The precise cause of the deadly midair collision between an American Airlines passenger jet and an Army helicopter in Washington last week will not be determined until the National Transportation Safety Board completes its full investigation, which could take a year or longer. However, the NTSB will likely release a preliminary report within 30 days.

In the meantime, based on the limited information that has trickled out, people have begun to form their own opinions. And the conversation keeps returning to two explanations. Both are deeply troubling.