- sam pling ▁mission . ▁Ten ▁aircraft ▁were ▁initially ▁converted ▁from ▁C - 1 3 5 B ▁transport ▁aircraft ▁and ▁were ▁placed ▁in ▁service ▁with ▁the ▁ 5 5 th ▁We ather ▁Re con na issance ▁Squadron ▁at ▁McC le ll an ▁Air ▁Force ▁Base , ▁California , ▁with ▁the ▁Military ▁Airl ift ▁Command ▁( MA C ). ▁Det ach ments ▁were ▁located ▁at ▁various ▁bases ▁throughout ▁the ▁United ▁States ▁and ▁world wide . ▁The ▁aircraft ▁occasionally ▁took ▁on ▁other ▁roles ▁throughout ▁their ▁care ers ; ▁several ▁aircraft ▁were ▁tempor arily ▁assigned ▁to ▁the ▁ 1 0 th ▁Air bor ne ▁Command ▁and ▁Control ▁Squadron ▁at ▁R AF ▁M ild en hall ▁in ▁the ▁late ▁ 1 9 8 0 s ▁and ▁early ▁ 1 9 9 0 s ▁as ▁training ▁aircraft ▁so ▁that ▁the ▁unit ▁could ▁slow ▁the ▁accum ulation ▁of ▁flight ▁hours ▁on ▁its ▁EC - 1 3 5 H s , ▁while ▁others ▁served ▁as ▁staff ▁trans ports ▁on ▁an ▁as - ne eded ▁basis . ▁ ▁While ▁most ▁aircraft ▁were ▁placed ▁into ▁storage ▁in ▁the ▁early ▁ 1 9 9 0 s , ▁three ▁were ▁retained ▁for ▁further ▁use . ▁Serial ▁no .   6 1 - 2 6 6 6 ▁was ▁converted ▁to ▁an ▁NC - 1 3 5 ▁and ▁remains ▁in ▁service ▁as ▁a ▁test bed ▁for ▁RC - 1 3 5 ▁equipment ▁up gr ades . ▁Serial ▁no .   6 1 - 2 6 6 7 ▁was ▁upgrad ed ▁to ▁a ▁W C - 1