At 8:51, the flight deviated from its assigned altitude, and a minute later New York air traffic controllers began repeatedly and unsuccessfully trying to contact it.
( ( At 8:51 ) ( , ( ( ( ( ( ( the flight ) ( deviated ( from ( its ( assigned altitude ) ) ) ) ) , ) and ) ( ( ( a minute ) later ) ( ( New ( York ( air ( traffic controllers ) ) ) ) ( began ( ( repeatedly and ) ( unsuccessfully ( trying ( to ( contact it ) ) ) ) ) ) ) ) ) . ) ) )
(ROOT (S (PP (IN At) (NP (CD 8:51))) (, ,) (S (NP (DT the) (NN flight)) (VP (VBD deviated) (PP (IN from) (NP (PRP$ its) (VBN assigned) (NN altitude))))) (, ,) (CC and) (S (ADVP (NP (DT a) (NN minute)) (RB later)) (NP (NNP New) (NNP York) (NN air) (NN traffic) (NNS controllers)) (VP (VBD began) (UCP (ADVP (RB repeatedly)) (CC and) (VP (ADVP (RB unsuccessfully)) (VBG trying) (S (VP (TO to) (VP (VB contact) (NP (PRP it))))))))) (. .)))
New York traffic controllers tried a hundred times in vain to contact the plane.
( ( New ( York ( traffic controllers ) ) ) ( ( ( ( tried ( a ( hundred times ) ) ) ( in vain ) ) ( to ( contact ( the plane ) ) ) ) . ) )
(ROOT (S (NP (NNP New) (NNP York) (NN traffic) (NNS controllers)) (VP (VBD tried) (NP (QP (DT a) (CD hundred) (NNS times))) (PP (IN in) (NP (JJ vain))) (S (VP (TO to) (VP (VB contact) (NP (DT the) (NN plane)))))) (. .)))