Hi Cod, in response to twiggs reply I would also check that the airline does allow you to bring on your own car seat. The airline i work for dosent allow it so there may also be others that dont. However they will have there own on board for you to use.
I agree with lex that he will probably be to big for a bassinet but try to get seated at a bulkhead. However dont be dissapointed if you dont get there because they give priority of those seats to disabled pax or small babys.
Hope you have a nice flight.