9 0 4 ▁and ▁ 1 8 ▁December ▁ 1 9 0 5 . ▁ ▁G ago ▁C out inho ▁was ▁nominated ▁head ▁of ▁the ▁Ge odes ical ▁Mission ▁of ▁Eastern ▁Africa ▁in ▁May ▁ 1 9 0 7 , ▁a ▁post ▁he ▁held ▁until ▁the ▁beginning ▁of ▁ 1 9 1 1 . ▁It ▁was ▁during ▁his ▁assignment ▁that ▁he ▁met ▁Portuguese ▁av i ator ▁pione er ▁Art ur ▁de ▁Sac ad ura ▁Cab ral , ▁who ▁become ▁his ▁close ▁friend ▁and ▁who ▁would ▁be ▁his ▁ment or ▁for ▁future ▁av iation ▁projects . ▁After wards , ▁he ▁led ▁the ▁Portuguese ▁mission ▁that ▁del im ited ▁Ang ola ▁borders ▁in ▁Bar ot ze , ▁which ▁was ▁formed ▁in ▁ 1 9 1 2 . ▁The ▁year ▁after ▁his ▁return ▁to ▁Portugal , ▁he ▁was ▁nominated ▁the ▁head ▁of ▁the ▁Ge odes ical ▁Mission ▁of ▁São ▁Tom é ▁and ▁Pr ín cipe , ▁in ▁ 1 9 1 5 , ▁which ▁he ▁was ▁until ▁middle ▁ 1 9 1 9 . ▁In ▁ 1 9 1 7 , ▁G ago ▁C out inho ▁and ▁Art ur ▁de ▁Sac ad ura ▁Cab ral ▁did ▁their ▁first ▁fl ights ▁together . ▁In ▁ 1 9 1 9 , ▁encourag ed ▁by ▁his ▁friend , ▁he ▁started ▁to ▁dedic ate ▁himself ▁to ▁the ▁improvement ▁of ▁the ▁aer ial ▁navigation ▁methods . ▁They ▁took ▁several ▁fl ights ▁together ▁to ▁study ▁the ▁methods , ▁the ▁most ▁important ▁was ▁the ▁first ▁flight ▁from ▁Lis bon ▁to ▁F unch al