From an air traffic controller's perspective, that meant maintaining a safe distance between airborne aircraft.
( ( From ( ( an ( air ( traffic ( controller 's ) ) ) ) perspective ) ) ( , ( that ( ( meant ( maintaining ( ( a ( safe distance ) ) ( between ( airborne aircraft ) ) ) ) ) . ) ) ) )
(ROOT (S (PP (IN From) (NP (NP (DT an) (NN air) (NN traffic) (NN controller) (POS 's)) (NN perspective))) (, ,) (NP (DT that)) (VP (VBD meant) (S (VP (VBG maintaining) (NP (NP (DT a) (JJ safe) (NN distance)) (PP (IN between) (NP (JJ airborne) (NN aircraft))))))) (. .)))
There aren't too many airborne accidents due to distance.
( There ( ( ( are n't ) ( ( ( too many ) ( airborne accidents ) ) ( due ( to distance ) ) ) ) . ) )
(ROOT (S (NP (EX There)) (VP (VBP are) (RB n't) (VP (NP (ADJP (RB too) (JJ many)) (JJ airborne) (NNS accidents)) (ADJP (JJ due) (S (VP (TO to) (VP (VB distance))))))) (. .)))