AT 21a

From Inventing aviation
Revision as of 08:34, 18 August 2023 by AvionHerbert (talk | contribs)
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
Jump to navigation Jump to search

This is an instance in which the original patent document by which we found the classification does not display the nature of the classification. This classification may involve peculiarities of design and technical principle which are not at all exclusive to aeronautics. The classification has nevertheless entered our data via patents covering inventions which do apply to aeronautics and aviation.

This wiki has 1 patents in category "AT 21a".

Patents in category AT 21a

Enclosing categories AT 20, Austrian patent classifications, Patent classification systems
Start year
End year