. 3 0 . ▁It ▁first ▁fle w ▁on ▁ 1 2 ▁January ▁ 1 9 3 2 , ▁initially ▁power ed ▁by ▁the ▁ 1 7 2   k W ▁( 2 3 0   hp ) ▁ 9 Q a ▁engine ▁variant . ▁ ▁In ▁ 1 9 3 5 ▁these ▁were ▁replaced ▁by ▁ 2 4 0   k W ▁( 3 2 0   hp ) ▁ 9 Q bs . ▁ ▁In ▁this ▁form ▁the ▁outer ▁engines ▁remained ▁un cow led ▁but ▁the ▁central ▁one ▁had ▁a ▁long ▁ch ord ▁N AC A ▁cow ling . ▁ ▁Oper ational ▁history ▁The ▁D . 3 1 ▁was ▁owned ▁by ▁the ▁Centre ▁d ' E ss ais ▁de ▁Mat éri els ▁A éri ens ▁( CE MA ) ▁at ▁Villa cou bl ay . ▁it ▁remained ▁registered ▁there ▁in ▁June ▁ 1 9 3 5 ▁but ▁had ▁gone ▁two ▁years ▁later , ▁prompt ing ▁spec ulation ▁that ▁it ▁may ▁have ▁been ▁used ▁by ▁Republican ▁forces ▁in ▁the ▁Spanish ▁Civil ▁War . ▁ ▁Vari ants ▁D . 3 0 ▁Single - engine ▁first ▁prototype . ▁Em pty ▁weight ▁ 2 , 4 7 6   kg ▁( 5 , 4 5 7   lb ), ▁gross ▁weight ▁ 4 , 4 8 6   kg ▁( 9 , 8 9 0   lb ). ▁D . 3 1 ▁Three - engine ▁second ▁prototype . ▁ ▁Spec ifications ▁( D . 3 1 ) ▁ ▁References ▁ ▁Category : 1 9 3