Shootdown authority was first communicated to NEADS at 10:31.
( ( Shootdown authority ) ( ( ( was first ) ( communicated ( to ( NEADS ( at 10:31 ) ) ) ) ) . ) )
(ROOT (S (NP (NN Shootdown) (NN authority)) (VP (VBD was) (ADVP (RB first)) (VP (VBN communicated) (PP (TO to) (NP (NP (NNS NEADS)) (PP (IN at) (NP (CD 10:31))))))) (. .)))
NEADS was given shootdown authority at 9:45.
( NEADS ( ( was ( ( given ( shootdown authority ) ) ( at 9:45 ) ) ) . ) )
(ROOT (S (NP (NNS NEADS)) (VP (VBD was) (VP (VBN given) (NP (NN shootdown) (NN authority)) (PP (IN at) (NP (CD 9:45))))) (. .)))