DFW08LA030 · Gulfstream Aerospace G-IV
Avn Air Gulfstream Aerospace G-IV · Accident: gear collapsed during landing
From Baton Rouge, LA to Sugar Land Regional Airport (KSGR)
Event
- NTSB case
- DFW08LA030
- 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
- 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
Gulfstream Aerospace G-IV
- Aircraft type
- Gulfstream G-IV
- 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
- N209LS
- Operator
- Avn Air
- Onboard fatalities
- Unknown
- Route
- From Baton Rouge, LATo Sugar Land Regional Airport (KSGR), Sugar Land, 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 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 · flare/touchdown
- 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
- Gear collapsed
- 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
- Flightcrew › Aircraft preflight, improper
- Landing gear, nose gear › Collapsed
Approximate · Coordinates from the NTSB case API, which marks them as estimated or does not say; no uncertainty radius is established.
NTSB narrative
The pilot reported that the flight, approach to landing and touchdown were uneventful. Soon after touchdown, when the nose landing gear touched down, the ground spoilers deployed automatically and the thrust reversers were deployed. The pilot then stated: " When the nose wheels touched down, a violent vibration or shaking was felt, full back force was applied to the control yoke and the vibration eased until the aircraft slowed further and the vibration returned. The nose landing gear collapsed to the right side of the nose and the aircraft skidded to a stop." Damage was confirmed to a forward pressure vessel. Both nose landing gear tires remained inflated through the collapse. The nose gear assembly was shipped to Gulfstream facilities for further examination and analysis. The cockpit voice recorder (CVR) and flight data recorder (FDR) were recovered following the accident. No significant information concerning the event was obtained from the CVR. The data from the FDR indicated that the landing touchdown was not heavy or with excessive drift. The data also indicated that the deceleration of the aircraft increased within seconds of the touchdown consistent with spoiler and thrust reverser deployment. Examination of the nose landing gear revealed that the nose landing collapsed and separation were the result of nose landing gear shimmy. The shimmy developed when the torque link connection to the nose wheel steering/damper unit separated as the result of the improper installation of the nose landing gear upper torque arm pin by the flight crew during the last preflight inspection of the aircraft.
Probable cause
The collapsed of the nose landing gear due to shimmy as the result of the improper installation of the nose landing gear upper torque arm pin by the flight crew during the preflight inspection of the aircraft.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record DFW08LA030
- Event ID
- 20071127X01856
- Case number
- DFW08LA030
- 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. 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: e73a40f379a063b4e830effb421d575884388e99d15a6a05c76c03109173e8e7; retrieved 2026-09-22T03:17:02.295Z.