Alternative Inspection Procedure for AD 2011-07-13

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Commander Owners Group Alternative Inspection Procedure for AD 2011-07-13 Submitted by: Glenn Mores Commander Owners Group 21921 Oak Leaf Lane Bullard, TX 75757 gmores@microdata.com Affected models: Commander Aircraft Corporation, Gulfstream Aerospace Corporation, and Rockwell International models 112, 112B, 112TC, 112TCA, 114, 114A, 114B, 114TC. All serial numbers of all models would be covered by this AMOC. AD referenced by this AMOC: 2011-07-13 Inspection Procedure 1. Remove the attaching hardware for both outboard elevation tips per the Commander Maintenance Manual. A listing of the officially approved version of the Maintenance Manual for each model Commander aircraft may be found on the Commander Premier website at: http://www.commanderpremier.com/documents/Technical_and_Service_documentat ion_levels.pdf 2. Using a 10x magnifier, visually inspect the area immediately surrounding the outboard elevator hinge fittings attached to the elevator for any cracks or signs of smoke produced by cracks in the elevator spar web. If no cracks are noted, clean the area and re-inspect. If suspect areas are noted, clean the area and perform a Dye Penetrant Inspection (DPI) using red dye penetrant. The below guidelines provide general instructions for the use of red dye penetrant, but any red dye inspection should be in compliance with the product manufacturer’s guidelines and ASTM E165 (ASTM Standard E165, 2009, “Standard Practice for Liquid Penetrant Examination for General Industry, ASTM International, West Conshohocken, PA, 2009, DOI: 10.1520/E0165-09, www.astm.org) a. Step 1 – PRECLEANING i. Parts should be free from rust, scale, flux and other contaminants which will provide false indications. Use manufacturer’s recommended cleaner for effective pre-cleaning results. Parts and materials are to be completely dry before application of penetrant. b. Step 2 – APPLICATION OF PENETRANT i. Dye penetrants may be applied by dipping, spraying, brushing or other means which effectively covers area. After applying penetrant, position parts to allow excess to drain from surface. Refer to manufacturer’s label for minimum dwell times. c. Step 3 – REMOVAL OF PENETRANT i. After appropriate dwell time remove penetrant. For solvent based penetrants remove excess penetrant by wiping with lint free cloth. DO NOT FLUSH THE PENETRANT FROM SURFACE WITH SOLVENT. For water washable penetrants remove with steady stream of water. DO NOT FLUSH SURFACE TOO LONG OR VIGOROUSLY. d. Step 4 – APPLICATION OF NON-AQUEOUS WET DEVELOPER i. Prior to use agitate developed thoroughly. Consult manufacturer’s label for specific application instructions, but typical non-aqueous wet developer may be applied by spray or brush to surface area in a manner which provides a thin, even developer film. e. Step 5 – INSPECTION i. Sufficient dwell time is required to allow indication to form. Consult the manufacturer’s label for specific product dwell times, but the minimum dwell time for non-aqueous wet developers is TEN MINUTES. Inspection should be made before penetrant bleeds into developer (maximum dwell time SIXTY MINUTES) causing loss of definition. f. Step 6 – FINAL CLEANING i. Once areas containing flaws have been analyzed and recorded, use manufacturer recommended cleaner to remove developer and penetrant residue from surface area. Make sure all dye penetrant product materials are thoroughly removed. g. If the DPI finds any cracks or cracks are suspected, proceed to Step 4. 3. Inspect the aft face of the spar web in the area of the fitting with a flexible fiberscope/borescope which should have the following characteristics: resolution of at least 720x480 for video or 10,000 fibers for direct visual use, 6mm or smaller shaft size, focus down to 4cm, and 10x magnification. The inspection procedure varies slightly depending upon the Commander model as two different end ribs were used in production. a. Full length rib used in most early models. Insert borescope in the rear lightening hole on the outer elevator rib (see picture below). Inspection should cover the areas surrounding the four attachment nuts and extending upward and downward to the elevator skins and at least 1" inboard and outboard from the nuts. If suspect areas are noted, proceed to Step 4. If no suspect areas are noted, this completes the inspection. Proceed to Step 5 to report results. b. Shortened rib used in most later models. Insert the borescope between the aft end of the outboard elevator rib and the trailing edge of the elevator skin (see picture below). Inspection should cover the areas surrounding the four attachment nuts and extending upward and downward to the elevator skins and at least 1" inboard and outboard from the nuts. If suspect areas are noted, proceed to Step 4. If no suspect areas are noted, this completes the inspection. Proceed to Step 5 to report results. 4. If any suspect areas are found removal of the elevator for further inspection will be required and this is outlined below. a. Disconnect the elevator trim pushrod at the trim tab. b. Remove the hinge bolts at the horizontal stabilizer points. c. Remove six screws and two bolts at the inboard end of the elevator and remove the elevator. d. Remove all fasteners common to the elevator outboard aft end rib, part number (P/N) 44330, and elevator skin, P/N 44323. e. Remove the remaining two fasteners common to the elevator outboard aft End rib (P/N 44330) and the elevator spar, P/N 44211. f. Remove the elevator aft end rib, P/N 44330, to gain access to the aft side of the elevator spar. Remove the four bolts, washers, and nuts that secure the outboard elevator hinge, P/N 44285. g. Remove elevator hinge, P/N 44285, from the elevator spar. h. Clean in and around the location of the outboard bracket on the elevator spar and visually inspect for cracks. Use a 10X magnifier to facilitate the detection of any crack.