Kenneth Meyer

Document ID: FAA-2008-1232-0002
Document Type: Public Submission
Agency: Federal Aviation Administration
Received Date: November 25 2008, at 01:33 PM Eastern Standard Time
Date Posted: November 26 2008, at 12:00 AM Eastern Standard Time
Comment Start Date: November 24 2008, at 12:00 AM Eastern Standard Time
Comment Due Date: January 23 2009, at 11:59 PM Eastern Standard Time
Tracking Number: 807bf423
View Document:

This is comment on Rule

Airworthiness Directives: Eclipse Aviation Corporation Model EA500 Airplanes

View Comment

The discussion section of AD 2008-24-07 confirms the information that Eclipse 500 owners have received directly from the aircraft manufacturer and the engine manufacturer, namely: "When the PW610F-A engine is operated above 37,000 feet, for over an hour, AND WITH HIGH BLEED FLOW, hard carbon forms due to high local fuel air ratio near the combustor wall." (emphasis added) There is no need to restrict flight to 37,000 feet and below. According to the AD itself, a necessary prerequisite for the unsafe condition is high bleed flow. Therefore, not operating the aircraft above 37,000 feet with high bleed flow is all that is required to address the unsafe condition. Setting the cabin and cockpit desired environmental temperatures to 68F keeps these engines from going into high bleed flow and prevents the unsafe condition that the AD addresses. Therefore, a limitation regarding temperature setting above 37,000 feet would be equally-effective and far less restrictive than the one actually proposed in the AD.