The National Transportation Safety Board said in the report Tuesday that the wreckage has been kept for further examination.
The World War II-era bomber crashed and burned after experiencing mechanical trouble on takeoff from Bradley International Airport the morning of Oct. 2.
The plane was carrying 13 people, and the two pilots were among those killed.
A third member of the flight crew and four passengers were seriously injured. Another passenger and one person on the ground suffered minor injuries.
The bomber was a familiar sight over Sacramento skies. Last year it flew at McClellan Air Field.
WATCH: Dave Bender speaks about his ride aboard the bomber.
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