▁At ▁around ▁ 2 0 : 2 9 , ▁while ▁clim bing ▁toward ▁its ▁assigned ▁flight ▁level ▁F L 1 9 0 ▁( 1 9 , 0 0 0   ft ), ▁the ▁aircraft ▁encountered ▁ic ing ▁conditions ▁and ▁level led ▁off ▁at ▁ 1 7 , 8 0 0   ft , ▁continu ing ▁at ▁this ▁alt itude ▁for ▁approximately ▁ 9 ▁minutes . ▁With ▁ic ing ▁conditions ▁pers isting , ▁the ▁crew ▁initi ated ▁a ▁descent ▁to ▁F L 1 4 0 , ▁but ▁during ▁the ▁following ▁ 7 ▁minutes , ▁ic ing ▁conditions ▁significantly ▁w ors ened . ▁Control ▁of ▁the ▁aircraft ▁was ▁lost ▁shortly ▁after , ▁and ▁the ▁Sa ab ▁ 3 4 0 ▁impact ed ▁the ▁ground ▁in ▁a ▁remote ▁region ▁of ▁the ▁Río ▁Neg ro ▁Province , ▁between ▁the ▁villages ▁of ▁Los ▁Men uc os ▁and ▁Pra hu ani ye u . ▁ ▁The ▁aircraft ▁was ▁flying ▁at ▁night , ▁in ▁instrument ▁meteor ological ▁conditions ▁and ▁in ▁an ▁area ▁without ▁V H F ▁radio ▁coverage . ▁A ▁may day ▁call ▁was ▁received ▁by ▁the ▁crew ▁of ▁a ▁business ▁jet ▁flying ▁in ▁the ▁area ▁shortly ▁before ▁Fl ight ▁ 5 4 2 8 ▁was ▁lost . ▁Local ▁people ▁around ▁ ▁away ▁from ▁the ▁crash ▁site ▁saw ▁an ▁air plane ▁flying ▁extremely ▁low . ▁A ▁few ▁moments ▁later ▁they ▁heard ▁explos ions ▁and ▁noticed ▁black ▁smoke ▁coming ▁from ▁the ▁ground . ▁Fire fig h ters ▁arrived ▁at ▁the ▁scene ▁three ▁hours ▁later , ▁finding ▁no ▁surv iv ors .