Removing the rear hatch will allow scientists a chance to study a section of the sub that they have not been able to get to since it was raised more than six years ago.
The rear hatch also contains a glass view port which must be removed before scientists can conserve the Hunley.
With the rear hatch locked "the story turns back to the front tower and why was it unlocked," McConnell said. "Did it get damaged or did he (Dixon) have it unlocked for a purpose?"
McConnell said the explanation may turn again to whether the crew suffocated, perhaps miscalculating the amount of oxygen they had.
One important clue will be an X-ray of the valves of the pumping system which are now encrusted with sediment.
The position of the valves should indicate whether the pump was set to take water in or out of the ballast tanks or, in the event the Hunley had taken on water, to pump it out of the crew compartment, McConnell said.
