| AD Number | 64-17-04 | Status | Active |
| Effective Date | Not specified | Issue Date | Not specified |
| Docket Number | Unknown | Amendment | N/A |
| Product Type | ["Aircraft"] | Product Subtype | ["Small Airplane"] |
| CFR Part | --- - Part 39 | CFR Section | N/A |
| Citation | Federal Register July 28, 1964 | ||
| Manufacturer(s) | American Champion Aircraft Corp. |
| Model(s) | 402 |
64-17-04 CHAMPION: Amdt. 774 Part 507 Federal Register July 28, 1964. Applies to Model 402 Aircraft.
Compliance required as indicated.
There have been instances of cracking of exhaust stack extension at the clamp which attaches it to the main exhaust manifold. This allows hot exhaust gases to discharge into the engine compartment. There have also been failures of the exhaust stack extension rear support hanger. To correct this condition, accomplish the following:
(a) Before each flight after the effective date of this AD, check by grasping and shaking for movement each exhaust stack extension to determine whether the exhaust stack extension connection to the manifold is loose or the rear support hanger has failed and make an appropriate entry in the aircraft record. The pilot may perform the check set forth in this paragraph.
(b) Repair or replace loose or failed components before further flight.
(c) Within 25 hours' time in service after the effective date of this AD, and within every 50 hours' time in service thereafter, accomplish the following:
(1) Remove the attachment clamp which attaches the exhaust stack extension to the manifold on the right and left sides of both engines and visually inspect for cracks in the joining area of the exhaust stack extension and the exhaust manifold. Also visually inspect for elongated locating pin holes and for sheared or worn clamp positioning pins.
(2) Check the edge distances of the clamp locating pin holes in the manifold. The minimum allowable edge distance is one-half inch. If the edge distance is less than one-half inch, reinstall the exhaust stack extension in accordance with the reinstallation instructions in Champion Service Letter No. 66.
(3) Visually inspect stack extension rear support hanger for failure.
(4) Replace or repair any failed or worn parts.
(d) The repetitive inspections in paragraphs (a) and (c) may be discontinued when an improvedexhaust stack extension attachment clamp and flexible rear stack hangar have been installed on right and left sides of both engines in accordance with Champion Kit No. 224.
(Champion Service Letter No. 66 and Champion Kit No. 224 cover this same subject.)
This directive effective July 28, 1964.
Revised October 15, 1964.