Cessna 172 accident near Salmon, Idaho, July 2, 2016
On July 2, 2016 at about 5:00 pm local time, a 1964 Cessna 172, registered N7748U, was substantially damaged in an accident during maneuvering near Salmon, Idaho (Lemhi County Airport). It was an instructional flight under general aviation rules (Part 91). No one was hurt; 2 people were on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
A loss of engine power due to water in the fuel system. Contributing to the accident was an inadequate preflight inspection that failed to eliminate water from the fuel system.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- July 2, 2016 · about 5:00 pm local time
- Place
- Salmon, Idaho · Lemhi County Airport · map
- Type
- Accident
- Injuries
- No one was hurt; 2 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Cessna 172 E, built 1964 · all 172s on the register
- Registration
- N7748U · no longer on the register · serial 17251748
- Damage
- Substantial damage
- Flight
- Instructional flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The flight instructor stated that during an instructional flight, he configured the airplane for a simulated engine failure by applying carburetor heat and decreasing the engine power. The student pilot followed emergency procedures, used the checklist, and prepared to land. When the carburetor heat control was pushed back in and the throttle was advanced, the engine suddenly lost power. The flight instructor tried restarting the engine to no avail and initiated a forced landing, during which the airplane struck a fence. Postaccident examination of the airplane revealed that the original inline fuel strainer was replaced with an aftermarket inline fuel strainer with a manual sump valve on the strainer bowl. The inline fuel strainer drain knob from the original fuel strainer was removed from the instrument panel. The fuel strainer was drained and found to be filled about 3/4 with water. The student pilot stated that the only sumps that were drained during the preflight inspection were the wing tank sumps. He further stated that he did not know about the fuel strainer having a sump and that the flight instructor never told him about it. The flight instructor stated that he performed a preflight inspection after the student pilot had drained the wing tanks and fuel strainer sumps. He further stated that he thought the student pilot found some water in the left wing tank but did not drain the fuel strainer. It is likely that the engine lost power due to water in the inline fuel strainer, which led to the forced landing.
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
What happened, in order
- Off-field or emergency landing during landing
- Collision with terrain or object (not controlled flight into terrain) during landing (landing roll)
- Fuel contamination during maneuvering defining event
The NTSB's findings
- cause Aircraft › Fluids/misc hardware › Fluids › Fuel › Fluid condition
- Environmental issues › Physical environment › Object/animal/substance › Fence/fence post › Contributed to outcome
- factor Personnel issues › Task performance › Inspection › Preflight inspection › Student/instructed pilot
- factor Personnel issues › Task performance › Inspection › Preflight inspection › Instructor/check pilot
Flight instructor
- Certificate: airline transport pilot, flight instructor, flight engineer
- Ratings: multi-engine land; single-engine land; single-engine sea; instructor: airplane multi-engine; instructor: airplane single-engine; instructor: instrument airplane; instrument: airplane
- Flight time: 35,000 hours in all
- Medical certificate: Class 1
- Seat: rgt
- Injury: no injuries
Dual student
- Certificate: student
- Flight time: 20 hours in all; 9 in this make and model
- Seat: left
- Injury: no injuries
The aircraft
- Last inspection: inspection type not recorded
- Seats: 4
- Landing gear: fixed
- Engine: Cont Motor O-300 SER (piston); 0 hours total
The flight
- Departed from: Salmon ID
- Destination: Salmon ID
Weather at the time
- Light: daylight
- Wind: from 360° at 3 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 73°F (23°C), dew point 48°F (9°C)
- Altimeter: 29.98 inHg
- Observation at 4:55 pm from KSMN, 8 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 2 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
3 documents, released by the NTSB on December 9, 2019. View them here, or download them; the NTSB redacts some personal details before release, and this site shows the NTSB's own titles rather than its file names.
| # | Document | What it is | |
|---|---|---|---|
| 1 | Faa-record of Teardown Inspection | PDF, 3 pages | View Download |
| 2 | Supplemental Type Certificate-inline Fuel Strainer | PDF, 1 page | View Download |
| 3 | FAA Photo Array | PDF, 5 pages | View Download |
The same docket at the NTSB · documents without a copy here are fetched from the NTSB when you open them.
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 never names anyone involved. A preliminary report can change; the final report usually follows one to two years later, and the page is refreshed when it does.