▁to ▁the ▁R AF . ▁ ▁The ▁H eng ist ▁had ▁a ▁distinct ive ▁appearance ▁with ▁cur ved ▁upper ▁and ▁lower ▁surfaces ▁and ▁a ▁flat ▁s ided ▁fus el age . ▁ ▁Oper ational ▁history ▁Two ▁H eng ist ▁M k ▁Is ▁were ▁delivered ▁to ▁the ▁Gl ider ▁Pil ots ' ▁Ex erc ise ▁Unit ▁while ▁others ▁were ▁issued ▁to ▁experimental ▁units ▁or ▁remained ▁in ▁storage . ▁Production ▁was ▁halt ed ▁when ▁W aco ▁Had rian ▁gl iders ▁became ▁available ▁under ▁le ase - l end . ▁As ▁a ▁back - up ▁type , ▁it ▁saw ▁no ▁oper ational ▁service ▁and ▁was ▁ph ased ▁out ▁of ▁service ▁in ▁ 1 9 4 6 . ▁ ▁Spec ifications ▁( H eng ist ▁M k ▁I ) ▁ ▁See ▁also ▁ ▁References ▁ ▁Notes ▁ ▁Bibli ography ▁▁ ▁Bishop , ▁Chris . ▁The ▁Encyclopedia ▁of ▁We ap ons ▁of ▁World ▁War ▁II : ▁The ▁Com pre h ensive ▁Guide ▁to ▁Over ▁ 1 , 5 0 0 ▁We ap ons ▁Systems , ▁In cluding ▁T anks , ▁Small ▁Ar ms , ▁War plan es , ▁Art illery , ▁Sh ips ▁and ▁Sub mar ines . ▁New ▁York : ▁Ster ling ▁Publishing ▁Company , ▁Inc ., ▁ 2 0 0 2 . ▁. ▁▁ ▁Brown , ▁Robert ▁G . ▁On ▁the ▁Edge : ▁Personal ▁F lying ▁Exper ien ces ▁During ▁the ▁Second ▁World ▁War . ▁ ▁Ren f rew , ▁Ontario , ▁Canada : ▁General ▁Store ▁Publishing ▁House , ▁ 1 9 9 9 . ▁.