USAF figured that upgrading RQ-4 could cost less than $4 billion

Earlier estimate of upgrading the RQ-4 with new sensors for $4 billion might be too conservative, Lt. Gen. Robert Otto, deputy chief of staff for intelligence, surveillance and reconnaissance believes it can be done at half the price.

Global Hawk prepares for flying mission
U.S. Air Force photo/Staff Sgt. Andy M. Kin

The Global Hawk is in need of a new electro-optical sensor and a wide field of view optical camera in order to replicate the mission performed by U-2.

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