramjets, by then it would run like a ramjet by shutting off the pulse sequence.
I don't know why no one has done this yet , maybe I hypothesizing, or it may be an old Black Project.
Hope this helps ya Flywithken
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