Not a pilot etc but still prefer to travel light cos waiting at carousels is a pain in the backside....
I use one of these, it has enough space for couple days worth of clothing along with two laptops, cables and all the rest of the typical stuff that gets dragged about an airport
http://www.delsey.com/int/en/p/montm...124448000.html
I bought mine at Zaventem last year when my trusty Belkin rolling bag died on the travelator.......saw several crew with them, so they must be OK for squirreling into the confines of a cockpit