The FAA issued an Airworthiness Directive for the Eclipse 500 last month that, as of March 21, would limit the airplane’s maximum operating altitude to 30,000 feet. This supersedes an existing AD, issued in November 2008, that limited the very light jet to 37,000 feet or below in response to carbon build-up in the Eclipse’s Pratt & Whitney Canada PW610F-A engines that could cause engine surges and thus might “result in a necessary reduction in thrust.” The change was prompted by several incidents of engine surge the FAA believes were the result of hard carbon buildup on the static vanes.

According to the FAA, engine surges may call for a reduction in thrust and “decreased power for the affected engine and, in some cases, may result in flight and landing under single-engine conditions.” The FAA also notes it is possible this could affect both engines at the same time, requiring dual engine shutdown.

Eclipse Aerospace told AIN that it and P&WC are “in the final stages of completing a new combustion liner for the engine to solve the problem and return the EA-500 to 41,000 feet.”

Mason Holland, Eclipse Aerospace chairman and CEO, said based on the data Eclipse gathered, P&WC, Eclipse and Transport Canada collectively agree that rather than superseding the pre-existing 37,000-foot restriction, the AD should be revised to include a time limit when flying above 30,000 feet.

“The data supports that carbon builds up in no appreciable amounts on any flight above 30,000 feet until the airplane has been in that environment for more than 85 minutes,” Holland said.

“This is a short-term issue. P&WC’s new combustion liner has already been flight tested and P&WC and Eclipse are in the final stages of getting it certified. The new combustion liner will solve the problem and return the EA-500 to its original 41,000-foot status. We expect that fix to be on the market in approximately 60 days [as of March 16].” Holland noted both ADs are specific to Eclipse aircraft.

“P&WC has said if you’re protected under its service plan [ESP] there would be no charge. At this point Eclipse Aerospace does not have insight as to pricing should you not be under the P&WC ESP,” Holland told AIN.