Airworthiness Directive · Amendment 39-15718 · Allied Ag Cat Productions, Inc. Model G-164 Series Airplanes
Allied Ag Cat Productions, Inc. Model G-164 Series Airplanes
Superseded. A later AD replaced this one: AD 2011-05-07. Comply with the one in force.
This AD applies to the following airplane models, all serial numbers, that are certificated in any category:
| Models |
|---|
| G-164, G-164A, G-164B, G-164B with 73” wing gap, G-164B-15T, G-164B-34T, G-164B-20T, G-164C, G-164D, and G-164D with 73” wing gap. |
The FAA adopts a new airworthiness directive (AD) to supersede AD 78-08-09, which applies to certain Allied Ag Cat Productions, Inc. (formerly Grumman-American) (Allied Ag Cat) Models G-164, G-164A, and G-164B airplanes. AD 78-08-09 currently requires repetitively inspecting the interior and the exterior of the main tubular spar of the rudder assembly for corrosion, taking necessary corrective action if corrosion is found, and applying corrosion protection. Since we issued AD 78-08-09, the rudder main tubular spar failed on a later production airplane. Consequently, this AD retains the actions required in AD 78-08-09 and expands the applicability to include all G-164 series airplanes. We are issuing this AD to detect and correct corrosion in the rudder main tubular spar, which could result in failure of the weld to the main spar tube. This failure could lead to loss of directional control.
To address this problem, you must do the following, unless already done:
| Actions | Compliance | Procedures |
|---|---|---|
| (1) Drill an access hole and do a visual inspection using a borescope of the lower end internal cavity of the rudder main spar tube for corrosion and do a visual inspection of the exterior of the rudder main spar tube for corrosion | (i) For airplanes previously affected by AD 78-08-09: Initially inspect within the next 60 months after the last inspection required in AD 78-08-09 or within the next 30 days after December 19, 2008 (the effective date of this AD), whichever occurs later. Repetitively inspect thereafter at intervals not to exceed 60 calendar months | Following Steps 1 through 3 of Grumman American Aviation Corporation Ag-Cat Service Bulletin No. 61, dated June 6, 1977. |
| (ii) For airplanes not previously affected by AD 78-08-09: Initially inspect within the next 30 days after the effective date of this AD. Repetitively inspect thereafter at intervals not to exceed 60 calendar months | ||
| (2) If corrosion is found during any inspection required in paragraph (e)(1) of this AD, repair in accordance with Advisory Circular 43.13-1B, Chg 1, dated September 27, 2001, or replace the damaged part(s) | Before further flight after any inspection in which corrosion is found | As specified in Steps 5 and 6 of Grumman American Aviation Corporation Ag-Cat Service Bulletin No. 61, dated June 6, 1977, and following Advisory Circular 43.13-1B, Chg 1, dated September 27, 2001, which can be found at http://rgl.faa.gov/. |
| (3) After each inspection, repair, or replacement required in this AD, corrosion protect the spar tube internal cavity by filling with warm, raw linseed oil, Paralketone, or CRC3 (LPS Heavy Duty Rust Inhibitor Type 3), or suitable equivalent protector for alloy steel, and allow to drain. Seal access hole with Scotch caulking compound, a suitable silicone based sealant, or equivalent | Before further flight after any inspection required in paragraph (e)(1) of this AD and after any repair or replacement required in paragraph (e)(2) of this AD | As specified in Step 4 of Grumman American Aviation Corporation Ag-Cat Service Bulletin No. 61, dated June 6, 1977. |
| (4) Verify rigging check of the rudder | Before further flight after any inspection required in paragraph (e)(1) of this AD and after any repair or replacement required in paragraph (e)(2) of this AD | (i) Following Ag-Cat Maintenance Manual pages 6-14 through 6-16, copyright 1978; or (ii) Following Ag-Cat G-164D Maintenance Manual pages 6-24 and 6-29, copyright 1995. |
| (5) Only install a rudder that has been inspected as specified in paragraph (e)(1) of this AD, is free of corrosion, and has had the corrosion protection applied and sealed as specified in paragraph (e)(3) of this AD | As of the next 30 days after December 19, 2008 (the effective date of this AD) | Not applicable. |
