# NTSB ANC89LA026: Cessna 185, N70087, Porcupine Lodge, AK, December 21, 1988

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: December 21, 1988, 13:40 local (17:40 UTC)
- Place: Porcupine Lodge, AK
- Phase of flight: [Taxi](https://openairdocs.org/ntsb-phases/250) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 3 uninjured
- Status: Completed, report December 6, 1989
- Report: Approved by Office Director
- NTSB office: Alaska Regional Office
- NTSB case key (mKey): 5154
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC89LA026
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/5154/pdf
- Page: https://openairdocs.org/ntsb/ANC89LA026

## Sequence of events

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

- On ground/water encounter with terrain/water, taxi - to takeoff
  - terrain condition - weak ice (contributing factor)
  - unsuitable terrain or takeoff/landing/taxi area - selected, pilot in command (cause)
  - preflight planning/preparation - inadequate, pilot in command (contributing factor)

## Analysis

THE AIRCRAFT WAS TAXIING FOR TAKEOFF ON THE FROZEN PORCUPINE RIVER IN RURAL ALASKA WHEN THE RIGHT MAIN LANDING GEAR BROKE THROUGH THE RIVER ICE, ALLOWING THE RIGHT WING TO STRIKE THE ICE. THE PILOT STATED THAT HE HAD LANDED ON THE RIVER NEAR THE PORCUPINE LODGE AT A SITE THAT HAD BEEN DESIGNATED BY THE OPERATOR OF THE LODGE AS A LANDING SITE. HE EXPERIENCED NO PROBLEMS DURING THE LANDING, AND ASSUMED THAT THE ICE WAS THICK ENOUGH TO SUPPORT THE WEIGHT OF HIS AIRPLANE. DURING THE TAXI DOWNSTREAM FOR TAKEOFF, THE RIGHT MAIN LANDING GEAR TIRE AND SKI BROKE THROUGH THE ICE INTO APPROXIMATELY FOUR FEET OF WATER.

## Aircraft

- Registration: [N70087](https://openairdocs.org/deregistered/N70087-2011-06-16), registration cancelled 2011-06-16, S/N 18501953, built 1971 (OpenAirDocs)
- Reported make and model: CESSNA 185
- Registry model: [Cessna A185E](https://openairdocs.org/model/cessna-a185e) (registry code 2072818) (OpenAirDocs)
- Registry engine: [Continental IO-520 series](https://openairdocs.org/engine/continental-io-520-series) (registry code 17032, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 18501953
- Airframe hours: 4342
- Engines: CONTINENTAL IO-520D 300 horsepower reciprocating
- Damage: Substantial damage
- Flight: Part 135
- Operator: Yukon Air Service
- Registered owner: Dowding, Roger D
- Airworthiness certificate: Standard, Normal
- Last inspection: Annual, December 5, 1988, 10 hours before
- Destination: FORT YUKON, AK
- Flight plan: VFR
- Airport: NONE, Porcupine River

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 38; commercial; airplane ratings: single-engine sea, multi-engine land, single-engine land; instrument ratings: airplane; medical: class 2, valid medical--no waivers/lim.; seat: left; flight hours: 10,000 total, 5,000 in this make and model, 85 in the last 90 days, 25 in the last 30 days, 2 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: calm
- Visibility: 35 statute miles
- Lowest ceiling: 4,000 ft overcast

## 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 19881221055429A](https://openairdocs.org/incident/19881221055429A), Dec 21, 1988: Cessna A185F, Porcupine Lodge, AK, Substantial damage. Right gear of wheel, ski aircraft, broke through the ice on a river during taxi for takeoff. Right wing damaged.

## Other investigations on N70087 (3)

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 ANC93LA170](https://openairdocs.org/ntsb/ANC93LA170), Aug 30, 1993: Cessna 185 (N70087), Hulahula River, AK, destroyed, 1 fatal. Probable cause: THE PILOT IN COMMAND'S ATTEMPTED VFR FLIGHT INTO IMC CONDITIONS. FACTORS CONTRIBUTING TO THE ACCIDENT WERE THE HIGH TERRAIN AND THE OBSCURATION.
- [NTSB ANC90LA180](https://openairdocs.org/ntsb/ANC90LA180), Sep 18, 1990: Cessna 185 (N70087), Upper Colleen, AK, substantial damage. Probable cause: THE PILOT-IN-COMMAND'S FAILURE TO SELECT SUITABLE TERRAIN FOR LANDING. CONTRIBUTING TO THE ACCIDENT WAS THE ROUGH AND UNEVEN TERRAIN.
- [NTSB FTW80DRD36](https://openairdocs.org/ntsb/FTW80DRD36), Jun 3, 1980: Cessna 185 (N70087), Morgan City, LA, 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.

---
OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.