But Tuesday's16 July preliminary report by federal
safety investigators leaves many questions unanswered.
For example, the National Transportation Safety Board described four power failures that beset the
984-foot (300-meter) ship. Reasons for three of them are yet to be explained,
including two that occurred right before the crash.
Here's what we know and don't know about the
problems on the ship before the disaster:
HOW MANY TIMES DID THE SHIP LOSE POWER?
The Dali suffered four blackouts in roughly 10
hours: two the day before the crash and two in the minutes before.