# NTSB CHI88IA073: Boeing 747-227B, N635US, Chicago, IL, February 19, 1988 - Type: NTSB incident investigation - Classification: Incident · No injuries · Incident investigation · Final report - Date: February 19, 1988, 12:07 local (18:07 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: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 297 uninjured - Status: Completed, report June 18, 1990 - Report: Approved by Office Director - NTSB case key (mKey): 13986 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI88IA073 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/13986/pdf - Page: https://openairdocs.org/ntsb/CHI88IA073 ## Probable cause (aircraft 2) FAILURE OF THE TOWER CAB SUPERVISOR TO ASSURE THAT COORDINATION BETWEEN THE SOUTH LOCAL CONTROLLER AND NORTH LOCAL CONTROLLER HAD BEEN COMPLETED. A FACTOR IS THE FAILURE OF FAA TOWER MANAGEMENT TO INSURE THERE WERE PERSONNEL MANNING THE CAB COORDINATOR POSITION. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Near collision between aircraft, takeoff - initial climb - control tower service - inadequate (cause) - crew/group coordination - inadequate, atc personnel(supervisor) (cause) - inadequate surveillance,insufficient staff, faa(organization) - Near collision between aircraft, takeoff - initial climb - control tower service - inadequate (cause) - crew/group coordination - inadequate, atc personnel(supervisor) (cause) - inadequate surveillance,insufficient staff, faa(organization) ## Analysis (aircraft 2) NORTHWEST FLT 3 (BOEING 747, N635US) WAS CLRD TO TAKEOFF ON RWY 14R AT THE SAME TIME AIR WISCONSIN FLT 925 (BAE 146, N602AW) WAS CLRD TO TAKEOFF ON RWY 22L AT THE CHICAGO-O'HARE INTL ARPT. SUBSEQUENTLY, THE TWO ACFT PASSED WITH AN ESTIMATED 3000 TO 4000 FT SEPARATION. THIS OCCURRED AFTER THE TOWER SUPERVISOR HAD NOT ASSURED COORDINATION BETWEEN THE NORTH & SOUTH LOCAL CONTROL POSITIONS. AT THE TIME OF THE OPERATIONAL ERROR, THE TOWER SUPERVISOR WAS ACTING AS BOTH THE SUPERVISOR & THE TOWER CAB COORDINATOR. ## Analysis (aircraft 1) NORTHWEST FLT 3 (BOEING 747, N635US) WAS CLRD TO TAKEOFF ON RWY 14R AT THE SAME TIME AIR WISCONSIN FLT 925 (BAE 146, N602AW) WAS CLRD TO TAKEOFF ON RWY 22L AT THE CHICAGO-O'HARE INTL ARPT. SUBSEQUENTLY, THE TWO ACFT PASSED WITH AN ESTIMATED 3000 TO 4000 FT SEPARATION. THIS OCCURRED AFTER THE TOWER SUPERVISOR HAD NOT ASSURED COORDINATION BETWEEN THE NORTH & SOUTH LOCAL CONTROL POSITIONS. AT THE TIME OF THE OPERATIONAL ERROR, THE TOWER SUPERVISOR WAS ACTING AS BOTH THE SUPERVISOR & THE TOWER CAB COORDINATOR. ## Aircraft 1 - Registration: [N635US](https://openairdocs.org/deregistered/N635US-2007-09-26), registration cancelled 2007-09-26, S/N 21682, built 1979 (OpenAirDocs) - Reported make and model: BOEING 747-227B - Registry model: [Boeing 747-227B](https://openairdocs.org/model/boeing-747-227b) (registry code 1384888) (OpenAirDocs) - Registry engine: [Pratt & Whitney JT9D-3A](https://openairdocs.org/engine/pratt-whitney-jt9d-3a) (registry code 52050, turbo-fan) (OpenAirDocs) - Category: Airplane - Serial number: 21682 - Engines: P&W JT9D 54750 lbs thrust turbo fan - Damage: No damage - Flight: Part 121 - Registered owner: Northwest Airlines - Airworthiness certificate: Standard, Transport - Destination: TOKYO, JAPAN - Flight plan: IFR - Airport: ORD, Chicago-O'Hare Intl, runway 14R, 13,000 × 200 ft, concrete ## Aircraft 2 - Registration: [N602AW](https://openairdocs.org/deregistered/N602AW-1990-06-15), registration cancelled 1990-06-15, S/N E2014 (OpenAirDocs) - Reported make and model: BRITISH AEROSPACE BAE 146-200 (BAE 146-20) - Registry model: [British Aerospace BAE 146 SERIES 200](https://openairdocs.org/model/british-aerospace-bae-146-series-200) (registry code 1500265) (OpenAirDocs) - Category: Airplane - Serial number: E2014 - Engines: LYCOMING ALF-502R 6970 lbs thrust turbo fan - Damage: No damage - Flight: Part 121 - Registered owner: Air Wisconsin - Airworthiness certificate: Standard, Transport - Destination: ATW, APPLETON, WI - Flight plan: IFR - Airport: ORD, Chicago-O'Hare Intl, runway 22L, 8,071 × 150 ft, concrete ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot, aircraft N635US; age 53; flight engineer, airline transport; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 1, valid medical--no waivers/lim.; seat: left; flight hours: 14,250 total - Pilot, aircraft N602AW; age 46; airline transport; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 1, valid medical--no waivers/lim.; seat: left; flight hours: 9,500 total ## Weather - Conditions: Visual (VMC), Day - Wind: 240° at 4 knots - Visibility: 4 statute miles - Lowest ceiling: 2,300 ft broken - Temperature: 39 °F, dew point 25 °F - Altimeter: 29.00 inHg - Observed at: ORD ## FAA reports on this event (2) The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs). - [Incident 19880219071531I](https://openairdocs.org/incident/19880219071531I), Feb 19, 1988: Boeing 747227B, Chicago, IL. ATC operational error led to reduced clearance between two aircraft during takeoff from different runways. - [Incident 19880219071532I](https://openairdocs.org/incident/19880219071532I), Feb 19, 1988: Bac 146200A, Chicago, IL. ATC operational error led to reduced clearance between two aircraft during takeoff from different runways. 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. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.