THIS IS IT! Crew members of "Dave's Dream," B-29 Super Fort atomic bombing plane, prepare for the bombing mission. Major Woodrow P. Swancutt, center, "pulls through" a blade of 
one of the ship's huge four-bladod Hamilton propellers. Propellers are turned through four complete revolutions in this fashion in order to determine that engine cylinder heads are free from accumulated oil.
United States. Joint Task Force One
1946
<p>Operation Crossroads : the official pictorial record
by United States. Joint Task Force One
</p>
Publication date 1946