Eclipse 500 Operators Disagree with FAA on Carbon AD

 - December 4, 2008, 11:00 AM

When it issued Eclipse 500 Airworthiness Directive 2008-24-07, which becomes effective today, the FAA asked for comments from operators. The AD limits the Eclipse 500 to a maximum pressure altitude of 37,000 feet due to “several incidents of engine surge” of the jet’s Pratt & Whitney Canada PW610F-A engines. The surge is due to carbon buildup on the static vane during high bleed flow conditions. Apparently, commenters disagree with the FAA’s 37,000-foot limitation while a fix is under way. Eclipse 500 owner Robert Golo’s comment echoes others on the docket and suggests a simpler method to keep bleed air levels low: “If operations above 37,000 feet were to include a restriction to keep the cabin and cockpit air temperatures set at 68 degrees or below,” he wrote, “the bleed air would stay on LOW and no carbon buildup on the static vanes would occur. This has worked well since the problem was discovered months ago.” Pratt & Whitney Canada, said a spokeswoman, is “working closely with Eclipse Aviation to address this unexpected condition, which is unique to the engine model in this installation.”