Hiller UH-12E N93478
21 March 1992 · Huron, California, United States · No injuries
Summary
On 21 March 1992 at about 19:00 local time, a Hiller UH-12E registered N93478, operated by Huron AG Helicopters Inc., was involved in an accident near Huron, California, United States. One person was on board and nobody was injured. The aircraft was destroyed. The NTSB has published a probable cause for this accident; it is quoted in full below.
The record
- Date
- at 19:00
- Classification
- Accident
- Location
- Huron, California, United States
- Coordinates
- 36.2002, -120.0900
- Aircraft
- Hiller UH-12E
- Registration
- N93478
- Category
- Helicopter
- Engines
- 1
- Operator
- Huron AG Helicopters Inc.
- Operating rule
- Part 137: Agricultural
- Purpose of flight
- Aerial Application
- Phase of flight
- Not recorded
- Aircraft damage
- Destroyed
- Weather
- VMC
- Light
- Day
- NTSB number
- LAX92LA146
People
Nobody was injured.
| On board | Died | Serious | Minor | Uninjured |
|---|---|---|---|---|
| 1 | 0 | 0 | 0 | 1 |
Probable cause
A SEPARATION OF THE CONTROL ROTOR CUFF DUE TO FATIGUE.
Quoted verbatim from the NTSB record. This site does not paraphrase or interpret it.
Read the full NTSB narrative
THE PILOT EXPERIENCED A SUDDEN VIOLENT MAIN ROTOR VIBRATION WHILE ON A SPRAY RUN OVER AN ORCHARD. WHILE MANEUVERING AT ABOUT 12 FEET ABOVE THE TREE TOPS, ONE OF THE CONTROL ROTOR BLADE ASSEMBLIES SEPARATED FROM THE ROTOR HUB. AN EXAMINATION OF THE SEPARATED CONTROL ROTOR ASSEMBLY REVEALED A FATIGUE CRACK THAT ORIGINATED AT THE ROTOR CUFF RETAINING BOLT HOLE. THE CONTROL ROTOR CUFF IS THE SUBJECT OF A 100-HOUR RECURRING INSPECTION AS A RESULT OF AN AIRWORTHINESS DIRECTIVE (AD). THE AD WAS COMPLIED WITH DURING THE LAST 100-HOUR INSPECTION. THE CUFF HAD ACCUMULATED 88.8 HOURS OF SERVICE SINCE THE LAST 100-HOUR INSPECTION.
Quoted verbatim from the NTSB record.
Other Hiller UH-12E accidents
| Date | Aircraft | Location | Operator | Outcome | Died |
|---|---|---|---|---|---|
| 27 Mar 1992 | Hiller UH-12E | Watsonville, California, United States | Helicair AG Inc. | No injuries | - |
| 6 May 1992 | Hiller UH-12E | Milford, Iowa, United States | Warren Jackson | No injuries | - |
| 26 Sep 1992 | Hiller UH-12E | Coachella, California, United States | West Farm Air, Inc. | No injuries | - |
| 20 Nov 1993 | Hiller UH-12E | Salinas, California, United States | R and B Helicopters Inc. | Minor injuries | - |
| 16 Mar 1993 | Hiller UH-12E | Applegate, Oregon, United States | Croman Corporation | Fatal | 3 |
| 23 Aug 1993 | Hiller UH-12E | Auburn, Washington, United States | Mayse International | No injuries | - |
Other accidents in this area
| Date | Aircraft | Location | Operator | Outcome | Died |
|---|---|---|---|---|---|
| 22 Feb 1992 | Piper PA-28R-201T | Ludlow, California, United States | Higgins, Melvin W & Jean | Minor injuries | - |
| 22 Feb 1992 | Beechcraft C-23 | Fullerton, California, United States | Eldon R. Howe | No injuries | - |
| 23 Feb 1992 | Cessna 150 | San Jose, California, United States | Veda Corporation | Minor injuries | - |
| 23 Feb 1992 | Cessna 182N | San Ardo, California, United States | Soil Service, Inc. | No injuries | - |
| 25 Feb 1992 | Grumman G-164B | Dixon, California, United States | Sunrise Duster, Inc. | No injuries | - |
| 25 Feb 1992 | Bellanca 7ECA | Apple Valley, California, United States | Chester Waite | Serious injuries | - |