79-11-05 R1 MOONEY: Amendment 39-3480 as amended by Amendment 39-4050. Applies to Mooney M-18L S/N's 2 and up, M-18C S/N's 201 and up, M-18LA S/N's 100 through 200, M- 18C55 S/N's 323 and up certificated in all categories.
Compliance required as indicated:
To prevent failure of the vertical fin spar in flight due to wood deterioration and to detect other wood and glue joint deterioration in the wood wing and wood empennage structure, accomplish the following inspections and checks or approved equivalents within the next 30 days after the effective date of this AD, unless already accomplished within the last 35 months, and thereafter at intervals not to exceed 36 months from the last inspection:
(1) Remove all fabric from the horizontal and vertical stabilizers. Inspect all wood and glue joints including attachment of leading edge skin to main spar for deterioration.
(2) At center junction of stabilizer spar and fin inspect glue joint between attach blocks and stabilizer spar for deterioration and inspect spar and blocks for cracks. Inspect fin and spar for cracks at attachment bolts.
(3) Inspect rear bulkhead of the stabilizer for cracks and looseness in the area of the stabilizer attachments. Inspect attachment blocks for cracks or looseness at spar.
(4) Remove wing fabric locally in area of aileron hinges and at inboard corner of aileron cutout. Check condition of wood and glue joints. If evidence of deterioration is found, remove fabric further as necessary for complete examination of forward area of wing trailing edge. Check attachment of wing trailing edge in aileron area for looseness.
(5) Ensure that all drain holes in empennage and wing are clear.
(6) If any defects set forth in paragraphs (1), (2), (3), or (4) above are detected, repair in accordance with FAA Advisory Circular AC 43.13-1A or approved equivalent or replace with an identical new part or equivalent prior to further flight. Equivalent repairs, inspections, and/orparts must be approved by the Chief, Engineering and Manufacturing Branch, FAA, Eastern Region.
(7) A borescope, utilizing FAA approved permanent access holes, is considered an approved equivalent means of inspection only for the vertical and horizontal stabilizers, when satisfying the requirements of paragraphs (1), (2), and (3). The borescope inspection shall be accomplished within the next 30 days after the effective date of this AD, unless already accomplished within the last 11 months, and thereafter at intervals not to exceed 12 months from the last inspection.
(8) Upon submission of substantiating data by an owner or operator, through an FAA maintenance inspector, the Chief, Engineering and Manufacturing Branch, FAA, Eastern Region, may adjust the inspection time in this Airworthiness Directive.
Amendment 39-3480 was effective June 5, 1979.
This amendment 39-4050 is effective April 1, 1981.