) ▁ ▁Ex erc ise ▁assumed ▁friend ▁( M ) ▁ ▁Ex erc ise ▁friend ▁( D ) ▁ ▁Ex erc ise ▁neutral ▁( L ) ▁ ▁J oker ▁( J ) ▁( ex erc ise ▁suspect ) ▁ ▁F aker ▁( K ) ▁( ex erc ise ▁host ile ) ▁ ▁There ▁are ▁no ▁" ass umed ▁neutral " ▁and ▁" ex erc ise ▁assumed ▁neutral " ▁affili ations . ▁ ▁These ▁colors ▁are ▁used ▁in ▁phr ases ▁such ▁as ▁" blue ▁on ▁blue " ▁for ▁friendly ▁fire , ▁blue ▁force ▁tracking , ▁red ▁team ing , ▁and ▁Red ▁C ells . ▁ ▁AP P - 6 ▁Col our ▁representation ▁The ▁concept ▁of ▁affili ation ▁does ▁not ▁appear ▁in ▁the ▁original ▁AP P - 6 ▁as ▁these ▁were ▁not ▁introduced ▁until ▁AP P - 6 A . ▁Instead , ▁the ▁original ▁AP P - 6 ▁described ▁a ▁series ▁of ▁" col our ▁representations " ▁with ▁the ▁purpose ▁of ▁distingu ishing ▁friendly ▁and ▁enemy ▁elements . ▁ ▁Multi - col our ▁representation : ▁ ▁Blue ▁or ▁black ▁for ▁friendly ▁icons ▁Red ▁for ▁enemy ▁icons ▁Green ▁for ▁man - made ▁obst acles ▁( friend ly ▁or ▁enemy ) ▁Y ellow ▁for ▁chemical , ▁bi ological , ▁radi ological ▁or ▁nuclear ▁events ▁Other ▁colours ▁to ▁be ▁established ▁in ▁a ▁map ▁legend ▁tri - col our ▁representation : ▁ ▁Blue ▁or ▁black ▁for ▁friendly ▁icons ▁Red ▁for ▁enemy ▁icons ▁Green ▁or ▁yellow ▁for ▁man - made ▁obst acles ▁( friend ly ▁or ▁enemy ) ▁and ▁for