▁the ▁United ▁States ▁In ▁ 1 9 6 6 , ▁James on ▁joined ▁the ▁Aer od ynam ics ▁Section ▁of ▁Gr um man ▁A ircraft ▁Engineering ▁Corporation ▁in ▁Beth page , ▁New ▁York . ▁In ▁this ▁period , ▁his ▁work ▁was ▁largely ▁directed ▁toward ▁the ▁application ▁of ▁automatic ▁control ▁theory ▁to ▁stability ▁augment ation ▁systems . ▁Starting ▁in ▁ 1 9 7 0 , ▁he ▁began ▁to ▁concent rate ▁on ▁the ▁problem ▁of ▁predict ing ▁trans onic ▁flow . ▁Ex isting ▁numerical ▁methods ▁were ▁not ▁equal ▁to ▁the ▁task , ▁and ▁it ▁was ▁clear ▁that ▁new ▁methods ▁would ▁have ▁to ▁be ▁developed . ▁At ▁that ▁time ▁limitations ▁in ▁computer ▁capabilities ▁also ▁pre cluded ▁any ▁attempt ▁to ▁calculate ▁the ▁flow ▁past ▁a ▁complete ▁aircraft , ▁but ▁useful ▁efforts ▁could ▁be ▁made ▁for ▁simpler ▁configurations ▁such ▁as ▁air fo ils ▁and ▁wings . ▁ ▁In ▁ 1 9 7 2 ▁James on ▁moved ▁to ▁the ▁Cour ant ▁Institute ▁of ▁Mathemat ical ▁Sciences ▁at ▁New ▁York ▁University , ▁where ▁he ▁continued ▁his ▁work ▁on ▁trans onic ▁flow . ▁In ▁ 1 9 7 4 ▁he ▁was ▁appointed ▁Professor ▁of ▁Computer ▁Science ▁at ▁New ▁York ▁University . ▁He ▁joined ▁Pr inc eton ▁University ▁in ▁ 1 9 8 0 , ▁and ▁in ▁ 1 9 8 2 ▁he ▁was ▁appointed ▁James ▁Smith ▁Mc D onn ell ▁Dist ingu ished ▁University ▁Professor ▁of ▁A eros pace ▁Engineering . ▁He ▁was ▁Director ▁of ▁the ▁University ' s ▁Program ▁in ▁App lied ▁and ▁Comput ational ▁Mathemat ics ▁from ▁ 1