# NTSB CHI88IA061: Douglas DC-10, N123AA, Chicago, IL, February 11, 1988

- Type: NTSB incident investigation
- Classification: Incident · No injuries · Incident investigation · Final report
- Date: February 10, 1988, 22:48 local (Feb 11, 1988, 04:48 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: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 206 uninjured
- Status: Completed, report January 31, 1990
- Report: Approved by Office Director
- NTSB case key (mKey): 13985
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI88IA061
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/13985/pdf
- Page: https://openairdocs.org/ntsb/CHI88IA061

## Probable cause

JUDGEMENTAL ERROR ON THE PART OF THE LOCAL CONTROLLER FOR CLEARING VEHICLES ACROSS THE ACTIVE RUNWAY TIWH INSUFFICIENT SEPARATION FROM ARRIVING AIRCRAFT, WHICH WAS FURTHER COMPROMISED BY A MECHANICAL MALFUNCTION IN THE EQUIPMENT CROSSING THE RUNWAY.

## Sequence of events

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

- Miscellaneous/other, landing - roll
  - airport snow removal - initiated, airport personnel
  - light condition - dark night (contributing factor)
  - weather condition - snow (contributing factor)
  - atc clearance - issued
  - object - vehicle (contributing factor)
  - information - improper, driver of vehicle (cause)
  - visual/aural perception (contributing factor)

## Analysis

AT 2245:29 CST, A DC-10 FLT CREW RPRTD AT THE FINAL APCH FIX ON AN ILS RWY 9R APCH. THE FINAL APCH FIX WAS 4.7 MI FROM THE RWY. THE DC-10 WAS CLEARED TO LAND, THEN MOMENTS LATER, A SNOW REMOVAL TEAM (WORKING ON RWY 32L) REQUESTED THAT FOUR VEHICLES BE CLEARED TO CROSS RWY 9R. THE TOWER CONTROLLER PROVIDED CLEARANCE FOR THE VEHICLES TO CROSS THE ACTIVE RWY. AT 2247:28, THE LEAD MAN OF THE GROUP OF VEHICLES REPORTED THAT THEY WERE CLEAR OF THE RWY. HOWEVER, WHEN THE FOURTH VEHICLE WAS ABOUT HALF WAY ACROSS THE RWY, ITS MANUAL TRANSMISSION JUMPED OUT OF GEAR & THE DRIVER HAD DIFFICULTY REENGAGING IT. AT 2248:00, THE LEAD MAN OF THE VEHICLES NOTIFIED THE TOWER OF THE PROBLEM, BUT BY THEN, THE DC-10 WAS LANDING. AFTER THE DC-10 HAD TOUCHED DOWN & THE SPOILERS WERE DEPLOYED (BEFORE THE NOSEWHEEL WAS LOWERED),THE FLT CREW SAW THE VEHICLE AT THE EDGE OF THE RWY & THE CAPTAIN TOOK EVASIVE ACTION. HE STEARED THE ACFT AROUND THE VEHICLE, THEN CONTINUED THE LANDING WITHOUT FURTHER INCIDENT.

## Aircraft

- Registration: [N123AA](https://openairdocs.org/deregistered/N123AA-2002-06-10), registration cancelled 2002-06-10, S/N 46523, built 1972 (OpenAirDocs)
- Reported make and model: DOUGLAS DC-10
- Registry model: [Mcdonnell Douglas DC-10-10](https://openairdocs.org/model/mcdonnell-douglas-dc-10-10) (registry code 3022110) (OpenAirDocs)
- Registry engine: [GE CF6-6 series](https://openairdocs.org/engine/ge-cf6-6-series) (registry code 30020, turbo-fan) (OpenAirDocs)
- Category: Airplane
- Serial number: 46523
- Engines: GE CF6 51300 lbs thrust turbo fan
- Damage: No damage
- Flight: Part 121
- Operator: American Airlines
- Registered owner: Wilmington Trust Co., Trustee
- Airworthiness certificate: Standard, Transport
- Departed: LAX, LOS ANGELES, CA
- Flight plan: IFR
- Airport: ORD, Chicago O'Hare, runway 9R, 10,140 × 150 ft, concrete

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 46; airline transport, flight engineer; airplane ratings: multi-engine land; instrument ratings: airplane; medical: class 1, valid medical--no waivers/lim.; seat: left; flight hours: 14,446 total

## Weather

- Conditions: Instrument (IMC), Night/dark
- Wind: 90° at 15 knots
- Visibility: 1 statute miles
- Lowest ceiling: 700 ft overcast
- Temperature: 19 °F, dew point 19 °F
- Altimeter: 30.00 inHg
- Observed at: ORD, 1 nm away

## Other investigations on N123AA (1)

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.

- [NTSB NYC84IA007](https://openairdocs.org/ntsb/NYC84IA007), Oct 12, 1983: McDonnell Douglas DC-10-10 (N123AA), Atlantic Ocean (Atlantic Ocean), incident, no damage

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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