Cape Smythe Air Service Flight 170
Piper PA-31-T3 · Accident: in flight collision with terrain/water on approach
From Point Lay LRRS Airport (PIZ) to Ralph Wien Memorial Airport (OTZ)
Event
- NTSB case
- ANC00LA029
- Event typeAccident: someone killed or seriously injured, or the aircraft substantially damaged (NTSB definition). Incident: an occurrence that affected or could have affected safety, short of that. Glossary
- Accident
- InvestigationHow far the investigation had got when the record was published: preliminary, ongoing, final or completed. Unknown where the source does not say. Glossary
- Completed
- API-reported fatalities
- 0 · all aircraft and ground
- Ground fatalities
- 0
- OperationWhat kind of flying it was, grouped by the rules it flew under: airline (US Part 121), air taxi and commuter (Part 135), general aviation (Part 91 and similar), military or government. Glossary
- Charter & commuter
- WeatherVisual meteorological conditions (VMC): good enough to fly by looking outside. Instrument conditions (IMC): cloud or low visibility, flying by instruments. Glossary
- Instrument Meteorological Cond
Piper PA-31-T3
- Aircraft type
- Piper PA-31
- Category
- Airplane
- RegistrationThe aircraft's tail number, such as N12345 or G-ABCD. Registrations are reissued, so the same one years apart can be a different aircraft. Glossary
- N219CS
- Operator
- Cape Smythe Air Service
- Onboard fatalities
- Unknown
- Route
- From Point Lay LRRS Airport (PIZ), POINT LAY, AKTo Ralph Wien Memorial Airport (OTZ)
- Aircraft age
- Not recorded
- Flight rulesThe regulations the flight operated under: in the US, Part 91 (general aviation), Part 121 (airlines), Part 135 (air taxi and commuter) and others; for flights abroad, the NTSB's coarser commercial or non-commercial code. Glossary
- Part 135: Air Taxi & Commuter
- Phase of flightThe stage of the flight when things started to go wrong: standing, taxi, takeoff, initial climb, en route, maneuvering, approach or landing. Glossary
- Approach · IFR final approach
- First occurrenceThe single coded event the NTSB judges best describes what happened (records from 2008 on). Older records name the first occurrence in the sequence instead. Glossary
- In flight collision with terrain/water
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Substantial
Cause areas
- Pilot in command › Minimum descent altitude, exceeded
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The airplane collided with frozen pack ice, three miles from the airport, during a GPS instrument approach. Instrument conditions of 3/4 mile visibility in snow and fog were reported at the time of the accident. The pilot stated that he began a steep descent with the autopilot engaged. He indicated that as the airplane crossed the final approach course, the autopilot turned the airplane inbound toward the airport. He continued the steep descent, noted the airplane had overshot the course, and the autopilot was not correcting very well. He disengaged the autopilot and manually increased the correction heading to intercept the final approach course. During the descent he completed the landing checklist, extended the landing gear and flaps, and was tuning both the communications and navigation radios. The pilot said he looked up from tuning the radios to see the sea ice coming up too quickly to react, and impacted terrain. The pilot relayed there were no preaccident anomalies with the airplane, and that he 'did not stay ahead of the airplane.'
Probable cause
The pilot descended below the minimum descent altitude. Factors associated with this accident were the task overload of the pilot during the instrument approach, and not performing a level off.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record ANC00LA029
- Event ID
- 20001212X20442
- Case number
- ANC00LA029
- Dataset
- historical-pre2008
- Source SHA-256
- 89e2df6d848e7ab3b42e7d7c7a03ff403303057a26ca04c95b3ea67201c3ce74
Source notes (5)
- Unreviewed is an editorial label, not an investigation status. API-sourced is not report-checked or human-reviewed. Explicit event totals are used without summing aircraft injury tables; onboard allocation is withheld. Unknown values remain unknown. The operation category is mapped from the NTSB-reported FAR part and has not been reviewed.
- Filled from the NTSB case API where the bulk record had no value: investigation status. Values present in the bulk record are kept.
- The date is the local date, which is the same as the UTC date the NTSB stores.
- API snapshot SHA-256: 2387f445d302c2d8daf3b67ef7f911f948516656616608763e581f61a6e99a99; retrieved 2026-09-18T16:48:37.019Z.
- The NTSB's operator name is blank for N219CS; the operator shown is the name the NTSB's other records give its FAA operator code, CSAA.