You know that the time difference (tdiff) between the “shock wave” (SW) and the “muzzle blast” (MB) for a supersonic gunshot is dependent on the distance between the shooter and the perpendicular projection of the microphone position on the bullet trajectory and also on the speed of the bullet relative to that of the sound.
If we look at the audio recordings and in particular that of Trump’s microphone we see that tdiff is maximum for shot 1 and lower for the other 7 shots. This has generally been attributed to variations in bullet speed between the different shots. This may be one reason but there is another: if there is a lateral shift in the trajectory compared to that of the first shot there will be a decrease in tdiff if this new trajectory moves away from the microphone and an increase if it gets closer to it.
I used 5 recordings of which 4 showed a decrease in tdiff and 1 an increase. If I assume that the variation in ball speed between the different shots is minimal, the position of the microphones indicates that shots 2 to 8 pass to the east of Trump’s microphone. The importance of the variation in tdiff is proportional to the deviation in the trajectory. By simulation I calculated the theoretical lateral deviation corresponding to the variation in tdiff for the 7 shots and the 5 recordings and for each shot I averaged the deviations over the 5 recordings.
The results are as follows in lateral deviation in meters towards the east at the podium level.
Shot 2: 2.2 m
Shot 3: 3.9 m
Shot 4: 4.1 m
Shot 5: 3.5 m
Shot 6: 4.5 m
Shot 7: 5 m
Shot 8: 1.4 m
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