Cessna 402B accident near Mt. Torbet, Alaska, August 18, 1988
On August 18, 1988 at about 4:03 am local time, a Cessna 402B, registered N5718M, was substantially damaged in an accident near Mt. Torbet, Alaska. It was a flight of an unrecorded kind under charter and air-taxi rules (Part 135). 2 people were killed. The weather was instrument conditions (cloud, fog or low visibility).
The NTSB's probable cause their words, unchanged
The NTSB has not yet published a probable cause for this accident. Investigations usually take one to two years; this page updates when the final report is released.
Source: NTSB aviation accident database, copy made November 2, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- August 18, 1988 · about 4:03 am local time · cases in 1988
- Place
- Mt. Torbet, Alaska
- Type
- Accident
- Injuries
- 2 people were killed.
- Weather
- instrument conditions (cloud, fog or low visibility)
- Aircraft
- Cessna 402B · all 402Bs on the register
- Registration
- N5718M · no longer on the register · serial 402B0354
- Damage
- Substantial damage
- Flight
- Flight of an unrecorded kind · charter and air-taxi rules (Part 135)
The NTSB's narrative final · quoted from the NTSB record
THE ON-DEMAND-CHARTER FLIGHT WAS TO ORIGINALLY PICKUP PASSENGERS AND CARGO BUT A LANDING GEAR PROBLEM FORCED ANOTHER AIRPLANE WITH A MECHANIC TO BE DISPATCHED. THE OTHER AIRPLANE RETURNED WITH THE PASSENGERS AND THE ACCIDENT AIRPLANE WAS REPAIRED BY THE MECHANIC AND DEPARTED AT A LATER TIME WITH THE CARGO ON BOARD. THE AIRPLANE WAS NOT ON A FLIGHT PLAN. INSTRUMENT METEOROLOGICAL CONDITIONS PREVAILED FROM 7000 FEET MSL TO 12,500 FEET MSL AS REPORTED BY THE OTHER COMPANY AIRPLANE. THE AIRCRAFT WAS FOUND ON THE SIDE OF MT. TORBERT AT THE 10,570 FOOT LEVEL. THE PILOT-IN-COMMAND WAS FOUND IN THE RIGHT PILOT SEAT WITH A NON-AVIATION RELATED BOOK IN HIS LAP. THE MECHANIC WAS FOUND IN THE LEFT PILOT SEAT WITH A WORLD AERONAUTICAL CHART, CD-11 OPEN ON HIS LAP. THE MECHANIC HELD A COMMERCIAL PILOTS CERTIFICATE BUT NO INSTRUMENT RATING. THE INVESTIGATION REVEALED WEAKNESSES IN COMPANY OPERATIONS.
The complete narrative as the NTSB published it. The NTSB's docket holds the report as a PDF and any photographs, statements and other documents from the investigation.
The factual record from the NTSB's investigation tables, in plain English
Pilot
- Certificate: airline transport pilot
- Ratings: multi-engine land; instrument: airplane
- Flight time: 3,452 hours in all; 1,248 in this make and model; 202 in the last 90 days; 156 in the last 30 days
- Medical certificate: Class 1 (valid medical--w/ waivers/lim.)
- Seat: rgt
The aircraft
- Airframe total time: 3,051 hours
- Last inspection: annual inspection, August 16, 1988; 5 hours since
- Maximum gross weight: 6,300 lb
- Seats: 10
- Landing gear: retractable
- Engine: Continental TSIO-520-E (piston); 0 hours total
- Operator: Wilburs INC.
The flight
- Departed from: SLQ Sleetmute AK at 9:30 pm
- Destination: MRI Anchorage AK
- Flight plan: none
- Runway 0
Weather at the time
- Light: daylight
- Wind: from 120° at 50 knots
- Visibility: 1 statute miles
- Sky: not recorded
- Temperature: 0°F (-18°C), dew point 0°F (-18°C)
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 2 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
The docket, the folder of records gathered during an investigation (maintenance records, photographs, witness statements, examinations), has not been read from the NTSB for this case yet; the list appears here once it has. Open the docket at the NTSB.
Other NTSB records under N5718M the same tail number, which may have belonged to a different aircraft at the time
Connections how this case links to the rest of the register
- N5718M: not on the register today · the record of its deregistration
- Cessna 402 174 registered today · the model family and its accident history
- Cessna 72,682 aircraft on the register
- Engine: Continental TSIO-520-E 6 aircraft carry this series today · as the NTSB recorded it
- Sleetmute Airport · departed from
- Merrill Field · bound for
- Accidents and incidents in Alaska 5,932 since 1982 · 825 in the last ten years
- Alaska 9,142 aircraft registered
- Other NTSB records under N5718M 2 records · the number may have belonged to another aircraft at the time
The whole map of how records connect · these connections as data: /graph/accident/ANC88FA111.json.
The bigger picture in Aviation Analytics: accidents over time since 1982, by model, by phase of flight and conditions, by place and on the map.
Everything on this page comes from the NTSB's public records. The narrative, probable cause and findings are the NTSB's own words; the coded tables behind the report are written out in plain English, with pilots' ages, home towns and medical details left out. The documents and photographs are the NTSB's docket, shown as the NTSB released them. This site's own text does not name anyone involved, its policy at this time. A preliminary report can change; the final report usually follows one to two years later, and the page is refreshed when it does.