- Date
- July 6, 1996, 14:24 local (19:24 UTC)
- Place
- Pensacola, FL
- Injuries
- 2 fatal, 2 serious, 3 minor, 137 uninjured
- Damage
- Substantial damage
- Phase of flight
- Takeoff
- Aircraft
- N927DAMcDonnell Douglas MD-88
- Weather
- Visual (VMC) · Day
- Status
- Completed · report March 31, 1998
- Report
- Board-adopted at Board Meeting
- Investigation class
- Class 1
- NTSB office
- Major Investigations Division
- Safety recommendations
- Yes
- FAA report
- 19960706016239A
- Case key
- 11010
From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the accident.
On this page
Probable cause
the fracture of the left engine's front compressor fan hub, which resulted from the failure of Delta Air Lines' fluorescent penetrant inspection process to detect a detectable fatigue crack initiating from an area of altered microstructure that was created during the drilling process by Volvo for Pratt & Whitney and that went undetected at the time of manufacture. Contributing to the accident was the lack of sufficient redundancy in the in-service inspection program. (NTSB Report AAR-98/01)
Sequence of events
NTSB’s coding before 2008: each occurrence and phase of flight, and the causes and factors under it. The codes are defined in NTSB’s coding manual.
Analysis
During the initial part of its takeoff roll, the airplane experienced an engine failure. Uncontained engine debris from the front compressor front hub (fan hub) of the #1 (left) engine penetrated the left aft fuselage. Two passengers were killed and two others were seriously injured. The takeoff was rejected, and the airplane was stopped on the runway. The fan hub had fractured through a tierod hole and blade slot. Some form of drill breakage or drill breakdown, combined with localized loss of coolant and chip packing, had occurred during the drilling process, creating an altered microstructure and ladder cracking in the fan hub. Drilling damage extended much deeper into hole sidewall material than previously anticipated by P & W. Fatigue cracks initiated from the ladder cracking in the tierod hole and began propagating almost immediately after the hub was put into service in 1990. The crack was large enough to have been detectable during the last fluorescent penetrant inspection at Delta. Delta's nondetection of the crack was caused either by a failure of the cleaning and fluorescent penetrant inspection processing, a failure of the inspector to detect the crack, or some combination of these factors.
Factual narrative
On July 6, 1996, Delta Airlines flight 1288, an MD-88, N927DA, experienced an uncontained failure of the left engine during the beginning of the takeoff roll. The flightcrew stopped the airplane about 1400 feet down the takeoff runway. On board the airplane were 137 passengers, 2 flightcrew members, 3 cabincrew, and 2 non-revenue Delta employees occupying the cockpit and aft jumpseats. Engine parts entered the left side of the aft cabin resulting in 2 passengers sustaining fatal injuries and 2 sustained major injuries. Three other passengers received minor injuries during the evacuation. The captain stopped the evacuation from the emergency exits, and an airstair was brought to the airplane to evacuate the remaining passengers and the crew. The fan hub for the left engine was found fractured.
Aircraft
- Registration
- N927DA
- Reported as
- McDonnell Douglas MD-88
- Category
- Airplane
- Serial number
- 49714
- Airframe hours
- 22,031
- Engine
- P&W JT8D-219, 21,000 lbs thrust, turbo jet
- Damage
- Substantial damage
- Fire
- On-Ground
- Flight
- Part 121
- Registered owner
- Delta Air Lines Inc
- Airworthiness certificate
- Standard, Transport
- Departed
- PNS
- Destination
- ATL · Atlanta, GA
- Flight plan
- IFR
- Airport
- PNS · Pensacola Regional, runway 17, 7,002 × 150 ft, asphalt
Matched to the registry by N-number and the event date; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.
Flight crew · 2
As NTSB recorded them. NTSB leaves out names.
- Role
- Pilot
- Age
- 40
- Certificate
- Airline transport
- Airplane ratings
- Multi-engine land
- Instrument ratings
- Airplane
- Medical
- Class 1, Valid Medical--w/ waivers/lim
- Seat
- Left
- Toxicology
- Performed
- Flight hours
- 12,000 total · 2,300 in this make and model · 142 in the last 90 days · 39 in the last 30 days
- Role
- Co-pilot
- Age
- 37
- Certificate
- Airline transport
- Airplane ratings
- Single-engine land, Multi-engine land
- Instrument ratings
- Airplane
- Medical
- Class 1, Without waivers/limitations
- Seat
- Right
- Toxicology
- Performed
Weather
- Conditions
- Visual (VMC) · Day
- Wind
- 210° at 12 knots
- Visibility
- 7 statute miles
- Temperature
- 90 °F, dew point 77 °F
- Altimeter
- 29.00 inHg
- Observed at
- PNS
Docket · 183
The files NTSB released with the investigation on March 25, 1997, on NTSB’s docket system: statements, records, photos and specialists’ reports. 94.6 MB in all.
FAA reports on this event · 1
The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.