Jeredp wrote:
Part 21
Major alteration. An alteration not listed in the aircraft, aircraft engine, or propeller specifications—
(1) That might appreciably affect weight, balance, structural strength, performance, powerplant operation, flight characteristics, or other qualities affecting airworthiness; or
7 lbs is appreciable in mind, depending on the batteries location. The FAA actualy published a document in 2001 trying to clarify major/minor. The short of it is that they intentionally used the word appreciable to leave the approval up to the discression of the inspector: http://www.faa.gov/regulations_policies ... 010594.pdf
The very document you linked explains that weight means a change in certificated weight (Page 53). That is also the intent of Appendix A, to clarify the meaning of a major alteration. So again, an increase or decrease in the empty weight has no effect, appreciably or otherwise, on the (certificated) weight.
