Federal investigators are expected torelease a preliminary report this week about last week's plane crash on Route 287.

The National Transportation Safety Board is expected to release a factual report, but a final report on what caused the crash could take up to a year or more to complete.

The single-engine turboprop spiraled out of the sky shortly after taking off from Teterboro Airport, broke apart and crashed in Harding Township last Tuesday.

Killed were Jeffrey Buckalew, an investment banker in New York; his wife, Corrine; their two children; and colleague Rakesh Chawla, 36. They were en route to Georgia.

Before the crash, Buckalew radioed air traffic controllers to say ice was accumulating on the plane. Other pilots in the area reported similar problems.

Investigators: Too early to draw conclusions on ice in I-287 crash News conference on Morris County plane crash VIDEO: Plane crash path, debris litters area around Route 287 Many on the ground call themselves lucky following plane crash Witnesses recount Morris County plane crash