The helicopters that crashed last month in Hammonton, New Jersey, were flying closely together before they collided, a new National Transportation Safety Board report says.
The crash killed both helicopter pilots: Michael Greenberg, 71, of Sewell, and Kenneth L. Kirsch, 65, of Carney's Point. No passengers were on board either aircraft.
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The NTSB released a preliminary report on the crash Wednesday. A final report that offers the NTSB's conclusions on the cause will be issued once its investigation is complete. That is expected to take 12-18 months, NBC10 reported.
The helicopters left the Vineland-Downstown Airport at 9:48 a.m. on Dec. 28 to fly to Hammonton Municipal Airport, where they arrived at 9:58 a.m., the preliminary report says. They then departed the Hammonton Airport just before 11:25 a.m.
Surveillance footage shows the helicopters, an Enstrom 280C and an Enstrom F-28A, were flying closely together in a slightly staggered pattern until they collided, the report says. One helicopter immediately began falling to the ground, and the other moved up sharply and leveled out. It then moved side-to-side and began a sharp descent.
The report does not say which helicopter struck the other, but it says there was a paint transfer from what appeared to be the tail rotor of the Enstrom 280C on the Enstrom F-28A.
The helicopters crashed into a field about 1.5 miles from the airport. The debris path was 1,211 feet long and included the main rotor blades and tail portions of both helicopter, plus the cone and tail rotor blades of the Enstrom 280C.
The Enstrom F-28A had damage to the body, tail cone, tail rotor and main rotor, but there were no signs of fire, the report says. The ground at the scene appeared to have been struck by the main rotors. The Enstrom 280C was primarily destroyed by a fire that began after it hit the ground. The blaze consumed most of the main body and rotor system. The aft portion of the tail showed damage that was consistent with an in-flight collision.