- Date
- March 23, 1987, 09:58 local (15:58 UTC)
- Place
- Minneapolis, MN
- Injuries
- 114 uninjured
- Damage
- Minor damage
- Phase of flight
- Enroute
- Aircraft
- N409AAMcdonnell Douglas DC-9-82
- Weather
- Day
- Status
- Completed · report July 10, 1989
- Report
- Approved by Office Director
- Safety recommendations
- Yes
- Case key
- 13664
From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the incident.
On this page
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
The aircraft landed uneventfully after the right engine failed during a descent. The shutdown occurred after failed antirotation pins allowed gas loads to drive normally stationary third stage vane clusters in the low pressure turbine area. Rotation of the clusters in their channel allowed the clusters to machine themselves out through the low pressure turbine case. Evidence indicates that 23 of the 44 third stage vane anti-rotation pins ruptured followed by fracture of the remaining pins from shear overload. The pin stress rupture was the result of bending stresses on the vane pins from vane twist & pin material creep. A design task was initiated in 1986 to provide a more durable pin and in may 1987 p&w released a new material, inco 901 non-stepped, anti-rotation pin, pn 803995, to replace the pn 599714 tinidur pin.
Aircraft
- Registration
- N409AA
- Reported as
- Mcdonnell Douglas DC-9-82
- Category
- Airplane
- Serial number
- 49320
- Engine
- P&W JT8D-217, 20,550 lbs thrust, turbo fan
- Damage
- Minor damage
- Flight
- Part 121
- Registered owner
- American Airlines Inc.
- Airworthiness certificate
- Standard, Transport
- Departed
- ORD · Chicago, IL
- Destination
- MSP · Minneapolis, MN
- Flight plan
- IFR
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
As NTSB recorded them. NTSB leaves out names.
- Role
- Pilot
- Age
- 43
- Certificates
- Airline transport, Flight instructor
- Airplane ratings
- Multi-engine land, Single-engine land
- Instrument ratings
- Airplane
- Medical
- Class 1, Valid Medical--no waivers/lim.
- Seat
- Left
- Flight hours
- 7,000 total · 180 in the last 90 days
Weather
- Conditions
- Day
- Wind
- 130° at 13 knots
- Visibility
- 8 statute miles
- Lowest ceiling
- 4,600 ft overcast
- Temperature
- 46 °F, dew point 43 °F
- Altimeter
- 29.00 inHg
- Observed at
- MSP, 30 nm away