Eurocopter AS-350-B2 accident near Scottsdale, Arizona, July 1, 2004
On July 1, 2004 at about 10:00 pm local time, a Eurocopter AS-350-B2 (helicopter), registered N513TS, was destroyed in an accident near Scottsdale, Arizona (Scottsdale airport). It was a flight test under general aviation rules (Part 91). 2 people had minor injuries. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
Inadvertent in-flight engagement of the collective down lock, which resulted in an uncontrolled descent and ground impact. The collective down lock engagement was caused by the improper installation and/or adjustment of the collective locking system, which reduced the clearance between the locking plate and the collective control. A factor was the pilot’s decision to embark on a maintenance test flight after encountering difficulty disengaging the collective lock release during previous hover tests.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- July 1, 2004 · about 10:00 pm local time
- Place
- Scottsdale, Arizona · Scottsdale · map
- Type
- Accident
- Injuries
- 2 people had minor injuries.
- Weather
- visual conditions (good weather)
- Aircraft
- Eurocopter AS-350-B2 · all AS-350-B2s on the register
- Registration
- N513TS · registry record · serial 2664
- Damage
- Destroyed
- Flight
- Flight test · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
While performing a maintenance check flight, the collective down lock engaged, which resulted in an uncontrolled descent and collision with terrain. The pilot and a mechanic were to fly a maintenance flight check of the engine and perform a rotor track and balance. He entered a descent at approximately 1,200 feet above ground level (agl) and prepared to level off at approximately 700 feet agl. When he tried to pull up on the collective, the collective would not move and was observed latched by the collective down lock. He and the mechanic tried to unlatch the collective from the down lock, but they did not have enough time before he had to flare the helicopter for landing. With the collective stuck in flat pitch, they landed hard and with forward speed. The flight crew evacuated the helicopter once it had come to rest. An ensuing post accident fire destroyed the helicopter. A new after market avionics control panel had been installed and the collective down lock, which is secured to the panel, was adjusted prior to the flight. The down lock attaches to the lower section of avionics panel. When the collective is lowered to the lower pitch stop the clearance between the collective and the down lock is about 0.16 inches. The down lock is a flexible plate that is free to vibrate with the helicopter's normal rhythms. In the original factory installation, the clearance between the down lock and the collective is 0.3 inches. This is the second known accident where the collective lock has inadvertently engaged in flight with this particular after market avionics panel installed. The manufacturer of the aftermarket avionics panel provided installation information indicating that maintenance personnel must bend the collective locking plate such that the locking plate will spring away from the collective lock button. Examination of the accident aircraft’s locking plate indicated that the locking plate bend was likely reversed, allowing the locking plate to spring toward the lock button.
The complete narrative as the NTSB published it. The NTSB's docket holds the report as a PDF and any photographs, statements and other documents from the investigation.
The factual record from the NTSB's investigation tables, in plain English
Pilot
- Certificate: flight instructor, commercial pilot
- Ratings: single-engine land; instructor: helicopter; instructor: instrument helicopter; instrument: airplane; instrument: helicopter; rotorcraft: helicopter
- Flight time: 6,200 hours in all; 2,000 in this make and model; 60 in the last 90 days; 20 in the last 30 days; 6,000 as pilot in command; 2,700 on instruments
- Last flight review: June 1, 2004
- Medical certificate: Class 2 (valid medical--no waivers/lim.)
- Seat: rgt
- Injury: minor injuries
The aircraft
- Airframe total time: 2,252 hours
- Last inspection: 100-hour inspection, July 1, 2004; 0.3 hours since
- Maximum gross weight: 4,961 lb
- Seats: 6
- Landing gear: fixed
- Engine: Turbomeca Arriel 1D1 (turboshaft); 0 hours total
- Fire on the ground
The flight
- Departed from: KSDL Scottsdale AZ at 7:30 pm
- Flight plan: none
Weather at the time
- Light: daylight
- Wind: from 160° at 8 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 97°F (36°C), dew point 46°F (8°C)
- Altimeter: 29.95 inHg
- Observation at 9:53 pm from KSDL, 7 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 2 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
The docket, the folder of records gathered during an investigation (maintenance records, photographs, witness statements, examinations), has not been read from the NTSB for this case yet; the list appears here once it has. Open the docket at the NTSB.
Everything on this page comes from the NTSB's public records. The narrative, probable cause and findings are the NTSB's own words; the coded tables behind the report are written out in plain English, with pilots' ages, home towns and medical details left out. The documents and photographs are the NTSB's docket, shown as the NTSB released them. This site's own text never names anyone involved. A preliminary report can change; the final report usually follows one to two years later, and the page is refreshed when it does.