# NTSB LAX86DVA09: Hiller UH-12E, N172ET, Delano, CA, June 17, 1986

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Final report
- Date: June 17, 1986, 10:30 local (17:30 UTC)
- Place: Delano, CA
- Location: 35.7732° N, 119.2261° W: Placed by OpenAirDocs from NTSB’s distance and direction from DELANO MUNI (DLO), within about a mile (OpenAirDocs)
- Nearby events: https://openairdocs.org/map.md?lat=35.7732&lon=-119.2261&mi=10
- Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report April 25, 1988
- Report: Approved by Office Director
- NTSB case key (mKey): 24866
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX86DVA09
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/24866/pdf
- Page: https://openairdocs.org/ntsb/LAX86DVA09

## Sequence of events

In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf).

- Airframe/component/system failure/malfunction, takeoff - initial climb
  - rotor system,main rotor blade - failure,partial (cause)
  - maintenance,major repair - improper, company maintenance personnel (cause)
- Loss of control - in flight, takeoff - initial climb
- Forced landing, descent - emergency
  - autorotation - performed, pilot in command
- In flight collision with terrain/water, descent - uncontrolled

## Analysis

THE HELICOPTER ROTOR BLADE DELAMINATED SHORTLY AFTER DEPARTING THE OPERATOR'S NORTH BASE AT DELANO, CA. THE INVESTIGATION DETERMINED THE BLADE CONTAINED EXTENSIVE VOIDS ON THE BOND LINE. THE BLADE WAS REJECTED BY THE MANUFACTURER AS BEING UNAIRWORTHY. THE OPERATOR BOUGHT THE BLADE IN AN AS IS CONDITION. THE OPERATOR COULD NOT PRODUCE ANY YELLOW SERVICEABLE TAGS. INVESTIGATOR'S COULD NOT DETERMINE WHO OVERHAULED THE BLADES.

## Aircraft

- Registration: [N172ET](https://openairdocs.org/deregistered/N172ET-2004-08-18), registration cancelled 2004-08-18, S/N HA3072, built 1978 (OpenAirDocs)
- Reported make and model: HILLER UH-12E
- Registry model: [Hiller UH-12E](https://openairdocs.org/model/hiller-uh-12e) (registry code 4360122) (OpenAirDocs)
- Registry engine: [Lycoming VO-540 series](https://openairdocs.org/engine/lycoming-vo-540-series) (registry code 41534, reciprocating) (OpenAirDocs)
- Category: Helicopter
- Serial number: HA3072
- Airframe hours: 2690
- Engines: ALLISON 250-C20 301 horsepower turbo shaft
- Damage: Substantial damage
- Flight: Positioning, Part 91
- Registered owner: San Joaquin Helicopters
- Airworthiness certificate: Special, Restricted (Special)
- Last inspection: 100 hour, March 11, 1986, 100 hours before
- Destination: RAL, RIVERSIDE, CA
- Airport: DLO, Delano

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 42; commercial; medical: class 2, valid medical--w/ waivers/lim; seat: right; flight hours: 10,000 total, 300 in this make and model, 10,000 as pilot in command, 50 in the last 90 days

## Weather

- Conditions: Visual (VMC), Day
- Wind: calm
- Visibility: 15 statute miles
- Lowest ceiling: none

## FAA reports on this event (1)

The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs).

- [Accident 19860617081429A](https://openairdocs.org/incident/19860617081429A), Jun 17, 1986: Hiller UH12E, Delano, CA, Substantial damage. Parts of the main rotor blade separated in flight. Investigation found the blades were not airworthy. Bogus part.

## Other investigations on N172ET (2)

From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model.

- [NTSB LAX95LA132](https://openairdocs.org/ntsb/LAX95LA132), Mar 12, 1995: Hiller UH-12E (N172ET), Five Points, CA, substantial damage. Probable cause: fuel exhaustion due to the pilot's inattention to the fuel supply.
- [NTSB SEA79FYM08](https://openairdocs.org/ntsb/SEA79FYM08), Dec 22, 1978: Hiller Acft Soloy (N172ET), Lacomb, OR, substantial damage

From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model.

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