As the recording began, the flight crew was discussing an existing problem with the airplane's stabilizer trim,
The availability of electronic imagery would help resolve issues surrounding flight crew actions in the cockpit. For example, it would tell us which pilot was at the controls and what controls were being manipulated.
The airplane's out-of-trim condition became worse as the crew attempted to diagnose or correct the problem, ... The crew had difficulty controlling the airplane's tendency to pitch nose down. The airplane descended, but the crew was able to (stop) the descent.