Is the Soloy Dual Pac recognised as two engines or one engine? The Soloy Dual Pac apparently allows two engines to rotate one propeller -- here's a picture of it on an Otter:



Is this recognised as a centreline thrust twin engine aircraft, a "standard" twin engine aircraft or just an aircraft with a single engine for FAA certification? What about for pilot licensing?
According to the certificate is a


  Twin Power Section Turboprop


and, later, note 7: (emphasis mine)


  This engine is certificated as a unit comprising two separate power sections with the capability of single engine operation with either power section alone in multi-engine airplanes. The unit is also approved as a single engine with either or both engines operating continuously. 


No explicit remark is given about pilot licensing, but given the note reported, I would say that a licence for a single engine is sufficient.