37280 - Aircraft parts & Auxiliary equipment (Miscellaneous)
37281 - Aircraft parts & Accessories (General)
3728113 - - Aircraft mechanical power transmission equipment for Military aircraft & all other Aircraft built to military specifications
3728115 - - Aircraft mechanical power transmission equipment for Civilian aircraft
3728173 - - Aircraft hydraulic subassemblies for Military aircraft & all other Aircraft built to military specifications
3728175 - - Aircraft hydraulic subassemblies for Civilian aircraft
3728183 - - Aircraft pneumatic subassemblies for Military aircraft & all other Aircraft built to military specifications
3728185 - - Aircraft pneumatic subassemblies for Civilian aircraft
3728194 - - Aircraft landing gear for Military aircraft & all other Aircraft built to military specifications
3728195 - - Aircraft landing gear for Civilian aircraft
3728198 - - Aircraft subassemblies & other Parts (except aircraft propellers & Helicopter rotors) for Military aircraft & all other Aircraft built to military specifications
3728199 - - Aircraft subassemblies & other Parts (except aircraft propellers & Helicopter rotors) for Civilian aircraft
372819X - - Aircraft parts & Auxiliary equipment (Miscellaneous)
37282 - Aircraft propellers & Helicopter rotors
3728210 - - Complete propellers, excl helicopter rotors
3728231 - - Propeller blades
3728251 - - Propeller parts, except propeller blades
3728261 - - Helicopter rotors & Parts
3728299 - - Aircraft propellers & Propeller parts (Miscellaneous)
37283 - Research & Development on aircraft parts
3728313 - - Research & Development on aircraft parts for Military aircraft & all other Aircraft built to military specifications
3728315 - - Research & Development on aircraft parts for Civilian aircraft
3728399 - - Research & Development on aircraft parts (Miscellaneous)
37284 - Aircraft hydraulic & Pneumatic subassemblies
3728473 - - Aircraft hydraulic subassemblies for military aircraft & all other Aircraft built to military specifications
3728475 - - Aircraft hydraulic subassemblies for Civilian aircraft
3728483 - - Aircraft pneumatic subassemblies for military aircraft & all other Aircraft built to military specifications
3728485 - - Aircraft pneumatic subassemblies for Civilian aircraft
37285 - Aircraft parts & Auxiliary equipment, excl hydraulic & Pneumatic subassemblies & Engines
3728513 - - Aircraft mechanical power transmission equipment for military aircraft & all other Aircraft built to military specifications
3728515 - - Aircraft mechanical power transmission equipment for Civilian aircraft
3728594 - - Aircraft landing gear for military aircraft & all other Aircraft built to military specifications
3728595 - - Aircraft landing gear for Civilian aircraft
3728598 - - Other Aircraft subassemblies & Parts for military aircraft & all other Aircraft built to military specifications
3728599 - - Other Aircraft subassemblies & Parts for Civilian aircraft
3728XX0 - - Aircraft parts & Auxiliary equipment (Miscellaneous - Volume)
3728XX2 - - Aircraft parts & Auxiliary equipment (Miscellaneous - Speciality)