At that point in time, the Langley pilots did not know the threat they were facing, did not know where United 93 was located, and did not have shootdown authorization.
( ( At ( ( that point ) ( in time ) ) ) ( , ( ( the ( Langley pilots ) ) ( ( ( ( ( ( ( ( did not ) ( know ( ( the threat ) ( they ( were facing ) ) ) ) ) , ) ( ( did not ) ( know ( where ( ( United 93 ) ( was located ) ) ) ) ) ) , ) and ) ( ( did not ) ( have ( shootdown authorization ) ) ) ) . ) ) ) )
(ROOT (S (PP (IN At) (NP (NP (DT that) (NN point)) (PP (IN in) (NP (NN time))))) (, ,) (NP (DT the) (NNP Langley) (NNS pilots)) (VP (VP (VBD did) (RB not) (VP (VB know) (NP (NP (DT the) (NN threat)) (SBAR (S (NP (PRP they)) (VP (VBD were) (VP (VBG facing)))))))) (, ,) (VP (VBD did) (RB not) (VP (VB know) (SBAR (WHADVP (WRB where)) (S (NP (NNP United) (CD 93)) (VP (VBD was) (VP (VBN located))))))) (, ,) (CC and) (VP (VBD did) (RB not) (VP (VB have) (NP (NN shootdown) (NN authorization))))) (. .)))
In that moment the Langley pilots were unaware of the threat, the location of United 93 and had no authorization to engage.
( ( In ( that moment ) ) ( ( the ( Langley pilots ) ) ( ( ( ( ( were unaware ) ( of ( ( ( the threat ) , ) ( ( the location ) ( of ( United 93 ) ) ) ) ) ) and ) ( had ( no ( authorization ( to engage ) ) ) ) ) . ) ) )
(ROOT (S (PP (IN In) (NP (DT that) (NN moment))) (NP (DT the) (NNP Langley) (NNS pilots)) (VP (VP (VBD were) (ADJP (JJ unaware)) (PP (IN of) (NP (NP (DT the) (NN threat)) (, ,) (NP (NP (DT the) (NN location)) (PP (IN of) (NP (NNP United) (CD 93))))))) (CC and) (VP (VBD had) (NP (DT no) (NN authorization) (S (VP (TO to) (VP (VB engage))))))) (. .)))