Column Left March Procedures
During a column movement, the base element is the squad on the flank in the direction of the turn.
To change the direction 90 degrees, the command is Column Right (Left), MARCH. On the command of execution MARCH, the base squad executes the movement as in squad drill except that the squad leader takes one 30-inch step and then takes up the Half Step. The squad leader continues marching with the Half Step until the other squad leaders come abreast. The other squad leaders, while maintaining correct (offset) interval, execute a 45- degree pivot and continue marching in an arc. As they come on line (abreast) with the base squad leader, they take up the Half Step. When all squad leaders are abreast, they step off with a 30-inch step without command. All other platoon members march forward on the command of execution and execute the column movement at approximately the same location as their squad leaders and in the same manner.
Video:
http://www.pdf-archive.com/2014/01/22/army-tc-3-21-5/army-tc-3-21-5.pdf
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