The　refined　aerial　operations　of　the　unmanned　aerial　manipulator　(UAM)　have　been　extensively　studied　for　the　last　decades.　Usually,　UAM　operations　are　accompanied　by　several　phases,　such　as　free　flight,　contact　operations,　and　separation.　A　great　challenge　is　proposed　for　switching　operations　in　different　environments　and　the　high-precision　contact　force　requirements　of　UAM　control,　so　this　paper　conducts　control　stability　research　in　the　case　of　dynamic　differences　between　free　flight　and　contact　operation　for　the　UAM　system.　First,　a　hybrid　force/position　control　strategy　is　proposed　for　switchable　UAM　system,　among　them,　the　adaptive　sliding　mode　control　method　based　on　the　interference　observer　is　utilized　in　the　free　flight　phase,　and　the　adaptive　impedance　force　control　method　is　employed　in　the　contact　operation　phase,　where　the　adaptive　estimation　method　is　designed　to　perform　on-board　manipulator　contact　force　estimation.　Then　a　robust　adaptive　control　strategy　is　proposed　for　the　attitude　loop　to　compensate　for　the　torque　disturbance　generated　during　the　contact　operation　phase.　Meanwhile,　the　stability　of　the　switching　system　is　analyzed　through　the　continuous　Lyapunov　function　to　prove　the　stability　of　the　switching　process.　Finally,　the　effectiveness　and　superiority　of　the　proposed　schemes　are　verified　through　contact　operation　simulations　and　experiments.　Note　to　Practitioners-This　work　is　motivated　by　the　contact　force　tracking　of　an　UAM　without　force　sensor.　In　recent　years,　hybrid　force/position　control　has　been　widely　used　in　UAM.　However,　force　measurement　is　required　at　the　end-effector　and　the　object　in　most　studies.　The　proposed　method　divides　the　contact　operation　process　into　free　flight　and　contact　operation　stages.　In　the　free　flight　stage,　it　is　not　necessary　to　know　the　prior　information　of　the　environment　accurately　(i.e.　the　external　disturbance　of　slowly　varying　or　known　upper　bound),　and　the　disturbance　observer　is　adopted　to　compensate　for　the　disturbance　caused　by　the　external　environment.　In　the　contact　operation　stage,　the　impedance　force　control　method　is　used　for　force　tracking,　which　reduces　the　complexity　and　quality　of　the　end-effector.　At　the　same　time,　The　shock　caused　by　the　switch　from　free　flight　to　contact　operation　is　reduced　by　calculating　the　appropriate　controller　parameters　using　the　Lyapunov　function.　The　proposed　method　is　a　promising　solution　for　real　applications　and　is　validated　via　simulation　and　indoor　contact　experiments.　The　experimental　results　show　that　the　proposed　method　has　better　stability　and　accuracy　than　the　existing　methods,　and　can　be　extended　to　industrial　inspection,　component　processing,　aerial　operation,　etc.