Explanatory notes
… parts of this heading include : (I) Parts of balloons and dirigibles , such as : (1) Nacelles. (2) Envelopes … (6) Stabilisers and rudders . (7) Propellers for dirigibles . (II) Parts of aircraft, manned or unmanned, … etc.). (2) Wings and their components (spars, ribs, cross-members). (3) Control surfaces, whether or …