Delta Air Lines Flight 9570
Douglas DC-9 · Wake turbulence
From Dallas Love Field (DAL) to Dallas Love Field (DAL)
Event
- 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
- Accident
- InvestigationHow far the investigation had got when the record was published: preliminary, ongoing, final or completed. Unknown where the source does not say. Glossary
- Unknown
- Event fatalities
- 4 · all aircraft and ground
- Ground fatalities
- 0
- Occupants
- 4
- Survivors
- 0
- InjuriesFatal: death within 30 days. Serious: over 48 hours in hospital within a week, most broken bones, severe bleeding, nerve or organ damage, or serious burns. Minor: anything less. Glossary
- 0 serious · 0 minor (NTSB)
- 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
Douglas DC-9
- Flight
- DL9570
- Aircraft type
- Douglas DC-9
- 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
- N3305L
- Operator
- Delta Air Lines
- Onboard fatalities
- Unknown
- Route
- From Dallas Love Field (DAL)To Dallas Love Field (DAL)
- 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
- Not recorded
- 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
- Approach
- Defining eventThe 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
- Turbulence
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Destroyed
Cause areas
- Miscellaneous › Vortex turbulence
Approximate · Coordinates from the Wikipedia article; not checked against an investigation report.
From the Wikipedia article
On May 30, 1972, Delta Air Lines Flight 9570 crashed while attempting to land at the Greater Southwest International Airport (GSW) in Fort Worth, Texas, during a training flight. All four occupants aboard the training flight were killed. The crash was determined to be caused by the aircraft flying through wake turbulence, and led to sweeping changes in procedures for maintaining minimum safe distance behind aircraft that generate substantial wake turbulence.
Accident
On May 30, 1972, Flight 9570 departed Dallas Love Field in Dallas, Texas, at 06:48 Central Daylight Time, and proceeded to GSW to perform training approaches and landings. Flight 9570 requested an ILS approach to GSW's Runway 13. The clearance was granted, and Flight 9570 was advised that the American Airlines DC-10 was already in the traffic pattern to perform "touch-and-go landings" at GSW. Flight 9570 landed without incident.
After landing at GSW, Flight 9570 received new takeoff and climb-out clearances, made training maneuvers including an ILS missed approach. Flight 9570 then requested approval for landing on Runway 13, behind the American DC-10 which was also inbound for a landing on the same runway. The air traffic controller gave Flight 9570 clearance to land on Runway 13 with an advisory "caution, turbulence". The controller did not advise the DC-9 that they were following a "heavy", though the controller did advise that they were following a DC-10 which experienced pilots should have known was a "heavy" aircraft.
On approach to the runway, the DC-9 began to oscillate about the roll axis, then rolled rapidly to the right. After rolling 90 degrees to the right, the right wingtip struck the runway. The airplane continued to roll to the right, until the fuselage struck the runway in a nearly inverted position. The aircraft was damaged by impact forces, and destroyed by a subsequent fire. All four occupants were killed.
Investigation and cause
Investigation
The National Transportation Safety Board (NTSB) investigated the accident. The manner of the crash suggested to the NTSB that the accident was caused by wake turbulence from the DC-10 it had followed. Prior to the Flight 9570 accident, the Federal Aviation Administration had no specific wake turbulence based aircraft separation standards in place. Instead, separation was determined by air traffic control radar resolution limits and, in some cases, runway occupancy restrictions. However, the rapidly increasing use of large jets that cause substantial wake turbulence, such as the Boeing 747, DC-10, and Lockheed L-1011 TriStar in recent years had increased the risk of wake turbulence related accidents. However, prior to Flight 9570, most accidents involving wake turbulence involved smaller aircraft than the DC-9.
Recognizing wake turbulence as a potential cause, the NTSB performed test and research activities to confirm their hypothesis. The NTSB performed wake vortex testing at the National Aviation Facilities Experimental Center at Atlantic City Airport in New Jersey, initially using a Lockheed L-1011 (a trijet similar in size to the DC-10) and then later using a DC-10 loaned to the NTSB. Colored smoke was emitted from the airport control tower, and observations of the smoke as an L-1011 or DC-10 aircraft flew by the tower provided information about the length of time a vortex would remain after the aircraft was clear.
The NTSB's tests demonstrated that the wake turbulence caused by an aircraft the size of the DC-10 was sufficient to upset the flight of a following DC-9 to the magnitude experienced by Flight 9570. Following these tests, the probable cause of the accident was determined to be:
Text from the Wikipedia article “Delta Air Lines Flight 9570” (revision 1343607783, retrieved 2026-09-18) by its authors, under CC BY-SA 4.0. Extracted as plain text: references, tables, images and some sections are left out. Read the article
NTSB remarks
VORTEX TURB FROM PRECEDING DC-10.TWR GAVE WARNING.CREW UN EVALUATE HAZARD DUE INSUFFICIENT INFO.
NTSB's remark from its 1962–1981 archive, as recorded (abbreviated, at most 98 characters): the archive has no narrative
Sources
Wikipedia article: Delta Air Lines Flight 9570
- Article
- Delta Air Lines Flight 9570
- Revision
- 1343607783 · 2026-03-15 · retrieved 2026-09-18
- Wikidata
- Q5254569
- Licence
- Text CC BY-SA 4.0, by the article's authors; Wikidata CC0; town positions GeoNames (CC BY 4.0)
NTSB record
- Event ID
- 19720530P044008
- Case number
- Unknown
- Dataset
- historical-pre1982
- Source SHA-256
- abe1a933b4b73583d61684309f7f0610c281e3c1de3537c6471bf2a98ba6481d
Where each value comes from
- Record
- Wikipedia article "Delta Air Lines Flight 9570" (page 45597512, revision 1343607783); merged with NTSB case NTSB19720530P044008 (PRE1982 tblFirstHalf (one row per aircraft, grouped by date, place and time))
- Date
- NTSB record NTSB19720530P044008: PRE1982 DATE_OCCURRENCE
- Place and country
- Wikipedia infobox: site; country from NTSB record NTSB19720530P044008
- Map position
- Wikipedia: Wikipedia article coordinates
- Aircraft, operator and route
- NTSB record NTSB19720530P044008: PRE1982 REGIST_NO, ACFT_MAKE, ACFT_MODEL; gaps from Wikipedia infobox: aircraft type, registration, operator, origin and destination; route airports from the linked airport articles' Wikidata codes (OurAirports)
- Operation
- airline flight number in the infobox
- Fatalities
- NTSB record NTSB19720530P044008: PRE1982 TOTAL_ABRD_FATAL of each aircraft, plus people on the ground and others outside the aircraft
- Ground fatalities
- NTSB record NTSB19720530P044008: events.inj_f_grnd
- Summary
- Wikipedia infobox: summary
Source notes (4)
- One occurrence in two sources, merged: the Wikipedia article "Delta Air Lines Flight 9570" and NTSB case NTSB19720530P044008, matched by the same aircraft registration and date. For this US event the NTSB's values are used where the two differ; each value names its source.
- From NTSB's 1962-1981 archive (PRE1982), which holds at most a short remark (98 characters, abbreviated) instead of a narrative; the accident type, phase of flight, causes and conditions are NTSB's codes, decoded as the archive defines them.
- Reviewed means this record passed the site's consistency check, not that it was checked against a narrative or report - there is none to check against.
- The operation category is mapped from the archive's operator and operation codes and has not been reviewed.