all 6 of them!
Each booster generates 3 distinct "booms". IIRC the causes of each are slightly different, but it's nutty hearing it in person!
Each booster generates 3 distinct "booms". IIRC the causes of each are slightly different, but it's nutty hearing it in person!
One is from the engine bell, one from the widest part of the body by the landing legs, and the third is the grid fins.