The first of the Andrews fighters was airborne at 10:38.
( ( ( The first ) ( of ( the ( Andrews fighters ) ) ) ) ( ( was ( airborne ( at 10:38 ) ) ) . ) )
(ROOT (S (NP (NP (DT The) (JJ first)) (PP (IN of) (NP (DT the) (NNP Andrews) (NNS fighters)))) (VP (VBD was) (ADJP (JJ airborne) (PP (IN at) (NP (CD 10:38))))) (. .)))
This left them plenty of time to take out the hijacked aircraft, if only their orders had been clear.
( This ( ( ( ( ( ( left them ) ( plenty ( of time ) ) ) ( to ( ( take out ) ( the ( hijacked aircraft ) ) ) ) ) , ) ( if ( ( only ( their orders ) ) ( had ( been clear ) ) ) ) ) . ) )
(ROOT (S (NP (DT This)) (VP (VBD left) (NP (PRP them)) (PP (ADVP (RB plenty)) (IN of) (NP (NN time))) (S (VP (TO to) (VP (VB take) (PRT (RP out)) (NP (DT the) (JJ hijacked) (NN aircraft))))) (, ,) (SBAR (IN if) (S (NP (RB only) (PRP$ their) (NNS orders)) (VP (VBD had) (VP (VBN been) (ADJP (JJ clear))))))) (. .)))