Challenger Icing Issue Subject of ADI

Operators of all U.S.-registered Challenger 600s, 601s and 604s and Canadair Regional Jets, which are derived from the business jet, must incorporate flight manual revisions to ensure that before takeoff the “wing leading edge and upper wing surface are completely free of ice, frost, snow or slush,” under a new AD. The FAA directive (AD 2005-04-07) followed an identical AD from Transport Canada. In addition to a visual inspection, the ADs require a “tactile means” of identifying potential contamination. Investigators concluded that frost on the wings caused a Challenger 604 to crash on takeoff on Jan. 4, 2002, in Birmingham, England. Ice or snow on the wings is suspected in the ongoing investigation of the Nov. 28, 2004, fatal takeoff accident involving a Challenger 601 in Montrose, Colo.