Engine Damage Not Caused by Volcanic Ash

Dramatic photos circulating on the Internet purporting to show a Williams International FJ44-3A-24 installed on a Cessna Citation CJ2+ destroyed by exposure to volcanic ash from the recent eruption in Iceland are “complete fiction,” according to Brad Thress, Cessna vice president of product support. The incident occurred about a month before the April eruption, he said. “It’s viral,” Thress said. “We get hundreds of e-mails here…It’s interesting how things can take off on the Internet.” What caused the damage is a known issue with the engine’s diffuser, he said. Williams has already sent a letter to operators warning about the potential for the diffuser to fail. The failure mode is caused by a harmonic vibration that cracks the fuel manifold, and the engine company notified operators that signs of shifting or cracking of the diffuser include a shift in ITT, fuel odor in the cabin or difficulty removing the diffuser or start nozzle, according to Thress. Cessna is planning to release an alert service letter on this issue, and diffusers are being replaced during the next scheduled maintenance event. “It is a fleet issue,” he said, “not related to volcano activity.”