Radar data show the Otis fighters were airborne at 8:53.
( ( Radar data ) ( ( show ( ( the ( Otis fighters ) ) ( were ( airborne ( at 8:53 ) ) ) ) ) . ) )
(ROOT (S (NP (NNP Radar) (NNS data)) (VP (VBP show) (SBAR (S (NP (DT the) (NNP Otis) (NNS fighters)) (VP (VBD were) (ADJP (JJ airborne) (PP (IN at) (NP (CD 8:53)))))))) (. .)))
The fighters flew to intercept the hijacked aircraft.
( ( The fighters ) ( ( flew ( to ( intercept ( the ( hijacked aircraft ) ) ) ) ) . ) )
(ROOT (S (NP (DT The) (NNS fighters)) (VP (VBD flew) (S (VP (TO to) (VP (VB intercept) (NP (DT the) (JJ hijacked) (NN aircraft)))))) (. .)))