. >> whitaker: what was the mission in the gaza valley that day? >> anderson: so, our job, in conjunction with our afghan partners, were to help the afghans in going clearing the gaza valley from any taliban that may be hiding and waiting for the elections to come forth and attack the polling sites. >> whitaker: to help understand what happened that night almost five years ago, using satellite photographs of afghanistan's gaza valley, "60 minutes" commissioned a scale model of the exact location where the friendly fire took place, and brought these three soldiers who fought there to see it. >> anderson: it's surreal to see the whole landscape again, and-- i mean, it definitely-- it definitely brings up memories of that day. >> whitaker: what's the terrain like? >> branch: it's steep and-- and slippery. >> whitaker: hours before dawn, on june 9, 2014, giant chinook helicopters, like these, dropped captain anderson and his 95-man task force of u.s. and afghan soldiers into the gaza valley to chase away the taliban fighters. temperatures soared over 1