ers , ▁firing ▁in ▁pairs ▁ ▁R CS ▁prop ell ants : ▁MM H / N 2 O 4 ▁ ▁R CS ▁prop ell ant ▁mass : ▁▁ ▁Dr inking ▁water ▁capacity : ▁▁ ▁W aste ▁water ▁capacity : ▁▁ ▁CO 2 ▁scr ub ber : ▁l ith ium ▁hydro x ide ▁ ▁Od or ▁absor ber : ▁activ ated ▁char co al ▁ ▁Electric ▁system ▁batter ies : ▁three ▁ 4 0 ▁amp ere - hour ▁silver - z inc ▁batter ies ; ▁two ▁ 0 . 7 5 ▁amp ere - hour ▁silver - z inc ▁py rote chn ic ▁batter ies ▁ ▁Par ach utes : ▁two ▁ ▁con ical ▁rib bon ▁dro gue ▁par ach utes ; ▁three ▁ ▁ring shot ▁pilot ▁par ach utes ; ▁three ▁ ▁rings ail ▁main ▁par ach utes ▁ ▁Service ▁module ▁( SM ) ▁ ▁Const ruction ▁The ▁service ▁module ▁was ▁an ▁un press ur ized ▁cyl ind rical ▁structure , ▁meas uring ▁ ▁long ▁and ▁ ▁in ▁diameter . ▁The ▁interior ▁was ▁a ▁simple ▁structure ▁consisting ▁of ▁a ▁central ▁tunnel ▁section ▁ ▁in ▁diameter , ▁surrounded ▁by ▁six ▁pie - sh aped ▁se ctors . ▁The ▁se ctors ▁were ▁to pped ▁by ▁a ▁forward ▁bulk head ▁and ▁fair ing , ▁separated ▁by ▁six ▁radial ▁be ams , ▁covered ▁on ▁the ▁outside ▁by ▁four ▁h oney comb ▁pan els , ▁and ▁supported ▁by ▁an ▁a ft ▁bulk head ▁and ▁engine ▁heat ▁shield . ▁The ▁se ctors ▁were ▁not ▁all ▁equal ▁ 6 0