LAX05LA060 · Eurocopter France EC135T1
Eurocopter France EC135T1 · Accident: loss of control in flight while maneuvering
From Mesa Gateway Airport (IWA) to Casa Grande Municipal Airport (CGZ)
Event
- NTSB case
- LAX05LA060
- 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
Eurocopter France EC135T1
- Aircraft type
- Eurocopter EC135
- 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
- N135NW
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From Mesa Gateway Airport (IWA), Mesa, AZTo Casa Grande Municipal Airport (CGZ), Casa Grande, 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 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
- Maneuvering
- 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
- Loss of control in flight
- 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
- Aircraft control › Diminished
- Company maintenance personnel › Maintenance, installation, improper
- Rotorcraft flight control, cyclic control rod › Not safetied
Approximate · Coordinates from the NTSB case API, which marks them as estimated or does not say; no uncertainty radius is established.
NTSB narrative
Following the in-flight separation of a main rotor control link, the pilots lost control and the helicopter hit the ground hard and rolled over. The pilots reported that as they turned base in the traffic pattern for landing at the airport, the helicopter pitched up violently and rolled to the right, followed by a hard roll to the left. Both pilots got on the controls and tried to regain control of the helicopter. The pilots lowered the collective and started down for a landing. During the descent, the pitching and rolling continued intermittently with the roll attitude reaching beyond 60 degrees. As the helicopter neared the ground, the pilots flared and the helicopter hit the ground in a tail low attitude and rolled over. A post accident examination of the helicopter, and examination of maintenance records by a Federal Aviation Administration inspector, occurred on site and after recovery. During the course of the examination it was determined that maintenance personnel had removed cyclic control links from the cyclic control levers to check the ball joints for excess free play during an inspection. The links are attached to the cyclic levers with bolts and castle nuts with cotter pins through the castle nuts as a safety locking device. The right lateral cyclic control link was found broken. The nut on the upper bolt was 1/4-inch away from the side of the attachment point. There was no evidence of the cotter pins having been added to the castle nuts after the link inspection/reinstallation.
Probable cause
the separation of a main rotor control link due to improper maintenance installation.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record LAX05LA060
- Event ID
- 20050106X00024
- Case number
- LAX05LA060
- 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: 02baddbffd392d9e0f8ea466391e72ab521f7517cebeff1ac949ff764b1c2b03; retrieved 2026-09-21T19:05:15.351Z.