Rear March Procedures
This movement is used to change the direction of a marching element 180 degrees in a uniform manner. It is only executed while marching forward with a 30-inch step.
To March to the Rear, the command Rear, MARCH is given as the right foot strikes the marching surface. On the command of execution MARCH, take one more step with the left foot, pivot 180 degrees to the right on the balls of both feet, and step off in the new direction taking a 30-inch step with the trail foot.
Do not allow the arms to swing outward while turning
Video:
http://www.pdf-archive.com/2014/01/22/army-tc-3-21-5/army-tc-3-21-5.pdf
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