Delta Air Lines Flight 1521
Boeing 737-347 and Continental Airlines Boeing 737-524 · Incident: near collision between aircraft during takeoff
Event
- NTSB case
- FTW01IA183
- Event typeAccident: someone killed or seriously injured, or the aircraft substantially damaged (NTSB definition). Incident: an occurrence that affected or could have affected safety, short of that. Glossary
- Incident
- InvestigationHow far the investigation had got when the record was published: preliminary, ongoing, final or completed. Unknown where the source does not say. Glossary
- Completed
- API-reported fatalities
- 0 · all aircraft and ground
- Ground fatalities
- Unknown
- OperationWhat kind of flying it was, grouped by the rules it flew under: airline (US Part 121), air taxi and commuter (Part 135), general aviation (Part 91 and similar), military or government. Glossary
- Airline
- WeatherVisual meteorological conditions (VMC): good enough to fly by looking outside. Instrument conditions (IMC): cloud or low visibility, flying by instruments. Glossary
- Visual Meteorological Cond
Aircraft 1 · Boeing 737-347
- Aircraft type
- Boeing 737
- Category
- Airplane
- RegistrationThe aircraft's tail number, such as N12345 or G-ABCD. Registrations are reissued, so the same one years apart can be a different aircraft. Glossary
- N308WA
- Operator
- Delta Air Lines
- Onboard fatalities
- Unknown
- Route
- From Dallas Fort Worth International Airport (DFW), DFW Airport, TXTo Oakland San Francisco Bay Airport (OAK), Oakland, CA
- Aircraft age
- Not recorded
- Flight rulesThe regulations the flight operated under: in the US, Part 91 (general aviation), Part 121 (airlines), Part 135 (air taxi and commuter) and others; for flights abroad, the NTSB's coarser commercial or non-commercial code. Glossary
- Part 121: Air Carrier
- Phase of flightThe stage of the flight when things started to go wrong: standing, taxi, takeoff, initial climb, en route, maneuvering, approach or landing. Glossary
- Takeoff
- First occurrenceThe single coded event the NTSB judges best describes what happened (records from 2008 on). Older records name the first occurrence in the sequence instead. Glossary
- Near collision between aircraft
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Minor
Aircraft 2 · Boeing 737-524
- Aircraft type
- Boeing 737
- Category
- Airplane
- RegistrationThe aircraft's tail number, such as N12345 or G-ABCD. Registrations are reissued, so the same one years apart can be a different aircraft. Glossary
- N33635
- Operator
- Continental Airlines
- Onboard fatalities
- Unknown
- Route
- From Cleveland Hopkins International Airport (CLE), Cleveland, OHTo Dallas Fort Worth International Airport (DFW), DFW Airport, TX
- Aircraft age
- Not recorded
- Flight rulesThe regulations the flight operated under: in the US, Part 91 (general aviation), Part 121 (airlines), Part 135 (air taxi and commuter) and others; for flights abroad, the NTSB's coarser commercial or non-commercial code. Glossary
- Part 121: Air Carrier
- Phase of flightThe stage of the flight when things started to go wrong: standing, taxi, takeoff, initial climb, en route, maneuvering, approach or landing. Glossary
- Taxi · from runway
- First occurrenceThe single coded event the NTSB judges best describes what happened (records from 2008 on). Older records name the first occurrence in the sequence instead. Glossary
- Near collision between aircraft
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- None
Cause areas
- Atc personnel(lcl/gnd/clnc) › Atc clearance, premature
- Atc personnel(lcl/gnd/clnc) › Procedures/directives, not complied with
- Atc personnel(lcl/gnd/clnc) › Visual separation, not maintained
Approximate · Coordinates from the NTSB case API, which marks them as estimated or does not say; no uncertainty radius is established.
NTSB narrative
A Boeing 737 was cleared to takeoff on runway 18L at the Dallas/Fort Worth International Airport. After landing on runway 18R, another Boeing 737 took the high speed exit onto taxiway Whiskey Mike and was cleared to cross runway 18L. The pilots of both aircraft saw a possible impending collision and took evasive action. The taxiing aircraft continued to the gate and deplaned the passengers. The departing aircraft continued the takeoff, returned to the airport and landed. Examination of this airplane revealed damage to the skin on the underside of the tail. At the time of the runway incursion, the West air traffic control tower's ground control west one and local west one controller positions were combined. The west air traffic control tower supervisor-in-charge was operating the flight data position along with performing his own supervisory duties. During this time, a National Air Traffic Controllers Association representative had entered the tower cab and was having a meeting with the supervisor-in-charge. In an interview, the incident controller reported that he did not scan runway 18L before clearing the taxiing aircraft to cross. FAA Order 7110.65, Air Traffic Control Handbook, paragraph 3-1-3, "Use of Active Runways," states, "The local controller has primary responsibility for operations conducted on the active runway and must control the use of those runways." Paragraph 3-1-12, "Visually Scanning Runways," states that, "Local controllers shall visually scan runways to the maximum extent possible."
Probable cause
The local controller clearing the taxiing aircraft to cross the runway in front of the aircraft on takeoff roll. Contributing factors were the local controller's failure to follow FAA procedures and directives to visually scan the runway prior to issuing the crossing clearance, the local controller’s excessive workload, and the tower supervisor's inadequate supervision.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record FTW01IA183
- Event ID
- 20010821X01739
- Case number
- FTW01IA183
- Dataset
- historical-pre2008
- Source SHA-256
- 89e2df6d848e7ab3b42e7d7c7a03ff403303057a26ca04c95b3ea67201c3ce74
Source notes (4)
- Unreviewed is an editorial label, not an investigation status. API-sourced is not report-checked or human-reviewed. Explicit event totals are used without summing aircraft injury tables; onboard allocation is withheld. Unknown values remain unknown. The operation category is mapped from the NTSB-reported FAR part and has not been reviewed.
- Filled from the NTSB case API where the bulk record had no value: investigation status, coordinates, damage. Values present in the bulk record are kept.
- The date is the local date, which is the same as the UTC date the NTSB stores.
- API snapshot SHA-256: 78edd8c69e5e0223c97e741674f9981c257f4f23d20db74276568ae509c44ad0; retrieved 2026-09-18T16:10:32.062Z.