| AD Number | 75-04-12 | Status | Active |
| Effective Date | February 21, 1975 | Issue Date | Not specified |
| Docket Number | Unknown | Amendment | 39-2093 |
| Product Type | ["Aircraft"] | Product Subtype | ["Small Airplane"] |
| CFR Part | --- - Part 39 | CFR Section | N/A |
| Citation | This information is not available. | ||
| Manufacturer(s) | American Champion Aircraft Corp. |
| Model(s) | 8GCBC |
75-04-12 BELLANCA: Amendment 39-2093. Applies to Model 8GCBC Airplanes, Serial Numbers 1-74 through 119-74, 120-75 through 153-75 certificated in all categories.
Compliance required within the next 10 hours time in service after the effective date of this airworthiness directive, unless already accomplished.
To prevent possible resonant vibratory conditions with McCauley Model 1A200/HFA fixed pitch propellers installed on Lycoming 0-360-C2A, or -C2E type engines, accomplish the following in accordance with Bellanca Service Letter Number 115 and Bellanca Service Kit Number 245.
(a) Remove existing markings on the tachometer instrument glass and affix Mylar decal, Bellanca P/N 1-10443. The decal is properly affixed when: a green arc extends from 500 to 1700 RPM; a yellow arc from 1700 to 2100 RPM; a green arc from 2100 RPM to 2700 RPM; and a red radial is positioned at 2700 RPM.
(b) Install Bellanca P/N 1-10437, placard "AVOID 1700-2100 DURING DESCENT", on thetachometer instrument glass below the hour meter.
(c) Accomplish Revision Number 1 to existing FAA Approved Airplane Flight Manual (AFM) in accordance with AFM revisions page.
This amendment becomes effective February 21, 1975.