48-28-02: Cabin Heater Combustion Ducts
FAA order 48-28-02 is an airworthiness directive. The FAA's subject line: Cabin Heater Combustion Ducts. It names Douglas C-54: about 7 aircraft on the U.S. register today, though an order usually covers particular versions or serial numbers rather than every one. System: cabin, seats and restraints.
What it applies to as the FAA lists it
- Kind of product
- Aircraft
- Makes
- The Boeing Company
- Models
- C54-DC, C54A-DC, C54B-DC, C54D-DC, C54E-DC, C54G-DC, DC-4
- On this site
- Douglas C-54 7 registered
Dates and paperwork
- Docket
- Unknown
- Status
- Current
- The FAA's document
- Read the order on the FAA's site
The order itself the regulatory text, as published
Show the full text (337 characters)
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.)
Related safety bulletins advice on the same designs, not orders
2014-11-24NM-15-03 · Flight Controls
Source: FAA Dynamic Regulatory System, airworthiness directives. The FAA's document is the authority; the register counts are this site's, from the FAA register of November 6, 2026. Connections as data: /graph/directive/48-28-02.json · aircraft systems.