Silverado Helicopters Aerospatiale AS350B incident
Aerospatiale AS350B · Incident: airframe, component or system failure en route
From Harry Reid International Airport (LAS) to Grand Canyon National Park Airport (GCN)
Event
- NTSB case
- LAX99IA085
- 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
- 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
- Charter & commuter
- 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
Aerospatiale AS350B
- Aircraft type
- Aerospatiale AS350
- Category
- Helicopter
- 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
- N32GA
- Operator
- Silverado Helicopters
- Onboard fatalities
- Unknown
- Route
- From Harry Reid International Airport (LAS), Las Vegas, NVTo Grand Canyon National Park Airport (GCN), Grand Canyon, AZ
- 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 135: Air Taxi & Commuter
- 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
- En route · descent
- 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
- Minor
Cause areas
- Reason for occurrence undetermined
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
While descending on an aerial tour flight with six passengers, the left side bubble window separated from the helicopter and impacted a tail rotor blade. The pilot made a precautionary landing in the canyon without further incident. Neither the separated window nor its doorframe attachment seal (gasket) was recovered. Examination of the helicopter's tail rotor blade found it bent and scratched with areas of debonded material. The damaged blade was not repairable. During preflight inspection the pilot did not see any damage to the window, and during the flight the left seated passenger was not observed pressing on it. Due to observed cracks in the previous window 4.5 months and 589 flight hours earlier, it had been replaced with a window removed from another helicopter. No maintenance record entry was found for the window installation. The operator's replacement window was manufactured under a FAA Supplemental Type Certificate. The STC holder said that if its 'wedge' window is not properly installed, or if it becomes cracked or damaged due to exposure to harmful cleaning solvents, its integrity may be compromised. The operator reported that if a small crack existed near the window's edge, it may not have been noticed/reported by the pilot due to a lack of conspicuity. The reason(s) for the window separation could not be determined.
Probable cause
The in-flight separation of a side window for undetermined reasons.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record LAX99IA085
- Event ID
- 20001205X00182
- Case number
- LAX99IA085
- 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: 37ae33f0b650bbcd85529a14db18cb04ca28d018fcffe87443c7c78590d672f5; retrieved 2026-09-18T16:59:59.975Z.