The NTSB is asking people to send them photos of a skydiving plane after it crashed in Hawaii, killing 11 people.
They say the investigation will focus on damage the plane sustained to its tail section in a previous accident in 2016.
The twin-engine plane was carrying skydivers from the Oahu Parachute Company.
All 11 people on board were killed when the plane crashed near the airport's perimeter fence.