day 20 egg cracked wide open - dead chick

[mandolinmama]

It's day 20 for our hatch and when I looked in the bator awhile ago noticed that one of the eggs had some yolk out of it. I took the egg out and cracked it open. The chick looked pretty much developed. I know that I did have a couple of eggs in there with air cells that seemed too large. Could that have been the problem? Any thoughts as to why this happened?
Thanks

 

[kstaven]

Normally it is a weak spot on the shell. The chick growing and moving adds pressure to the shell and it cracks.