115012a0_e_Raiders___First_Joint_Action__3
[0] Departure from San Francisco [1] Low visibility [2] To prevent observation in and about San Francisco from deducing the mission of a task force accompanying a carrier whose flight deck was loaded with B-25’s. [3] 
Desirable that the departure of the Hornet be under conditions of low visibility.
Doolittle Raiders - First Joint Action
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