Like I said before anything is possible if you have the money to pay for it.

If for example you buy a BN-2, change the engine, install floats and reinforce the structure, a single visit of FAA inspectors is enough or it's a reactively long process ? does it depend on the usage, private or commercial ?

If for example you buy a BN-2, change the engine, install floats and reinforce the structure, a single visit of FAA inspectors is enough or it's a reactively long process ? does it depend on the usage, private or commercial ?

Well you could make it experimental or deal with the testing to get a supplemental type certificate (STC).

Well you could make it experimental or deal with the testing to get a supplemental type certificate (STC).

So if, I understand everything :Private use : experimental and supplemental type certificate.Commercial : only STC.In most case scenario, how long does it take to recieved a supplemental type certificate ?

In most case scenario, how long does it take to recieved a supplemental type certificate ?

Years at a cost that would make the venture not worthwhile. Engineering alone would cost you $500k+ easy and that doesn't include the actual retrofit or tweaking after flight testing.STC's, especially power plant STC's, are very expensive to get certified and take a long time in today's FAA. That is why the diesel conversion for the 172 is $125,000 to $175,000 retail. Also since there are three types of engines currently available from the factory including a turbine the FAA won't be as helpful in getting the STC completed. If you are planning on using the modification for passenger transport the FAA will probably through you into a Original Design Approval Process as well. It is just a more in depth review/certification process for complex modifications to an aircraft/engine. Honestly factory support would be the only way to get a modification done to the BN-2.

Years at a cost that would make the venture not worthwhile. Engineering alone would cost you $500k+ easy and that doesn't include the actual retrofit or tweaking after flight testing.STC's, especially power plant STC's, are very expensive to get certified and take a long time in today's FAA. That is why the diesel conversion for the 172 is $125,000 to $175,000 retail. Also since there are three types of engines currently available from the factory including a turbine the FAA won't be as helpful in getting the STC completed. If you are planning on using the modification for passenger transport the FAA will probably through you into a Original Design Approval Process as well. It is just a more in depth review/certification process for complex modifications to an aircraft/engine. Honestly factory support would be the only way to get a modification done to the BN-2.

Thanks for this detail answer. very helpful.