(S (S (NP (BASENP (NN Preoccupation)) (PP (IN with) (NP (BASENP (DT a) (NN malfunction)) (PP (IN of) (BASENP (DT the) (NNP Inertial) (NNP Reference) (NNP System)))))) (VP (VP (VP (VBD diverted) (NP (BASENP (DT both) (NN pilot) (POS 's)) (NN attention))) (PP (IN from) (BASENP (DT the) (NN flight) (NNS instruments)))) (CC and) (VP (VBD allowed) (S (NP (DT the) (NP (BASENP (VBG increasing) (NN descent)) (CC and) (BASENP (NN bank) (NN angle)))) (VP (TO to) (VP (VBN unnoticed))))))) (PERIOD ...))