Korean Siren in youtube

[Robert Gift]

I can understand it making some sound without the blower operating.

But does it not require supercharged air?

On ***(I've been asked not to use this word before so there is now an automatic replacement censor)*** I believe I heard a Thunderbolt's air quit at the end of a test and the chopper could be barely heard spinning down.

I had expected to hear air being drawn into the SD-10.
I'd expect it standing at the base of a 2t22.

Had I not been holding the camcorder, therefore unable to close my ears,
I would have gone to the pole of the SD-10 to listen.
I wanted to hear how loud it was at the base of it's pole.

I am surprised how much sound emits from the rotor intake of our flashlight siren.