| AD Number | 48-28-02 | Status | Active |
| Effective Date | Not specified | Issue Date | Not specified |
| Docket Number | Unknown | Amendment | N/A |
| Product Type | ["Aircraft"] | Product Subtype | ["Large Airplane"] |
| CFR Part | --- - Part 39 | CFR Section | N/A |
| Citation | This information is not available. | ||
| Manufacturer(s) | The Boeing Company |
| Model(s) | C54-DC C54A-DC C54B-DC C54D-DC C54E-DC C54G-DC DC-4 |
48-28-02 DOUGLAS: Applies to C-54 and DC-4 Aircraft. \n\n\tTo be accomplished not later than April 1, 1949. \n\n\tAs a fire protection measure in order to prevent burn through, replace the present cabin heater combustion ducts with corrosion resistant steel ducts. \n\n\t(Douglas Service Bulletin DC-4 No. 89 covers this same subject.)