The NTSB recently posted on its Web site final reports on its investigations into two fatal business jet accidents. Challenger 600 N873G crashed during takeoff in icing  conditions from Montrose, Colo., on Nov. 28, 2004, (www.ntsb.gov/publictn/2006/AAB0603.htm) and Learjet 24B N600XJ made a controlled flight into terrain near Helendale, Calif., on Dec. 23, 2003 (www.ntsb.gov/publictn/2006/AAB0604.htm).