first of thanks for the rep and i'm honored to join the jumbo group. and no i haved fitted other cargo in the bay. you can place docking ports where you want in the cargo bay, the plane is pretty big so I do not think it will create many problems. the orange tank fits pretty snuk, so thats how big you object can be. it fly's pretty good emty, i just landed on the runway after a trip to orbit (its a bit more wobbly) no fuel pumping needed for more jumbo you need a lifter to put it in the cargobay (i may try to build one)