Investigation Summary
On July 10, 2007, Sky King flight N332DL was preparing for a charter departure from Tunica, Mississippi, to Tulsa, Oklahoma, with an intermediate stop in Oklahoma City. Boarding had been completed, and ground personnel pushed back the portable airstairs despite the main cabin door (L1) remaining open. At the time, a severe thunderstorm was moving over the airport, producing heavy rain and gusty winds. To prevent the rain from soaking the galley and forward cabin area, a mechanic on board was directed to secure the door. According to passenger witnesses in the first row, the forward flight attendant had initially tried to close the door but stepped aside for the mechanic. As the mechanic reached for the handle, the combination of wet surfaces and high winds caused his feet to slip. Because the airstairs had already been removed, there was no platform to catch him, and he fell directly onto the concrete ramp. The mechanic was the only fatality; no damage was reported to the aircraft, and no other occupants were injured.
Final Conclusions
The National Transportation Safety Board determined the probable cause to be the ground service personnel's removal of the portable stairway prior to the main cabin door being secured. Contributing factors were the high winds and heavy rain associated with the thunderstorm.
Video Analysis
No video analysis linked for this case file yet.
Airframe & Maintenance
Crew Experience
Captain
Age 52, Male. Held an Airline Transport certificate. Last FAA medical exam March 1, 2007.
Check Pilot
Age 55, Male. Occupied the right seat. Held Airline Transport and Flight Instructor certificates. Last FAA medical exam January 1, 2007.
Systems & Failure Modes
Main Cabin Door (L1)
The primary entrance door on the forward left side of the Boeing 737, which requires manual closure and locking from the interior.
Portable Airstairs
Non-integrated ground equipment used for passenger boarding and egress when a jetbridge is not available.
Interesting Facts
- 01The aircraft was standing with engines not operating at the time of the accident.
- 02The flight was a Part 121 supplemental domestic charter flight.
- 03The mechanic, Alan Simpson, was one of six crew members on board.
- 04Ground personnel removed the external load equipment (airstairs) in an improper sequence before the door was secured.
- 05The aircraft was configured with 127 seats and was carrying 110 passengers.
- 06The mechanic sustained fatal injuries including a skull fracture and broken ribs after falling approximately 10 feet to the concrete ramp.
- 07The mechanic succumbed to his injuries the day after the accident, on July 11, 2007.
Safety Actions & Advisories
Safety Bulletin Issuance
Sky King, Inc. published a safety bulletin emphasizing the requirement to keep portable airstairs or jet-bridges in place until the main cabin door is secured.
Manual Revisions
Flight attendant and flight operations manuals were revised to include a specific caution that the L1 door must remain open with stairs in place until push-back for egress safety.
Training Emphasis
The operator implemented mandatory emphasis on portable airstair procedures during initial and recurrent training for all crew members.
Location
ACCIDENT SITE · Coordinates taken from the ntsb final report.