90-02-17 BELLANCA, INCORPORATED: Amendment 39-6446. \n\n\tApplicability: Models 14-19-3, 14-19-3A, 17-30, 17-31 and 17-31TC (all serial numbers (S/N)), 17-30A (S/N 30263 through 89-301007), 17-31A (S/N 32-15 through 78-32-172) and 17-31ATC (S/N 31004 through 79-31155) airplanes certificated in any category. \n\n\tCompliance: Required as indicated in the body of the AD, unless already accomplished. \n\n\tTo prevent the collapse of the main landing gear which could result in substantial airframe damage, accomplish the following: \n\n\t(a)\tUpon the accumulation of 500 hours total time-in-service (TIS), or within the next 100 hours TIS after the effective date of this AD, whichever occurs later, and each 100 hours TIS thereafter, inspect the left and right drag strut landing gear fitting assemblies, Part Number (P/N) 194153-10, for cracks, deformations, or failures as follows: \n\n\tNOTE 1: This information is also contained in Bellanca Service Letter B-106, dated September 26, 1989. Penetrant inspection techniques are described in FAA Advisory Circular (AC) 43-3, "Nondestructive Testing in Aircraft." These inspections can be conducted with the fitting assemblies installed on the airplane. Do not apply loads to the landing gear components, particularly the drag strut, as it is possible to move the drag strut to overcenter and cause the landing gear to collapse. \n\n\t\t(1)\tPlace jacks or other workstands under the airplane at locations specified in the Bellanca Service Manual to prevent accidental landing gear collapse during this inspection. \n\n\t\t(2)\tFigure 1 to this AD describes the 194153-10 fitting assembly. Clean the aft face of the -1 fitting with Stoddart solvent and a brush. \n\n\t\t(3)\tInspect for cracks adjacent to the welds which join the -1 fitting to the -2 fitting and -3 brace near the lower aft attachment bolt holes using liquid penetrant inspection techniques and a magnifying glass. If any crack is found, prior to further flight replace the assembly with a new fitting assembly, P/N 194153-30 or P/N 194153-40, as applicable. \n\n\t\t(4)\tLay a straight-edge along side the lower aft attachment bolts, in accordance with Figure 2 and, using a feeler gage or wire gage of .030 inch thickness, look for any evidence of local deformation (dimpling) in the -1 fitting. If any deformation greater than .030 inches is found, prior to further flight replace the assembly with a new fitting assembly, P/N 194153-30 or P/N 194153-40, as applicable. \n\n\tNOTE 2: The -30, -40 assemblies can be distinguished from a -10 assembly by measuring the -1, -2, fitting and -3 brace part thickness: -10 part thickness is 0.062 inches, -30, -40 parts thickness is 0.100 inches. A 0.040 Shim (P/N 194167-2 Shim Spar Bracket) is available to provide proper fit between the 194153 fitting assembly and the forward spar. \n\n\t\t(5)\tCheck and adjust, as required, the drag strut for correct overcenter using the appropriate procedures in the Bellanca Service Manual. \n\n\t\t(6)If the inspections specified above do not indicate any evidence of cracks or local deformation in the -1 fitting, apply zinc chromate or Epibond primer, as necessary, to protect the part and repeat these inspections as specified above. \n\n\t\t(7)\tThe repetitive inspections specified above are not required on the P/N 194153-30 or P/N 194153-40 assemblies. \n\n\t(b)\tAirplanes with cracked or deformed fittings may be flown with a special flight permit in accordance with FAR 21.197 to a location where this AD may be accomplished providing that no crack is found during the inspection of paragraph (a)(3) that exceeds 3/8 in. length, or no deformation is found during the inspection of paragraph (a)(4) that is great enough to cause the overcenter of the drag strut to be out of tolerance. In these cases, no special flight permit is allowed. \n\n\t(c)\tAn alternate method of compliance or adjustment of the initial and repetitive compliance times, which provides an equivalent level of safety, may be approved by the Manager, Chicago Aircraft Certification Office, 2300 E. Devon Avenue, Des Plaines, Illinois 60018. \n\n\tNOTE 3: The request should be forwarded through an FAA Maintenance Inspector, who may add comments and send it to the Manager, Chicago Aircraft Certification Office. \n\n\tAll persons affected by this directive may obtain copies of the documents referred to herein upon request to Bellanca, Inc.; P.O. Box 964, Alexandria, Minnesota 56308; Telephone (612) 762-1501; or may examine these documents at the FAA, Central Region, Office of the Assistant Chief Counsel, Room 1558, 601 E. 12th Street, Kansas City, Missouri 64106. \n\n\tThis amendment (39-6446, AD 90-02-17) becomes effective on February 5, 1990. \n\n\nFIGURE 1\n\n\n\nAD 90-02-17\n\nFIGURE 2\n\nEXAMPLES OF MEASURING DEPTH OF DIMPLED AREAS