(S (S (PP (VBG According) (PP (TO to) (NP (BASENP (DT the) (NN head)) (PP (IN of) (NP (BASENP (DT the) (JJ technical) (NN commission)) (VP (VBN involved) (PP (IN with) (S (VP (VBG investigating) (BASENP (DT the) (NN crash))))))))))) (COMMA ,) (S (S (NP (BASENP (NNP Alexei) (NNP Morozov)) (COMMA ,) (NP (BASENP (DT the) (NN crew)) (PP (IN of) (BASENP (DT the) (NN aircraft))))) (VP (VBD had) (VP (VBN been) (VP (VBN warned) (PP (IN of) (BASENP (JJ limited) (NN visibility))))))) (COMMA ,) (SBAR (IN although) (S (BASENP (PRP it)) (VP (VP (VBZ has) (RB not)) (VP (VBN been) (VP (VBN determined) (SBAR (SBAR (IN whether) (CC or) (RB not)) (S (NP (NP (BASENP (DT the) (NN crew) (POS 's)) (NN decision)) (S (VP (TO to) (VP (VB land))))) (VP (VBD had) (VP (VBN been) (VP (VBN influenced) (PP (IN by) (NP (BASENP (DT the) (NNS passengers)) (PP (IN on) (BASENP (NN board))))))))))))))))) (PERIOD .))