# NTSB CHI86MA142: Mcdonnell Douglas DC-9-31, N973VJ, Chicago, IL, May 17, 1986

- Type: NTSB incident investigation
- Classification: Incident · No injuries · Major investigation · Final report
- Date: May 17, 1986, 09:59 local (14:59 UTC)
- Place: Chicago, IL
- Location: 41.9769° N, 87.9081° W: Placed by OpenAirDocs at CHICAGO O'HARE INTL (ORD), within about a mile (OpenAirDocs)
- Nearby events: https://openairdocs.org/map.md?lat=41.9769&lon=-87.9081&mi=10
- Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 224 uninjured
- Status: Completed
- Report: Approved by Office Director
- Safety recommendations: Yes
- NTSB case key (mKey): 13538
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI86MA142
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/13538/pdf
- Page: https://openairdocs.org/ntsb/CHI86MA142

## Sequence of events

In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf).

- Near collision between aircraft, takeoff - roll/run
  - ifr separation standards - not followed, atc personnel(lcl/gnd/clnc) (cause)
  - excessive workload (task overload), atc personnel(lcl/gnd/clnc) (contributing factor)
  - supervision - inadequate, atc personnel(supervisor) (contributing factor)
  - excessive workload (task overload), atc personnel(supervisor) (contributing factor)
- Near collision between aircraft, takeoff - roll/run
  - atc clearance - inadvertent, atc personnel(lcl/gnd/clnc) (cause)
  - excessive workload (task overload), atc personnel(lcl/gnd/clnc) (contributing factor)
  - supervision - inadequate, atc personnel(supervisor) (contributing factor)
  - excessive workload (task overload), atc personnel(supervisor) (contributing factor)

## Analysis (aircraft 2)

U.S. AIR FLIGHT 373 PASSED OVER AMERICAN AIRLINES FLIGHT 695 AT THE INTERSECTION OF RUNWAYS 32R AND 4L WHILE BOTH AIRCRAFT WERE TAKING OFF. BOTH AIRCRAFT HAD BEEN CLEARED FOR TAKEOFF BY THE LOCAL CONTROLLER AT O'HARE TOWER. THE AIRCRAFT CAME WITHIN TWENTY FEET OF EACH OTHER DURING THE OCCURRENCE. THE LOCAL CONTROLLER WAS INVOLVED IN GIVING ADDITIONAL SEVERE WEATHER AVOIDANCE (SWAP) CLEARANCES WHEN HE INADVERTENTLY FORGOT HE HAD CLEARED THE U.S. AIR FLIGHT FOR TAKEOFF AND THEN ABOUT 20 SECONDS LATER CLEARED THE AMERICAN FLIGHT FOR TAKEOFF.

## Analysis (aircraft 1)

U.S. AIR FLIGHT 373 PASSED OVER AMERICAN AIRLINES FLIGHT 695AT THE INTERSECTION OF RUNWAYS 32R AND 4L WHILE BOTH AIRCRAFT WERE TAKING OFF. BOTH AIRCRAFT HAD BEEN CLEARED FOR TAKEOFF BY THE LOCAL CONTROLLER AT O'HARE TOWER. THE AIRCRAFT CAME WITHIN TWENTY FEET OF EACH OTHER DURING THE OCCURRENCE. THE LOCAL CONTROLLER WAS INVOLVED IN GIVING ADDITIONAL SEVERE WEATHER AVOIDANCE (SWAP) CLEARANCES WHEN HE INADVERTENTLY FORGOT HE HAD CLEARED THE U.S. AIR FLIGHT FOR TAKEOFF AND THEN ABOUT 20 SECONDS LATER CLEARED THE AMERICAN FLIGHT FOR TAKEOFF.

## Aircraft 1

- Registration: [N973VJ](https://openairdocs.org/deregistered/N973VJ-2003-07-17), registration cancelled 2003-07-17, S/N 47099, built 1967 (OpenAirDocs)
- Reported make and model: MCDONNELL DOUGLAS DC-9-31
- Registry model: [Douglas DC-9-31](https://openairdocs.org/model/douglas-dc-9-31) (registry code 3022065) (OpenAirDocs)
- Registry engine: [Pratt & Whitney JT8D-9 series](https://openairdocs.org/engine/pratt-whitney-jt8d-9-series) (registry code 52048, turbo-jet) (OpenAirDocs)
- Category: Airplane
- Engines: P&W JT-9D 14500 lbs thrust turbo fan
- Damage: Minor damage
- Flight: Part 121
- Registered owner: Usair
- Airworthiness certificate: Standard, Transport
- Departed: ORD, CHICAGO, IL
- Destination: PIT, PITTSBURGH, PA
- Flight plan: IFR
- Airport: ORD, O'Hare, runway 4L, 7,500 × 150 ft, concrete

## Aircraft 2

- Registration: [N6833](https://openairdocs.org/deregistered/N6833-2011-09-22), registration cancelled 2011-09-22, S/N 20186, built 1969 (OpenAirDocs)
- Reported make and model: BOEING 727-223
- Registry model: [Boeing 727-223](https://openairdocs.org/model/boeing-727-223) (registry code 1384074) (OpenAirDocs)
- Registry engine: [Pratt & Whitney JT8D-9 series](https://openairdocs.org/engine/pratt-whitney-jt8d-9-series) (registry code 52048, turbo-jet) (OpenAirDocs)
- Category: Airplane
- Engines: P&W JT-9D 14500 lbs thrust turbo fan
- Damage: No damage
- Flight: Part 121
- Registered owner: American Airlines
- Airworthiness certificate: Standard, Transport
- Destination: OKC, OKLAHOMA CITY, OK
- Flight plan: IFR
- Airport: ORD, O'Hare, runway 32R, 10,003 × 150 ft, concrete

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot, aircraft N973VJ; airline transport; airplane ratings: multi-engine land; instrument ratings: airplane; medical: class 1, valid medical--no waivers/lim.; seat: left
- Pilot, aircraft N6833; airline transport; airplane ratings: multi-engine land; instrument ratings: airplane; medical: class 1, valid medical--no waivers/lim.; seat: left

## Weather

- Conditions: Visual (VMC), Day
- Visibility: 5 statute miles
- Lowest ceiling: 2,000 ft broken
- Altimeter: 29.00 inHg
- Observed at: ORD

From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model.

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