# NTSB SEA91FA073: Piper PA-30, N7133Y, Butte, MT, March 29, 1991

- Type: NTSB accident investigation
- Classification: Accident · Fatal · Field investigation · Final report
- Date: March 28, 1991, 17:36 local (Mar 29, 1991, 00:36 UTC)
- Place: Butte, MT
- Coordinates: 45.999595, -112.440811 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=45.9996&lon=-112.4408&mi=10
- Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping)
- Highest injury: Fatal
- Injuries: 1 fatal, 1 serious
- Status: Completed, report July 13, 1993
- Report: Approved by Office Director
- NTSB case key (mKey): 41310
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA91FA073
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/41310/pdf
- Page: https://openairdocs.org/ntsb/SEA91FA073

## Probable cause

INADEQUATE INFLIGHT DECISIONS, FUEL STARVATION, AND FAILURE TO PERFORM ALTERNATIVE IFR APPROACH PROCEDURES.  FACTORS INCLUDE OPERATION WITH KNOWN DEFICIENCIES IN EQUIPMENT, DISORIENTATION, AND LACK OF FAMILIARITY WITH THE GEOGRAPHIC AREA.

## Sequence of events

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

- Loss of engine power(total) - nonmechanical, approach
  - 2 engines
  - fluid,fuel - starvation (cause)
  - fuel supply - not used, pilot in command (cause)
  - comm/nav equipment,glide slope receiver - fluctuating (contributing factor)
  - operation with known deficiencies in equipment - attempted, pilot in command (contributing factor)
  - delayed, pilot in command
  - became lost/disoriented, pilot in command (contributing factor)
  - incapacitation(anoxia/hypoxia), pilot in command
  - ifr procedure - not performed, pilot in command (cause)
  - lack of familiarity with geographic area, pilot in command (contributing factor)
  - in-flight planning/decision - inadequate, pilot in command (cause)
- Forced landing, descent - emergency
- In flight collision with terrain/water, landing
  - unsuitable terrain or takeoff/landing/taxi area - encountered

## Analysis

THE PILOT OF THE PIPER PA-30 DECLARED AN EMERGENCY AFTER FAILURE OF BOTH ENGINES, AFTER THREE ILS APPROACH ATTEMPTS. DURING THE LANDING AFTER HIS EMERGENCY DESCENT, THE RIGHT WING-TIP STRUCK THE SNOW-COVERED SURFACE AND THE AIRCRAFT SLID TO A STOP SIDEWAYS.  A TOTAL OF 10.75 GALLONS OF FUEL REMAINED IN THE AIRCRAFT.  THE AIRCRAFT HAD BEEN ALOFT APPROXIMATELY 5.25 HOURS.  WEATHER AT THE DESTINATION AIRPORT WAS VFR.

## Aircraft

- Registration: [N7133Y](https://openairdocs.org/deregistered/N7133Y-2003-05-28), registration cancelled 2003-05-28, S/N 30-155, built 1963 (OpenAirDocs)
- Reported make and model: PIPER PA-30
- Registry model: [Piper PA-30](https://openairdocs.org/model/piper-pa-30) (registry code 7103002) (OpenAirDocs)
- Registry engine: [Lycoming IO-320 series](https://openairdocs.org/engine/lycoming-io-320-series) (registry code 41509, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 30-155
- Engines: LYCOMING IO-320-B1A 160 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Operator: Michael Lynn Heling
- Registered owner: Michael Lynn Heling
- Departed: BIS, BISMARK, ND
- Flight plan: IFR
- Airport: BTM, Bert Mooney

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 33; commercial; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 1, valid medical--no waivers/lim.; toxicology performed; flight hours: 555 total, 68 in this make and model, 314 as pilot in command, 43 in the last 90 days, 16 in the last 30 days, 4 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 300° at 15 knots
- Visibility: 5 statute miles
- Lowest ceiling: 4,500 ft broken
- Temperature: -0 °F, dew point -0 °F
- Altimeter: 29.00 inHg
- Observed at: BTM, 15 nm away

## 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 19910328007779A](https://openairdocs.org/incident/19910328007779A), Mar 28, 1991: Piper PA30, Butte, MT, Substantial damage, 1 fatal. After long high altitude flight missed several ILS approaches above minimums. Diverted to alternate,ran out of fuel

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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