main gear box / main rotor transmission

main rotor transmission / main gear box

main-rotor head / main-rotor hub

main-rotor hub / main-rotor head

transmission / gear box

rotor (system) gear box

tail rotor gear box

main gear box oil temperature indicator

gear reduction transmission

helical gear transmission

lateral dual rotor system / side-by-side rotor helicopter

main transmission oil temperature gauge

gearbox / gear box

aircraft accessory gear box

engine accessory gear box

intermediate gear box

rotor gear pump

intermediate reduction gear box

aft main rotor

main rotor brake

main rotor hub

blade tip light / main-rotor blade tip light

five-blade main rotor

forward main rotor

main rotor noise

main-rotor (hydraulic) collective pitch actuator

main-rotor axis

main-rotor blade

main-rotor blade durability

main-rotor blade tip light blade tip light

main-rotor brake

main-rotor collective pitch control rod

main-rotor diameter