Still, if they asphyxiated the bodies... you gotta get rid of them. Would YOU want to fly around with 230 rotting corpses? So, if they landed, logically they offloaded the bodies. Where are they?
How do they refuel the plane without anyone knowing?
Remember, we are dealing with death-worshipping muzzies here, first. Second, I think they WOULD get rid of the bodies for weight/range but that would be a monumental undertaking in strength and manpower....almost inconceivable unless there were many hijacker/terrorists. I've done fireman carry drills in full-battle rattle. I'd be pooped after carrying 10 bodies and possibly muscle fatigue/failure.
This is going to be the BIG mystery of this century if never found.
I guess I'll sum up what a former CIA guy said on the news this morning, "If it is terrorism, it ain't the same type of terrorists ive been hunting and killing since the mid-1990s....they aren't that technically proficient, smart, or lucky".
Corpses are easy - throw them out of the plane over the ocean. Heck, in South America they don’t even kill people before they do that.