FTW99LA045 · Lockheed L-1329
Lockheed L-1329 · Accident: airframe, component or system failure during landing
From William P. Hobby Airport (HOU) to Austin Bergstrom International Airport (AUS)
Event
- NTSB case
- FTW99LA045
- 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
- 0
- 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
- General aviation
- 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
Lockheed L-1329
- Aircraft type
- Lockheed L-1329
- 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
- N787WB
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From William P. Hobby Airport (HOU), Houston, TXTo Austin Bergstrom International Airport (AUS)
- 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 91: General Aviation
- 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 · landing roll
- 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
- Airframe, component or system failure
- 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
- Landing gear, steering system › Fatigue
- Manufacturer › Inadeq substantiation process, inadeq documentation
- Manufacturer › Procedure inadequate
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
During the landing roll, the nose gear settled onto the runway, and the aircraft veered hard to the right. Application of the left brake had no effect. The airplane skidded, exited the runway, struck a runway marker, and collapsed the nose landing gear. The steering actuator had failed, the hydraulic fluid was lost from the steering actuator, and the fuselage received structural damage. The steering actuator assembly, p/n 1501-4, had accumulated 5,938.0 hours since new and had not been repaired or overhauled. Examination of the nose gear steering actuator cylinder by the metallurgist revealed that the cylinder fracture was the result of fatigue cracking initiated by an abrupt machining transition from the 45 degree thread ring chamfer to the straight wall of the cylinder. The engineering drawings appear to depict the radius at the fatigue origin as a continuation of the 0.03 inch to 0.06 inch radius adjacent to the fracture. However, the drawing is not clear on the specific intent of the transition between the nearby radius and the internal threads for the nut.
Probable cause
The steering actuator fatigue failure resulting from inadequate procedure documentation for the manufacturing process.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record FTW99LA045
- Event ID
- 20001211X11434
- Case number
- FTW99LA045
- 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. 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: cdb50643f72e268b55f956fd3a7e4db6aa0c1bb212db4b78040c3aadeb5429f9; retrieved 2026-09-22T16:14:53.028Z.