You can find documentation about the P180 Avanti II at:

http://www.easa.eu.int/doc/Certification/Design_Appro/Aircrafts/TCDS%20EASA%20A%20059%20P%20180%20Iss%203.pdf
http://www.piaggioaero.com/en/products/aircraft/p180/spec.php
http://www.piaggioaero.com/cuploads/AvantiII_Cut-Away.pdf
http://www.piaggioaero.com/cuploads/AvantiIISpecification.pdf
