cog cogwheel geared gears machine machinery mechanical mechanism metal rust rusted toothed wheel transmission aerospace air aircraft aviation axle blade bolt close-up closeup color detail engineer engineering equipment flight fly flying hazard head heavy helicopter industry mechanics part power powerful rivet rotate rotating rotation speed steer stop technology top transport transportation turn turning vehicle wheel bucket clean cleaning cleanliness cleanness cleanup deterioration disinfect disinfection foot-pedal galvanised galvanized health hygiene hygienics maneuvrability manoeuvrability metal-mechanism mobility mop mop-bucket mop-pail mopping old roller-wringer-mop-bucket rusty sanitation sanitising sanitizing steel-wringing-system treatment washing wringer-mop-bucket blades chopper propeller rotor spin wing balance tail