▁that ▁they ▁are ▁on ▁the ▁way ▁to ▁having ▁inter cont inental ▁ball istic ▁miss ile ▁( IC B M ) ▁capabilities ▁... " ▁As ▁a ▁weapon , ▁the ▁Se j il - 1 ▁presents ▁much ▁more ▁challenge ▁to ▁Iran ' s ▁potential ▁enemies , ▁as ▁solid - f uel ▁miss iles ▁can ▁be ▁launched ▁with ▁much ▁less ▁notice ▁than ▁liquid - f ue led ▁miss iles , ▁making ▁them ▁more ▁difficult ▁to ▁strike ▁prior ▁to ▁launch . ▁ ▁Se j il - 2 ▁is ▁an ▁upgrad ed ▁version ▁of ▁the ▁Se j il . ▁The ▁Se j il - 2 ▁two - stage ▁solid - f uel ▁miss ile ▁has ▁a ▁ 2 , 0 0 0   km ▁range ▁and ▁was ▁first ▁test ▁fired ▁on ▁ 2 0 ▁May ▁ 2 0 0 9 . ▁The ▁Se j il - 2 ▁surface - to - sur face ▁medium - range ▁ball istic ▁miss ile ▁( MR B M ) ▁was ▁first ▁tested ▁eight ▁months ▁prior ▁to ▁the ▁actual ▁test ▁launch , ▁which ▁took ▁place ▁in ▁the ▁central ▁Iran ian ▁province ▁of ▁Sem nan . ▁Im prov ements ▁include ▁better ▁navigation ▁system , ▁better ▁target ing ▁system , ▁more ▁payload , ▁longer ▁range , ▁faster ▁lift - off , ▁longer ▁storage ▁time , ▁quick er ▁launch , ▁and ▁lower ▁detection ▁possibility . ▁ ▁A ircraft ▁ ▁Any ▁aircraft ▁could ▁potentially ▁be ▁used ▁to ▁host ▁some ▁form ▁of ▁W MD ▁distribution ▁system . ▁Iran ▁has ▁a ▁varied ▁air ▁force ▁with ▁aircraft ▁purchased ▁from ▁many