# Accident 19980602012139A: Hiller UH12E, Deleaplaine, AR, June 2, 1998

- Type: FAA accident report (Accident/Incident Data System), as reported
- Date: June 2, 1998, 18:15 local time
- Place: Deleaplaine, AR
- Damage: Substantial damage
- Phase of flight: Fcd/Prec Ldg From Cruise
- Operating rules: Agricultural (Part 137)
- Operator: ZHBG
- Location: 36.2292° N, 90.7196° W: From the FAA, an estimate near the named town, within about 3 miles
- Nearby events: https://openairdocs.org/map.md?lat=36.2292&lon=-90.7196&mi=10
- Aircraft: N4028T, a cancelled registration (https://openairdocs.org/deregistered/N4028T-1999-06-10) (OpenAirDocs)
- Registry model: Hiller UH-12E (registry code 4360122, https://openairdocs.org/model/hiller-uh-12e) (OpenAirDocs)
- Reported make and model: HILLER UH12E
- Reported engine: LYC VO540C2A
- People aboard: 1
- Fatal injuries: 0
- Pilot flight hours: 22,000 total, 8,000 in this make and model
- NTSB investigation: [NTSB FTW98LA253](https://openairdocs.org/ntsb/FTW98LA253) (OpenAirDocs)
- FAA source: FAA Aviation Safety Information Portal (https://asip.faa.gov/)
- Page: https://openairdocs.org/incident/19980602012139A

## Narrative

As the FAA filed it, in capitals; the FAA replaces private details with ^PRIVACY DATA OMITTED^.

ACFT EXPERIENCED ENGINE PROBLEMS, PILOT MADE EMERG LANDING IN THE FIELD, BROKE THE SKID, MAIN ROTOR STRUCK THE GROU (.4)THE HELICOPTER WAS TRAVELING IN AN EASTERLY DIRECTION AT AN AIRSPEED OF 60 KNOTS, WHILE MAINTAINING A CONSTANT 5 FOOT CLEARANCE OVER THE RICE FIELD, WHEN THE TRANSMISSION FAILED. THE PILOT TURNED THE HELICOPTER TO THE RIGHT TO AVOID A TALL TREE, AS HE SIMULTANEOUSLY INITIATED A FORCED LANDING. DURING THE TOUCHDOWN ON SOFT GROUND, BOTH SKIDS AND THE COLLAPSED AND THE TAILBOOM WAS SEVERED BY THE MAIN ROTOR BLADES. ACCORDING TO THE MAINTENANCE RECORDS, THE MAIN TRANSMISSION (PART NUMBER 23700-9, SERIAL NUMBER 617), WHICH HAS A RECOMMENDED TBO OF 1,200 HOURS, HAD ACCUMULATED 1,048 HOURS SINCE ITS LAST OVERHAUL IN 1993. ACCORDING TO THE MANUFACTURER, THE 23700-9 TRANSMISSIONS ARE SUBJECT TO A RECURRING INSPECTION OF THE OIL FILTER EVERY 50 FLIGHT HOURS IN ACCORDANCE WITH AIRWORTHINESS DIRECTIVE 81-17-03. ACCORDING TO THE MAINTENANCE LOGBOOKS, THE LAST COMPLIANCE WITH AD 81-17-03 WAS 340 HOURS PRIOR TO THE ACCIDENT, ON MARCH 26, 1996. EXAMINATION OF THE TRANSMISSION BY THE MANUFACTURER'S REPRESENTATIVE REVEALED A MASSIVE FAILURE OF THE                                   FIRST STAGE PLANETARY GEAR SYSTEM DUE TO LACK OF LUBRICATION. (-23) COMMERCIAL PILOT KENNETH MCDOWELL, WHILE OPERATING UH-12E, N4028T, WAS PERFORMING AERIAL APPLICATIONS ABOUT 4 MILES EAST OF DELAPLAINE, AR. PILOT HEARD A LOUD POP AND GRINDING SOUND, ENGINE OVER REVVED. AIRCRAFT LANDED IN FIELD. MAIN ROTOR HIT GROUND AND WAS CHOPPED IN HALF. SUSPECTED TRANSMISSION FAILURE.

## The NTSB's investigation of this event (1)

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 FTW98LA253](https://openairdocs.org/ntsb/FTW98LA253), Jun 2, 1998: Hiller UH-12E (N4028T), Delaplaine, AR, substantial damage. Probable cause: The failure of maintenance personnel to comply with and airworthiness directive, which resulted in failure of the planetary gear due to lack of lubrication. A contributing factors was the lack of…

## Other reports on N4028T (2)

Matched to the same aircraft by N-number and date.

- [Incident 19940620029349I](https://openairdocs.org/incident/19940620029349I), Jun 20, 1994: Hiller UH12E (N4028T), Arcadis, LA, Minor damage. Tried to hover taxi with fuel hose attached to fuel tank. Made hard landing.
- [Accident 19890928036999A](https://openairdocs.org/incident/19890928036999A), Sep 28, 1989: Hiller UH12E (N4028T), Hudsonville, MI, Substantial damage. Vibration on climbout, main rotor severed tailboom. Crashed nose down. Main rotor torsion pins broke. Prior cracks.

From the FAA Accident/Incident Data System. Reports are matched to registry aircraft by N-number and event date, checked against the reported make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. For accidents, the NTSB's own investigation is the fuller record.

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