I'm suprised the larger mirrors would only provice a 3 mile range.
BTW, I think the velocity of sound in air is c 340m/s, which is much slower than a mile /sec (more like 4.5 seconds/mile). In fact it's so slow you can see a wavefront advance: if you watch the video of Queen at Live Aid during "We will rock you" , the audience is clapping in time to the beat, and you can see the "wave" advance from the stage!
John
BTW, I think the velocity of sound in air is c 340m/s, which is much slower than a mile /sec (more like 4.5 seconds/mile). In fact it's so slow you can see a wavefront advance: if you watch the video of Queen at Live Aid during "We will rock you" , the audience is clapping in time to the beat, and you can see the "wave" advance from the stage!
John
Radio Museum collection: Here
