Whats required for "Normal" catergory design under FAR 23?
Please forgive my ignorance, but I am a pilot from Australia and I am having some troubles with the national regulator (CASA) with regards to the operations our aircraft is allowed to perform. We own a Pipistel Virus SW (ICAO code PIVI) and we have been told by CASA that we cannot use the aircraft for photography work because it has not been designed to, quote "Normal Category Type Design (FAR 23)".
I would now like to see where the aircraft doesn't meet the normal category type design specifications in order to work out whether it is reasonable for CASA to put such a broad ban on us. Can anybody tell me, or ideally provide me with, the specifications that have to be meet to fit into the normal catergory? Are they with regard to performance, maintenance, manufacturing standards or a combination?
Thanks in advance.