, ▁Sau nd ers - R oe ▁submitted ▁their ▁detailed ▁proposal . ▁The ▁proposed ▁single - se at ▁aircraft , ▁designated ▁as ▁the ▁SR . 5 3 , ▁was ▁capable ▁of ▁very ▁high ▁spe eds , ▁being ▁project ed ▁as ▁being ▁capable ▁of ▁a ▁top ▁speed ▁of ▁ ▁when ▁at ▁an ▁alt itude ▁of ▁, ▁and ▁a ▁rate ▁of ▁clim b ▁of ▁ ▁per ▁minute ▁around ▁an ▁alt itude ▁of ▁. ▁An ▁auxili ary ▁dispos able ▁under car riage ▁could ▁be ▁used ▁for ▁take offs , ▁along ▁with ▁cord ite - based ▁boost er ▁rock ets . ▁In ▁the ▁event ▁of ▁an ▁emer gency , ▁the ▁entire ▁cabin ▁would ▁have ▁originally ▁been ▁j ett ison ed ▁as ▁a ▁means ▁of ▁providing ▁the ▁pilot ▁with ▁a ▁means ▁of ▁escape ; ▁due ▁to ▁the ▁work ▁involved ▁in ▁developing ▁this , ▁it ▁was ▁instead ▁replaced ▁by ▁a ▁more ▁standard ▁e jection ▁seat ▁arrangement . ▁The ▁firm ▁had ▁quickly ▁identified ▁that ▁that ▁original ▁un power ed ▁' g lide ▁home ' ▁approach ▁to ▁be ▁dangerous ▁and ▁expensive ; ▁they ▁approached ▁the ▁Air ▁Ministry ▁with ▁their ▁concept ▁of ▁a ▁secondary ▁jet ▁engine ▁for ▁the ▁purposes ▁of ▁power ing ▁the ▁aircraft ' s ▁journey ▁home . ▁The ▁Ministry ▁was ▁enthus i astic ▁on ▁this ▁concept ; ▁in ▁May ▁ 1 9 5 1 , ▁all ▁interested ▁companies ▁were ▁asked ▁to ▁examine ▁this ▁arrangement . ▁ ▁The ▁SR . 5 3 ▁was ▁a ▁sle ek ▁aircraft ▁with ▁a ▁sharp ly - point ed ▁nose , ▁delta - like ▁wing ,