Hiller UH-12E N9785C
23 August 1993 · Auburn, Washington, United States · No injuries
Summary
On 23 August 1993 at about 00:00 local time, a Hiller UH-12E registered N9785C, operated by Mayse International, was involved in an accident near Auburn, Washington, United States. 3 people were on board and nobody was injured. The aircraft was substantially damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.
The record
- Date
- at 00:00
- Classification
- Accident
- Location
- Auburn, Washington, United States
- Nearest airport
- Auburn (S50)
- Coordinates
- 47.2995, -122.3109
- Aircraft
- Hiller UH-12E
- Registration
- N9785C
- Category
- Helicopter
- Engines
- 1
- Operator
- Mayse International
- Operating rule
- Part 91: General Aviation
- Purpose of flight
- Unknown
- Phase of flight
- Not recorded
- Aircraft damage
- Substantial
- Weather
- VMC
- Light
- Day
- NTSB number
- SEA93LA181
People
Nobody was injured.
| On board | Died | Serious | Minor | Uninjured |
|---|---|---|---|---|
| 3 | 0 | 0 | 0 | 3 |
Probable cause
FAILURE OF THE CONNECTING ROD BOLT. THE HIGH VEGETATION WAS A FACTOR.
Quoted verbatim from the NTSB record. This site does not paraphrase or interpret it.
Read the full NTSB narrative
DURING A SIGHTSEEING FLIGHT, THE PILOT HEARD A SERIES OF POPS AND THE WARNING LIGHTS FOR THE OIL PRESSURE AND TEMPERATURE ILLUMINATED. THE PILOT INITIATED AN AUTOROTATION TO AN OPEN FIELD. DURING THE LANDING MANEUVER, THE TAIL ROTOR WAS SEPARATED. AN ENGINE INSPECTION REVEALED THAT THE NUMBER 4 CONNECTING ROD SHANK WAS BROKEN INTO THREE PIECES. A METALLURGICAL EXAMINATION OF THE CONNECTING ROD ASSEMBLY REVEALED THAT THE CONNECTING ROD BOLT DISPLAYED A FRACTURE TYPICAL OF A TENSILE OVERSTRESS SEPARATION. THE OTHER CONNECTING ROD BOLT WAS NOT LOCATED.
Quoted verbatim from the NTSB record.
Other Hiller UH-12E accidents
| Date | Aircraft | Location | Operator | Outcome | Died |
|---|---|---|---|---|---|
| 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 |
| 18 Jul 1993 | Hiller UH-12E | Milbank, South Dakota, United States | Bonanza Valley Aviation | Minor injuries | - |
| 11 Aug 1993 | Hiller UH-12E | Dixon, California, United States | Pacific Valley Aviation, Inc. | Serious injuries | - |
| 15 Jan 1993 | Hiller UH-12E | Chinook, Montana, United States | Dept of Interior | Fatal | - |
| 26 Nov 1993 | Hiller UH-12E | Moore Haven, Florida, United States | - | Minor injuries | - |
Other accidents in this area
| Date | Aircraft | Location | Operator | Outcome | Died |
|---|---|---|---|---|---|
| 30 Jan 1993 | Cessna A185F | Inglewood, Washington, United States | Johnson, Everett H. | No injuries | - |
| 16 Feb 1993 | Cessna 120 | Battleground, Washington, United States | Wills, Charles R. | Serious injuries | - |
| 25 Feb 1993 | Beechcraft C-99 | Seattle, Washington, United States | Ameriflight, Inc. | No injuries | - |
| 25 Apr 1993 | Cessna 172C | Darrington, Washington, United States | Roulier, Brent L. | Fatal | 1 |
| 15 Jul 1993 | Piper PA-34-220T | Battleground, Washington, United States | Flightcraft Inc. | Fatal | 1 |
| 18 Aug 1993 | Enstrom F-28C | Seattle, Washington, United States | - | No injuries | - |