Avidyne Corporation

AD 2008-06-28 R1 and the AD proposed under this docket, which would supersede it, identify test and repair procedures contained in Avidyne Service Bulletin No. 601-00006-096 Rev 01 as an acceptable means of compliance. They also identify this Service Bulletin as the authoritative source of applicability information, in the form of a list of serial numbers of affected Primary Flight Displays. Avidyne has updated this Service Bulletin, reissuing it as Rev 02. The test and repair requirements remain unchanged, but the list of serial numbers has been updated to remove those PFDs known to have been serviced under the SB since Rev 01 was published. These PFDs, if examined in accordance with the newly proposed AD, would be found to comply under the provisions of paragraph (f)(2) and would require no further action. Accordingly, Avidyne proposes that the new AD be modified to reference our Service Bulletin No. 601-00006-096 Rev 02 rather than Rev 01. For those PFDs that have already been serviced, this modification would eliminate redundant compliance procedures that, under the AD, may be performed only by a qualified service facility, reducing inconvenience and cost to affected operators with no adverse safety effect.