The FAR Part 21.35 function and reliability flight testing would include turbine-powered airplanes with maximum takeoff weights of 6,000 lb. or less under a notice of proposed rulemaking (NPRM) released by FAA on April 16.

Currently, FAR Part 23 function and reliability testing only applies to new aircraft with higher gross takeoff weights. The NPRM might be called the Eclipse 500 rule because one of FAA’s prime motivations, according to the document, was the organization’s recent type certification process associated with the Eclipse 500.

“After reviewing the Eclipse SCR [Special Certification Review] and the EA-500 certification program, the FAA reviewed the likelihood that function and reliability flight testing requirements might have preventatively identified problems encountered by the EA-500 when it entered service,” the NPRM notes. As examples, the proposed rule cites Eclipse 500’s pitch and rudder trim malfunctions, moisture trapped in the pitot static system, engine surging caused by carbon deposits on the high pressure turbine inlet vanes, brake maladies and tire problems.

“Revising the applicability [for function and reliability flight testing] is necessary because advancements in aviation technology have invalidated the reasons for excluding these airplanes . . . FAA has determined that most, if not all, of these airplane designs would benefit from the function and reliability flight testing requirement.”

The NPRM potentially has an impact on certification requirements for proposed personal jets, including the Cirrus Vision, Diamond D-Jet and Stratos 714 VLJs, among other designs. FAA believes that function and reliability flight testing will add 165 hours to flight testing, if a new VLJ is using a proven, certified engine, such as the Williams FJ33 turbofan. If both the engine and airframe are new, an additional 330 hours will be required.

Comments on the proposed rule, Docket Number FAA-2010-0218, may be submitted electronically at www.regulations.gov on or before July 8, 2010.

Stratos 714 VLJ photo: Stratos