The Virginia State Police helicopter that crashed on August 12, killing both officers on board, was flying at 2,200 feet when it abruptly turned to the right and began to dive, says radar data acquired by the NTSB. The NTSB interviewed nearly 40 witnesses who generally confirmed that the helicopter “began a rolling oscillation, began to spin (rotate about the vertical axis), and then descended in a 45° nose down attitude, while continuing to spin until it was lost from sight below the tops of the surrounding trees.”
Source: avwebNTSB Issues Report on Police Helo Crash