Piper PA 18-150 accident near Murphy, Idaho, November 3, 2017
On November 3, 2017 at about 3:15 pm local time, a 1968 Piper PA 18-150, registered N4393Z, was substantially damaged in an accident during initial climb near Murphy, Idaho (Pvt Airstrip airport). It was a personal flight under general aviation rules (Part 91). 1 person was killed and 1 person was seriously injured. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
Failure of the left aileron control cable that resulted in a loss of aircraft control during takeoff. Contributing to the accident was inadequate maintenance inspections to the aileron cable connections.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- November 3, 2017 · about 3:15 pm local time
- Place
- Murphy, Idaho · Pvt Airstrip · map
- Type
- Accident
- Injuries
- 1 person was killed and 1 person was seriously injured.
- Weather
- visual conditions (good weather)
- Aircraft
- Piper PA 18-150 A150, built 1968 · all PA 18-150s on the register
- Registration
- N4393Z · registry record · serial 18-8724
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The flight of two airplanes landed at a dirt airstrip for a short break after flying in the area to spot elk. The passenger in the accident airplane recalled that during takeoff, the airplane's nose snapped to the right and then pointed toward the ground. The pilot in the other airplane (which had not yet departed) observed the accident airplane take off and reported that when it was about 150 ft above the ground, the right wing dropped and simultaneously he heard the accident pilot say "whoa" over the radio. The airplane's nose continued to drop, and the airplane impacted the ground in a nose-low, near-vertical attitude. Examination of the airplane revealed that the left aileron control cable was separated from the eye fitting and thimble on the left aileron control cable turnbuckle. Further, the outboard left aileron control cable and the inboard right aileron control cable were improperly crimped. The improper crimping allowed the left aileron cable to pull through the swaged sleeve. As a result, the separation of the cable would have allowed the balance cable to become slack and the pilot would not have been able to control the roll of the airplane. Examination of maintenance records revealed that 20 years before the accident, the left wing was rebuilt and reskinned and the flap and aileron hardware were replaced. The entry did not specifically mention that the control cables were replaced. Additionally, 10 years before the accident, the aileron balance cable and rudder cables were tightened. The airplane received an annual inspection every year, during which no discrepancies were noted with the flight control systems.
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
- Loss of control in flight during initial climb defining event
The NTSB's findings
- cause Aircraft › Aircraft systems › Flight control system › Aileron control system › Fatigue/wear/corrosion
- factor Aircraft › Aircraft systems › Flight control system › Aileron control system › Inadequate inspection
- factor Personnel issues › Task performance › Inspection › Scheduled/routine inspection › Maintenance personnel
Pilot
- Certificate: commercial pilot
- Ratings: single-engine land; single-engine sea; instrument: airplane
- Flight time: 10,000 hours in all; 0 in this make and model
- Medical certificate: Class 3 (with waivers/limitations)
- Seat: frt
- Injury: fatal
Passenger
- Seat: rear
- Injury: serious injuries
The aircraft
- Airframe total time: 5,411.9 hours
- Last inspection: annual inspection, September 10, 2017
- Maximum gross weight: 1,750 lb
- Landing gear: fixed
- Engine: Lycoming O-320-B2B (piston); 5,412 hours total
The flight
- Departed from: NA Murphy ID at 3:15 pm
- Destination: BOI Boise ID
- Flight plan: none
Weather at the time
- Light: daylight
- Wind: from 310° at 7 knots, gusting 12
- Visibility: 10 statute miles
- Sky: overcast at 6,000 ft; clear
- Temperature: 45°F (7°C), dew point 41°F (5°C)
- Altimeter: 29.81 inHg
- Observation at 4:55 pm from KMAN, 48 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 | |||
| Passengers | 1 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
10 documents, released by the NTSB on October 9, 2020. 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 | Materials Laboratory Factual Report 18-100 | PDF, 8 pages | View Download |
| 2 | Record of Conversation (Ashley) | PDF, 1 page | View Download |
| 3 | Record of Conversation (Bublitz) | PDF, 2 pages | View Download |
| 4 | NTSB Airframe and Engine Report | PDF, 6 pages | View Download |
| 5 | Excerpt of Airplane Logbook | PDF, 2 pages | View Download |
| 6 | MS51844E Specifications for Sleeve Dimensions | PDF, 5 pages | View Download |
| 7 | FAA Advisory Circular Excerpt Ac 43.13-1B | PDF, 7 pages | View Download |
| 8 | Statement of Party Representatives to NTSB Investigation (Piper) | PDF, 1 page | View Download |
| 9 | Statement of Party Representatives to NTSB Investigation (Lycoming) | PDF, 1 page | View Download |
| 10 | Toxicological Report | PDF, 1 page | View Download |
The same docket at the NTSB · documents without a copy here are fetched from the NTSB when you open them.
Other NTSB records under N4393Z the same tail number, which may have belonged to a different aircraft at the time
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.