- Date
- December 23, 1991, 09:05 local (15:05 UTC)
- Place
- Chicago, IL
- Injuries
- 315 uninjured
- Phase of flight
- Takeoff
- Weather
- Visual (VMC) · Day
- Status
- Completed · report May 5, 1993
- Report
- Approved by Office Director
- Case key
- 15320
From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the incident.
On this page
Probable cause
The local controller's not understanding read back of radio communications. Factors include the pilot-in-command of flight 73 not understanding verbal instructions; local controller not visually identifying the aircraft; and inadequate surveillance (FAA) in the tower.
The local controller's not understanding read back of radio communications. Factors include the pilot-in-command of flight 73 not understanding verbal instructions; local controller not visually identifying the aircraft; and inadequate surveillance (FAA) in the tower.
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
American airlines flight 73 (N142AA) was holding in position on runway 32R. American airlines flight 489 (N497AA) was cleared for takeoff on runway 9L. Shortly after this, American airlines flight 873 was cleared for takeoff on runway 32L, from T1 intersection. Both flight 73 and flight 873 acknowledged the clearance and initiated takeoff rolls. The local controller did not detect the confusion. A near collision of two of the aircraft occurred when flight 489, in initial climb phase of flight, passed over flight 73, on takeoff roll, in the intersection of runways 32R and 9L.
American airlines flight 73 (N142AA) was holding in position on runway 32R. American airlines flight 489 (N497AA) was cleared for takeoff on runway 9L. Shortly after this, American airlines flight 873 was cleared for takeoff on runway 32L, from T1 intersection. Both flight 73 and flight 873 acknowledged the clearance and initiated takeoff rolls. The local controller did not detect the confusion. A near collision of two of the aircraft occurred when flight 489, in the initial climb phase of flight, passed over flight 73, on takeoff roll, in the intersection of runways 32R and 9L.
Aircraft · 2
- Registration
- N142AA
- Reported as
- Mcdonnell Douglas DC-10-30
- Category
- Airplane
- Serial number
- 46714
- Airframe hours
- 65,122
- Engine
- GE CF6-50C2, turbo fan
- Damage
- No damage
- Flight
- Part 121
- Operator
- American Airlines, doing business as American Airlines
- Registered owner
- American Airlines
- Airworthiness certificate
- Standard, Transport
- Last inspection
- AAIP · January 2, 2000
- Destination
- HNL · Honolulu, HI
- Flight plan
- IFR
- Airport
- ORD · Chicago O'Hare, runway 32, 10,003 × 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.
- Registration
- N497AA
- Reported as
- Mcdonnell Douglas DC-9-82
- Category
- Airplane
- Serial number
- 49735
- Airframe hours
- 6,624
- Engine
- P&W JT8D-217, 20,000 lbs thrust, turbo fan
- Damage
- No damage
- Flight
- Part 121
- Operator
- American Airlines, doing business as American Airlines
- Registered owner
- Wilmington Trust Company
- Airworthiness certificate
- Standard, Transport
- Last inspection
- AAIP · January 2, 2000
- Destination
- IAH · Houston, TX
- Flight plan
- IFR
- Airport
- ORD · Chicago O'Hare, runway 9, 7,966 × 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, aircraft N142AA
- Age
- 54
- Certificate
- Airline transport
- Airplane ratings
- Multi-engine land
- Instrument ratings
- Airplane
- Medical
- Class 1, Valid Medical--no waivers/lim.
- Seat
- Left
- Flight hours
- 21,565 total · 720 in this make and model · 216 in the last 90 days · 72 in the last 30 days
- Role
- Pilot, aircraft N497AA
- Age
- 59
- Certificate
- Airline transport
- Airplane ratings
- Multi-engine land
- Instrument ratings
- Airplane
- Medical
- Class 1, Valid Medical--w/ waivers/lim
- Seat
- Left
- Flight hours
- 10,000 total · 3,623 in this make and model · 200 in the last 90 days · 75 in the last 30 days · 5 in the last 24 hours
Weather
- Conditions
- Visual (VMC) · Day
- Wind
- 40° at 9 knots
- Visibility
- 7 statute miles
- Lowest ceiling
- 2,000 ft broken
- Temperature
- 34 °F, dew point 30 °F
- Altimeter
- 29.00 inHg
- Observed at
- ORD, 1 nm away
Other investigations on N142AA · 1
Matched to the same aircraft by N-number and date.