Boston Center asked the Herndon Command Center to issue a similar cockpit security alert nationwide.
( ( Boston Center ) ( ( asked ( ( the ( Herndon ( Command Center ) ) ) ( to ( ( issue ( a ( similar ( cockpit ( security alert ) ) ) ) ) nationwide ) ) ) ) . ) )
(ROOT (S (NP (NNP Boston) (NNP Center)) (VP (VBD asked) (S (NP (DT the) (NNP Herndon) (NNP Command) (NNP Center)) (VP (TO to) (VP (VB issue) (NP (DT a) (JJ similar) (NN cockpit) (NN security) (NN alert)) (ADVP (RB nationwide)))))) (. .)))
Boston Center did not issue any requests to send out security alerts.
( ( Boston Center ) ( ( ( did not ) ( issue ( ( any requests ) ( to ( ( send out ) ( security alerts ) ) ) ) ) ) . ) )
(ROOT (S (NP (NNP Boston) (NNP Center)) (VP (VBD did) (RB not) (VP (VB issue) (S (NP (DT any) (NNS requests)) (VP (TO to) (VP (VB send) (PRT (RP out)) (NP (NN security) (NNS alerts))))))) (. .)))