<p>The team have their own position within each formation, and they all follow the leader.  Red 6 has the easiest job, as he flies mainly in line astern (directly behind the leader).  The situation is a little more complicated for Reds 4, 5, 7, 8 and 9, who each have other aircraft between them and Red 1. 
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In this case, the principle that applies is that they line themselves up on the leader to maintain the correct position, but in a slightly different way. They take one reference from the aircraft closest to them and draw another line (or reference) by lining up the leader's head with the head of the pilot in the aircraft which is next to them.
<a rel="nofollow" class="external text" href="https://www.flickr.com/people/48215073@N00">Santosh Puthran</a>
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<a rel="nofollow" class="external text" href="https://www.flickr.com/photos/talk2santosh/9659055281/">Red Arrows Bournemouth Airshow 2013</a>