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FAA National Policy - Clarification of Inspection and Overhaul Requirements Under Part 91

Tue, 10/24/2017 - 12:50

Hello Avmgr and Maint subscribers,


The purpose of this email is to ascertain what your interpretations as aviation department managers and maintenance personnel are concerning the FAA’s National Policy Notice N 8900.410 Effective Date: 3/31/17, regarding SUBJ:

Clarification of Inspection and Overhaul Requirements Under Part 91, which will be incorporated into FAA Order 8900.1 before this notice expires 3/31/18.


Please refer to the following link: for the complete text.



Paragraph 4. Background. There have been several recent issues surrounding the interpretation of whether compliance with the manufacturer’s recommended time between overhaul (TBO) intervals are required under Part 91.


Paragraph 5. Discussion. a.(1)(b)  Overhauls are Maintenance. By definition, overhauls are a form of maintenance, not inspection, and are not included in an inspection program. Overhauls are part of the maintenance program. Part 91 operators are not required to comply with a manufacturer’s entire maintenance program; as such, overhauls are not mandatory for part 91 operators.


As a purely Part 91 operator with an aircraft whose engines have exceeded the manufacturer’s recommended calendar TBO interval; however, may still have hundreds or potentially thousands of operating hours remaining until the manufacturer’s recommended hourly TBO interval is reached, does the statement above “…Part 91 operators are not required to comply with a manufacturer’s entire maintenance program; as such, overhauls are not mandatory for part 91 operators.” from your perspective give credence that a Part 91 operator may continue to operate the aircraft and its engines practically and legally?


This interpretation by a Part 91 operator has the potential to save that operator hundreds of thousands to well over one million dollars in engine overhaul costs, or be able to have that operator defer those overhaul costs to a future time.


If a Part 91 operator using the above interpretation uses its own internal maintenance personnel, and the decision is made by that owner to continue to operate its aircraft’s engines per the above FAA National Policy beyond the manufacturer’s recommended TBO interval, then this is straightforward; however, if that same Part 91 operator has its aircraft maintenance performed by a Part 145 repair station, could that operator be at risk by having that repair station contradict the position of the Part 91 operator, mandating overhauls are due citing only the manufacturer’s recommended engine TBO interval, and potentially not issue return to service logbook entry sign offs.


I’ve spoken with several sources including aircraft manufacturers, engine manufacturers, Part 145 repair stations, Part 91 operators and FAA FSDO personnel, and have received a broad spectrum of interpretations on this topic.  I’d be interested in learning your perspective on this issue, especially from Part 91 operators and Part 145 repair stations.


Thank you,


Verlyn Wolfe

Wolfe Aviation

(209) 983-0117 ext. 233 = Office

(209) 607-9804 = Cellular

Categories: News, US

Airtext brings cell phone convenience and other data collection to GA

Thu, 10/19/2017 - 10:22

FLYING Magazine
There are people who claim their cell phone works everywhere, even while cruising along at 10,000 feet in their Baron, or PC-12. Experts will tell you of course that while there's always the chance an airborne phone might grab a scrap or two of cell service in flight, it's never reliable enough to regularly send a text or complete a voice conversation.  READ MORE 

Categories: News, US

AEPC™ and PAMA announce the creation of a scholarship program for aircraft maintenance technicians

Mon, 10/16/2017 - 11:31

Today, AeroEngine Protection Corp (AEPC™) and the Professional Aviation Maintenance Association (PAMA) announced the formation of a scholarship program for individuals interested in a career as an aircraft maintenance technician. Aircraft maintenance technicians are the lifeline of the aviation industry as they are responsible for keeping aircraft flying by maintaining the aircraft to the safety standards mandated by the Federal Aviation Administration (FAA). As more aircraft are produced over the next several years, the need for qualified aircraft maintenance technicians will continue to grow exponentially.  READ MORE 

Categories: News, US

Air France explores blockchain potential for aircraft maintenance processes

Fri, 10/06/2017 - 10:39

Air France is exploring blockchain potential for the management of replacement parts on in-service airplanes, Aviation Today reported.

Air France KLM’s engineering and maintenance division is using its MRO Lab to experiment with the technology. The airlines uses MRO Lab to collaborate with universities, manufacturers and software developers to work on innovative ideas for the aviation industry.

James Kornberg, director of innovation of the Air France KLM business unit, said that his team is seeking to establish a clear blockchain business case for improving maintenance processes and work flows.

Read More

Categories: News, US