We took a maxi cosi pebble plus and our bugaboo chameleon, as well as a baby zen yoyo with us last year as we went to china for a month. I bought a padded car seat bag from amazon and checked it in, plus we padded it out with nappies and blankets etc. We also bought the bugaboo travel bag and checked the pushchair in at the desk as well. Both these bags are massive so provided extra packing space and are padded so nothing got damaged.
we then took the yoyo to the gate and put in the overhead locker....