Robinson Helicopter Company R44 II accident near Calexico, California, December 6, 2023
On December 6, 2023 at about 1:30 am local time, a 2009 Robinson Helicopter Company R44 II, registered N422DX, was substantially damaged in an accident during maneuvering (low-alt flying) near Calexico, California. It was an aerial application (crop spraying) flight under agricultural flying rules (Part 137). No one was hurt; 1 person was on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The pilot's failure to maintain clearance from power lines during an aerial application flight.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- December 6, 2023 · about 1:30 am local time
- Place
- Calexico, California · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Robinson Helicopter Company R44 II, built 2009
- Registration
- N422DX · registry record · serial 12699
- Damage
- Substantial damage
- Flight
- Aerial application (crop spraying) flight · agricultural flying rules (Part 137)
The NTSB's narrative final · quoted from the NTSB record
The pilot was on an aerial application flight and was maneuvering the helicopter at a low altitude. During a decent to a field, the main rotor blade struck a powerline wire. The pilot felt an unusual vibration and performed a precautionary landing. A postflight examination revealed that a main rotor blade sustained substantial damage. No preaccident mechanical failures or malfunctions with the helicopter that would have precluded normal operation were reported.
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
What happened, in order
- Collision with terrain or object (not controlled flight into terrain) during maneuvering (low-alt flying) defining event
The NTSB's findings
- Personnel issues › Psychological › Attention/monitoring › Monitoring environment › Pilot
- Environmental issues › Physical environment › Object/animal/substance › Wire › Effect on equipment
Pilot
- Certificate: commercial pilot
- Ratings: multi-engine land; single-engine land; instrument: airplane; rotorcraft: helicopter
- Medical certificate: Class 1 (with waivers/limitations)
- Seat: unk
- Injury: no injuries
The aircraft
- Last inspection: inspection type not recorded
- Seats: 4
- Landing gear: fixed
- Engine: Lycoming IO-540-AE1A5 (piston); 0 hours total
- Operator: Merten Aviation Services LLC
The flight
- Flight plan: none
Weather at the time
- Light: daylight
- Visibility: 10 statute miles
- Temperature: 72°F (22°C), dew point 36°F (2°C)
- Altimeter: 30.08 inHg
- Observation at 4:53 pm from KIPL, 11 miles away
Weather report (METAR): METAR KIPL 060053Z AUTO 00000KT 10SM CLR 22/02 A3008 RMK AO2 SLP184 T02170022=
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
2 documents, released by the NTSB on October 22, 2024. View them here, or download them; the NTSB redacts some personal details before release, and this site shows the NTSB's own titles rather than its file names.
| # | Document | What it is | |
|---|---|---|---|
| 1 | Mor - Pilot | PDF, 1 page | View Download |
| 2 | Accident Photo | PDF, 2 pages | View Download |
The same docket at the NTSB · documents without a copy here are fetched from the NTSB when you open them.
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.