▁by ▁Dr . ▁Brun olf ▁Ba ade , ▁at ▁OK B - 1 , ▁in ▁ 1 9 4 7 . ▁The ▁six ▁J um o ▁ 0 0 4 ▁engines ▁of ▁the ▁EF - 1 3 1 ▁were ▁replaced ▁by ▁two ▁Mik ul in ▁AM - T K R D - 0 1 ▁ax ial ▁flow ▁tur bo jets , ▁r ated ▁at ▁ 3 2 . 3 7 2   k N ▁( 7 , 2 8 0   lb ) ▁thrust , ▁in ▁large ▁nac elles ▁attached ▁to ▁the ▁unders ide ▁of ▁the ▁wing ▁at ▁the ▁same ▁position . ▁ ▁Using ▁the ▁air frame ▁of ▁the ▁second ▁EF - 1 3 1 ▁prototype , ▁the ▁' 1 4 0 ' ▁was ▁very ▁similar ▁in ▁appearance , ▁and ▁to ▁its ▁for eb ear ▁J unk ers ▁Ju ▁ 2 8 7 , ▁with ▁the ▁classic ▁J unk ers - style ▁crew ▁compart ment ▁in ▁the ▁nose , ▁wings ▁swe pt ▁forward ▁ 1 9 ° 5 0 ' ▁with ▁marked ▁di hed ral , ▁and ▁the ▁unders lung ▁engine ▁nac elles ▁extending ▁forward ▁of ▁the ▁leading - edge . ▁Const ruction ▁was ▁of ▁al umin ium ▁al loy ▁str essed ▁skin , ▁with ▁a ▁semi - mon oco que ▁fus el age , ▁wings ▁with ▁multiple ▁sp ars ▁covered ▁with ▁str essed ▁skin ▁pan els , ▁and ▁high ▁strength ▁steel ▁for ▁highly ▁str essed ▁parts . ▁Def ensive ▁arm ament ▁consisted ▁of ▁V DB - 6 ▁d ors al ▁and ▁N