Another Suggestion
The Red Oxx ES Aviator bag might also be an option. 16" X 12" X 8". Unstructured rectangular kit bag. Should accommodate most of your gear, especially if you take the previous advice and reduce it by a fraction. I use an Ebags medium packing cube containing my clothing on either side and then sandwich any more important items in between. A 15" packing folder will also fit to help with structure. It is compliant with "personal item" dimensions. The fact that it is unstructured, it can be "adjusted" to fit into just about any available space. Wear the jacket / blazer onto the flight.
Last edited by LiveOak; Oct 24, 2016 at 9:59 am
Reason: additional info