Investigation Summary
FedEx Flight 1406 was a scheduled cargo flight from Memphis to Boston. Approximately two hours into the flight, while cruising at FL330, the Cabin Smoke Fire Alarm sounded, initially indicating smoke in cargo zones 7, 8, and 9. The crew donned oxygen masks and initiated a high-speed emergency descent with full speed brakes. During the descent, additional smoke detectors triggered, and the crew reported smoke entering the cockpit, which significantly reduced visibility. ATC provided options for landing at Albany or Stewart; the crew chose Stewart International Airport due to its proximity. Upon landing on Runway 27, the crew taxied the aircraft off the runway but encountered difficulty during evacuation because the fuselage remained pressurized, preventing the doors and cockpit windows from opening. Once the captain manually depressurized the aircraft, the three flight crew members evacuated through a cockpit window using a rope, while the two jumpseat passengers used a forward cabin door and slide. Firefighters were unable to reach the seat of the fire due to the dense cargo configuration. Forty minutes after landing, the fire breached the fuselage skin, and the aircraft was eventually consumed by the blaze.
Final Conclusions
The National Transportation Safety Board (NTSB) released its final report (NTSB/AAR-98-03) on July 22, 1998. The investigation concluded that the probable cause of the accident was an in-flight cargo fire of undetermined origin. Despite extensive examination of the wreckage, the degree of fire damage was so severe that investigators could not identify the specific source of ignition or the material that first ignited.
Video Analysis
No video analysis linked for this case file yet.
Airframe & Maintenance
Crew Experience
Captain
Age 47
First Officer
Age 41
Flight Engineer
Age 45
Systems & Failure Modes
Cargo Smoke Detection System
A series of detectors in the main deck cargo compartment that alerted the crew to smoke in multiple zones (7, 8, 9, 6, and 10).
Cabin Pressurization System
The system maintained internal pressure which initially prevented the crew from opening emergency exits until the captain manually depressurized the vessel.
Interesting Facts
- 01The aircraft was a McDonnell Douglas DC-10-10CF manufactured in 1975.
- 02All five occupants survived, with only two crew members sustaining minor injuries.
- 03The fire was so intense that it caused the aft fuselage structure to weaken and the tail section to separate.
- 04The aircraft was named 'Chandra Renee'.
- 05The NTSB was unable to determine the exact source of ignition due to extensive fire damage.
Safety Actions & Advisories
Cargo Compartment Fire Suppression
Source ↗The NTSB issued recommendations regarding the improvement of fire detection and suppression systems in Class E cargo compartments to prevent similar total hull losses.
Hazardous Materials Oversight
Source ↗The investigation highlighted concerns regarding undeclared hazardous materials in transportation and the need for better dissemination of hazmat information to flight crews and emergency responders.
Emergency Response and Firefighting
Source ↗The NTSB evaluated the adequacy of airport emergency response and aircraft interior firefighting methods, noting that dense cargo configurations can prevent firefighters from reaching the seat of a fire.
Known Controversies & Unanswered Questions
Undetermined Origin of Fire
Reference ↗Despite an extensive investigation and the recovery of the wreckage, the NTSB was unable to identify the specific source of ignition or the material that first ignited due to the extreme severity of the fire damage, leaving the cause officially 'undetermined'.