United Air Lines Flight 401
Boeing 737 924ER · Accident: tailstrike during landing
From Reno Tahoe International Airport (KRNO) to Denver International Airport (KDEN)
Event
- NTSB case
- DCA19CA169
- 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
- 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
Boeing 737 924ER
- 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
- N75436
- Operator
- United Air Lines
- Onboard fatalities
- Unknown
- Route
- From Reno Tahoe International Airport (KRNO), Reno, NVTo Denver International Airport (KDEN), Denver, CO
- Aircraft age
- About 10 years (built 2009)
- 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
- Landing · flare/touchdown
- 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
- Tailstrike
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Substantial
Cause areas
- Personnel issues › Action/decision
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
On June 9, 2019, about 1555 MDT, United Airlines flight 401, a B737-924ER, N75436, experienced a tailstrike during landing at Denver International Airport (DEN), Denver, Colorado. There were no injuries to the 184 passengers and crew onboard. The airplane received substantial damage. The regularly scheduled domestic passenger flight was operating under 14 Code of Federal Regulations Part 121 from Reno International Airport (RNO), Reno, Nevada to DEN. The first officer (FO) was the pilot flying and the captain was the pilot monitoring. During short final, the FO noticed he was about 5 knots fast, and about 50 feet above the runway, started to slowly reduce power and start the landing flare. At touchdown the airplane bounced. The FO was about to advance throttles for a go-around, when the captain took control and continued the landing after a second bounce. During the post flight walk around, the flight crew observed that the lower aft fuselage had sustained damaged due to a tailstrike. Maintenance examination of the airplane found that the tailskid cartridge was compressed and there was substantial damage to the fuselage skin, frames, stringer clips and shear ties between fuselage station 827 to 907 and deformed stringers 27L and 27R.
Probable cause
the early initiation of the landing flare that resulted in a high pitch attitude and tailstrike.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record DCA19CA169
- Event ID
- 20190619X25315
- Case number
- DCA19CA169
- Dataset
- full-current
- Source SHA-256
- 5cf380f0061817c0331a6b2d8cc7e0ee3a79bea469a1001dc5c10e56f35f5ab3
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. 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: 58f5adca7e038e8e085bd08a3b6751260458f4855cba8e7cd36f880850004932; retrieved 2026-09-16T09:18:02.045Z.