# NTSB BFO89IA036: Northrop T-38A, N920NS, Washington, DC, May 15, 1989 - Type: NTSB incident investigation - Classification: Incident · No injuries · Incident investigation · Final report - Date: May 15, 1989, 18:41 local (22:41 UTC) - Place: Washington, DC - Location: 38.8951° N, 77.0364° W: Placed by OpenAirDocs: center of Washington, DC, within about 6 miles (OpenAirDocs) - Nearby events: https://openairdocs.org/map.md?lat=38.8951&lon=-77.0364&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 177 uninjured - Status: Completed, report January 3, 1992 - Report: Approved by Office Director - NTSB case key (mKey): 11475 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=BFO89IA036 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/11475/pdf - Page: https://openairdocs.org/ntsb/BFO89IA036 ## Probable cause (aircraft 2) FAILURE OF THE T-38 PILOT (IN THE OTHER AIRCRAFT) TO FOLLOW THE ATC CLEARANCE AND TO MAINTAIN THE PROPER ALTITUDE. FACTORS RELATED TO THE INCIDENT WERE: FAILURE OF AIR TRAFFIC CONTROL (ATC) PERSONNEL TO RECOGNIZE THE T-38'S IMPROPER ALTITUDE IN A TIMELY MANNER, AND ATC PERSONNEL'S DELAY IN INITIATING CORRECTIVE ACTION. ## Probable cause (aircraft 1) FAILURE OF THE PILOT-IN-COMMAND (T-38 PILOT) TO FOLLOW THE ATC CLEARANCE AND TO MAINTAIN THE PROPER ALTITUDE. FACTORS RELATED TO THE INCIDENT WERE: FAILURE OF AIR TRAFFIC CONTROL (ATC) PERSONNEL TO RECOGNIZE THE T-38'S IMPROPER ALTITUDE IN A TIMELY MANNER, AND ATC PERSONNEL'S DELAY IN INITIATING CORRCTIVE ACTION. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Near collision between aircraft, descent - proper altitude - not maintained, pilot in command (cause) - atc clearance - not followed, pilot in command (cause) - monitoring - inadequate, atc personnel(dep/apch) (contributing factor) - traffic advisory - delayed, atc personnel(dep/apch) (contributing factor) - Near collision between aircraft, climb - proper altitude - not maintained, pilot of other aircraft (cause) - atc clearance - not followed, pilot of other aircraft (cause) - monitoring - inadequate, atc personnel(dep/apch) (contributing factor) - traffic advisory - delayed, atc personnel(dep/apch) (contributing factor) ## Analysis (aircraft 2) NASA T-38, N920NS, WAS INBND (HDG EAST) ON A FINKS ONE ARRIVAL TO ANDREWS AFB WITH CLNC TO DSCND TO 8000'. IN THE SAME AREA, PAN AN FLT 140 (AIRBUS A310/N806PA) WAS HDG NORTH AT 7000' AFTER DEPG DULLES (IAD) IAP. THE AIRBUS WAS HANDLED BY IAD APCH CTL. THE T-38 WAS HANDLED BY WASHINGTON (DCA) APCH CTL. THE T-38 PLT DSCNDD THRU 8000' & RPRTD AT 7000'. AT 1ST, THE DCA CTLR DIDN'T REALIZE THE T-38 WAS AT THE WRONG ALT. SHORTLY THEREAFTER, THE CONFLICT ALERT ALARMED & THE DCA CTLR ISSUED A TFC ADZY. THE T-38 PLT IMMEDIATELY CLIMBED TO 8000'. BUT BEFORE HE CLIMBED, RADAR DATA INDCD THE AIRBUS & T-38 PASSED EACH OTR WITH 711' LATERAL CLNC & 100' VERTICAL CLNC. THE AIRBUS PLT STATED HE SAW THE T-38 PASS AHEAD FM LEFT TO RGT. THE IAD CONTROLLER DID NOTICE TFC FOR THE AIRBUS, BUT HE DID NOT ISSUE A TFC ADZRY. ALSO, HE SAID HIS CONFLICT ALERT SYS DID NOT ALARM; RECORDED COMPUTER DATA INDCD THE ALARM HAD OPERATED. ## Analysis (aircraft 1) NASA T-38, N920NS, WAS INBND (HDG EAST) ON A FINKS ONE ARRIVAL TO ANDREWS AFB WITH CLNC TO DSCND TO 8000'. IN THE SAME AREA, PAN AM FLT 140 (AIRBUS A310/N806PA) WAS HDG NORTH AT 7000' AFTER DEPG DULLES (IAD) IAP. THE AIRBUS WAS HANDLED BY IAD APCH CTL. THE T-38 WAS HANDLED BY WASHINGTON (DCA) APCH CTL. THE T-38 PLT DSCNDD THRU 8000' & RPRTD AT 7000'. AT 1ST THE DCA CTLR DIDN'T REALIZE THE T-38 WAS AT THE WRONG ALT. SHORTLY THEREAFTER, THE CONFLICT ALERT ALARMED & THE DCA CTLR ISSUED A TFC ADZY. THE T-38 PLT IMMEDIATELY CLIMBED TO 8000', BUT BEFORE HE CLIMBED, RADAR DATA INDCD THE AIRBUS & T-38 PASSED EACH OTR WITH 711' LATERAL CLNC & 100' VERTICAL CLNC. THE AIRBUS PLT STATED HE SAW THE T-38 PASS AHEAD FM LEFT TO RGT. THE IAD CONTROLLER DID NOTICE TFC FOR THE AIRBUS, BUT HE DID NOT ISSUE A TFC ADZRY. ALSO, HE SAID HIS CONFLICT ALERT SYS DID NOT ALARM; COMPUTER DATA INDCD THE ALARM HAD OPERATED. ## Aircraft 1 - Registration: N920NS (not matched to a registry record) - Reported make and model: NORTHROP T-38A - Category: Airplane - Serial number: 66-8386 - Engines: GE J-85 5000 lbs thrust turbo jet - Damage: No damage - Flight: Public aircraft, Part 91 - Registered owner: National Aero. & Space Admin. - Departed: HOP, FT CAMPBELL, KY - Destination: ADW, ANDREWS AFB, MD - Flight plan: IFR ## Aircraft 2 - Registration: N806PA (not matched to a registry record) - Reported make and model: Airbus Industrie A-310 (A310) - Category: Airplane - Serial number: 342 - Engines: P&W JT9D 50000 lbs thrust turbo fan - Damage: No damage - Flight: Part 121 - Registered owner: Pan American World Airway - Airworthiness certificate: Standard, Transport - Departed: IAD, WASHINGTON, DC - Destination: ORY, PARIS,FRANCE, OF - Flight plan: IFR ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot, aircraft N920NS; age 44; commercial, military; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 1, valid medical--no waivers/lim.; flight hours: 5,345 total, 2,388 in this make and model, 64 in the last 90 days, 20 in the last 30 days - Pilot, aircraft N806PA; age 53; commercial, airline transport; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 1, valid medical--w/ waivers/lim; seat: left; flight hours: 13,000 total, 1,340 as pilot in command ## Weather - Conditions: Instrument (IMC), Day - Wind: 110° at 5 knots - Visibility: 2 statute miles - Lowest ceiling: 800 ft broken - Temperature: 63 °F, dew point 61 °F - Altimeter: 29.00 inHg - Observed at: DCA, 20 nm away 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.