# NTSB DEN83LA202: Piper PA-11-90, Babb, MT, August 29, 1983

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: August 28, 1983, 19:15 local (Aug 29, 1983, 01:15 UTC)
- Place: Babb, MT
- Coordinates: 48.779529, -113.370613 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=48.7795&lon=-113.3706&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 2 uninjured
- Status: Completed
- Report: Approved by Office Director
- NTSB case key (mKey): 16148
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN83LA202
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/16148/pdf
- Page: https://openairdocs.org/ntsb/DEN83LA202

## Sequence of events

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

- Loss of engine power(partial) - nonmechanical, cruise - normal
  - fuel system - contamination (cause)
  - fluid,fuel - water
- Forced landing, descent - emergency
- On ground/water encounter with terrain/water, landing - roll
  - terrain condition - hidden obstruction(s) (contributing factor)

## Analysis

THE PILOT SAID THAT BEFORE TAKEOFF, HE FUELED THE LEFT TANK OF THE AIRCRAFT. THE RIGHT TANK WAS REPORTEDLY EMPTY. FIVE OR TEN MINUTES AFTER TAKEOFF THE PILOT PUT THE ACFT INTO A 5 DEGREE LEFT FORWARD SLIP FOR ABOUT 30 SECONDS. AS SOON AS THE PILOT RETURNED THE ACFT TO LEVEL FLIGHT, THE ENGINE LOST POWER. THE PILOT ATTEMPTED VARIOUS PROCEDURES, BUT COULD NOT RESTORE POWER TO THE ENGINE. HE MADE A FORCED LANDING ON A SMALL POND. AS THE ACFT SLOWED AND CAME OFF THE STEP, THE LEFT FLOAT STRUCK SUBMERGED WILLOW STICKS AND SANK. THE LEFT WING DROPPED AND STRUCK THE WATER. THE PILOT SAID THAT THIS FUEL TANK DOES NOT HAVE A DRAIN AND UNLESS YOU DRAW APRX 1 GALLON OF FUEL THRU THE GASCOLATOR, WATER WILL NOT SHOWUP.

## Aircraft

- Registration: CFGNB (not matched to a registry record)
- Reported make and model: PIPER PA-11-90
- Category: Airplane
- Serial number: 11-1027
- Airframe hours: 1300
- Engines: CONTINENTAL C90-8F 90 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Registered owner: Kurt Allen Thomas
- Airworthiness certificate: Standard, Normal
- Last inspection: 100 hour, June 5, 1983, 20 hours before
- Departed: CARWAY, ALBERTA

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 26; private; airplane ratings: single-engine sea; medical: class 3, valid medical--no waivers/lim.; seat: center; flight hours: 200 total, 200 in this make and model, 150 as pilot in command, 30 in the last 90 days

## Weather

- Conditions: Visual (VMC), Day
- Wind: 150° at 12 knots
- Visibility: 40 statute miles
- Lowest ceiling: none
- Temperature: 81 °F, dew point 52 °F
- Altimeter: 29.00 inHg
- Observed at: FCA, 49 nm away

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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