Narrative:

While performing an annual inspection in conjunction with company Y, a local restoration shop, I was involved in inspecting wings and fuselage (which were damaged in a previous accident), after company Y had restored the damaged great lakes 2D-1A-2. Technician Y of company Y had performed work and signed off the 100 hour inspection. I had inspected the aircraft and signed off the annual inspection. Upon the owner testing and flying the aircraft, first the magnetos showed a rough RPM drop. The engine was rebuilt during restoration by company Z. They brought their mechanic to check the problem in the fuel injection system. Their recommendation was to lean out the engine prior to magneto check, which made the RPM drop smooth and even. This is contradictory to all my training. The normal procedure on magneto check is to leave the mixture in full rich. Second, owner complained of tailwheel shimmy, which was not addressed by company Y. I felt that these sits needed to be rectified by company Y and was told by technician Y that as far as they were concerned, these problems were addressed and fixed. In the future, to prevent this type of scenario, I wold not allow signoff of aircraft until flight testing is performed to rectify any problems.

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Original NASA ASRS Text

Title: A GREAT LAKES BIPLANE 2D-1A-2 OUT OF ANNUAL AND 100 HR INSPECTION ON TEST FLT HAS ROUGH RPM DROP ON MAGNETO CHK AND TAILWHEEL SHIMMY.

Narrative: WHILE PERFORMING AN ANNUAL INSPECTION IN CONJUNCTION WITH COMPANY Y, A LCL RESTORATION SHOP, I WAS INVOLVED IN INSPECTING WINGS AND FUSELAGE (WHICH WERE DAMAGED IN A PREVIOUS ACCIDENT), AFTER COMPANY Y HAD RESTORED THE DAMAGED GREAT LAKES 2D-1A-2. TECHNICIAN Y OF COMPANY Y HAD PERFORMED WORK AND SIGNED OFF THE 100 HR INSPECTION. I HAD INSPECTED THE ACFT AND SIGNED OFF THE ANNUAL INSPECTION. UPON THE OWNER TESTING AND FLYING THE ACFT, FIRST THE MAGNETOS SHOWED A ROUGH RPM DROP. THE ENG WAS REBUILT DURING RESTORATION BY COMPANY Z. THEY BROUGHT THEIR MECH TO CHK THE PROB IN THE FUEL INJECTION SYS. THEIR RECOMMENDATION WAS TO LEAN OUT THE ENG PRIOR TO MAGNETO CHK, WHICH MADE THE RPM DROP SMOOTH AND EVEN. THIS IS CONTRADICTORY TO ALL MY TRAINING. THE NORMAL PROC ON MAGNETO CHK IS TO LEAVE THE MIXTURE IN FULL RICH. SECOND, OWNER COMPLAINED OF TAILWHEEL SHIMMY, WHICH WAS NOT ADDRESSED BY COMPANY Y. I FELT THAT THESE SITS NEEDED TO BE RECTIFIED BY COMPANY Y AND WAS TOLD BY TECHNICIAN Y THAT AS FAR AS THEY WERE CONCERNED, THESE PROBS WERE ADDRESSED AND FIXED. IN THE FUTURE, TO PREVENT THIS TYPE OF SCENARIO, I WOLD NOT ALLOW SIGNOFF OF ACFT UNTIL FLT TESTING IS PERFORMED TO RECTIFY ANY PROBS.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.