Piper PA28R accident near Peoria, Arizona, May 29, 2012
On May 29, 2012 at about 4:30 pm local time, a Piper PA28R, registered N963WW, was substantially damaged in an accident during maneuvering (low-alt flying) near Peoria, Arizona (Pleasant Valley Airport). It was a flight test 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 for reasons that could not be determined because postaccident examination did not reveal any anomalies that would have precluded normal operation.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- May 29, 2012 · about 4:30 pm local time
- Place
- Peoria, Arizona · Pleasant Valley Airport · map
- Type
- Accident
- Injuries
- No one was hurt; 2 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Piper PA28R 201 · all PA28Rs on the register
- Registration
- N963WW · registry record · serial 2844023
- Damage
- Substantial damage
- Flight
- Flight test · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
At 8,500 feet, the designated pilot examiner instructed the commercial pilot to demonstrate steep spirals. The pilot configured the airplane by placing the mixture control to the FULL RICH position, entered the spiral maneuver, and cleared the engine every 180 degrees while in the turn. After the fourth spiral, the pilot attempted to make a simulated emergency landing, but when he observed that he was high, he put the airplane into a slip to lose altitude. When the examiner instructed the pilot to go around, the pilot advanced the throttle, but the engine did not respond. The pilot subsequently landed the airplane long, and it ran off the end of the runway. During the postaccident examination, the engine was run with no anomalies noted. The inspector subsequently discussed with the flight school’s chief flight instructor the procedure for setting the mixture control to the FULL RICH position at altitude before initiating a maneuver such as steep spirals. The chief instructor alluded to information provided by the engine manufacturer that the recommended procedure is to set the mixture to FULL RICH below 5,000 feet. After the accident, the chief instructor issued a company policy statement which read, “When leaned at altitude for flight, students and instructors should gradually enrichen the mixture throughout the descent, reaching full rich mixture while descending through 4,000 feet.” According to Service Instruction No. 1094D, issued by the engine manufacturer on March 25, 1994, relative to fuel mixture leaning procedures for all of the manufacturer's Opposed Series Engines, “For 5,000 feet density altitude and above or high ambient temperatures, roughness or reduction of power may occur at full rich mixture.” A representative for the engine manufacturer stated that the mixture setting during a low-power descent is not really a concern and that the mixture only needs to be adjusted when the engine power is required during takeoff, climb, and cruise. The engine representative added that if the pilot had put the mixture to full rich and descended, the engine would have been fine and should not quit. Therefore, while it may have been possible that the placement of the mixture to the FULL RICH position at altitude could have resulted in the power interruption at the lower altitude, there is no definitive evidence to support this position. The reason for the reported loss of engine power could not be determined.
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 engine power (total) during maneuvering (low-alt flying) defining event
- Loss of engine power (total) during emergency descent
- Runway excursion during landing (landing roll)
The NTSB's findings
- cause Not determined › Not determined › (general) › (general) › Unknown/Not determined
Pilot
- Certificate: private
- Ratings: single-engine land; instrument: airplane
- Flight time: 269 hours in all; 29 in this make and model; 91 in the last 90 days; 19 in the last 30 days; 169 as pilot in command
- Last flight review: March 28, 2012
- Medical certificate: Class 1 (without waivers/limitations)
- Seat: left
- Injury: no injuries
Pilot (unmanned)
- Certificate: airline transport pilot, flight instructor, flight engineer
- Ratings: multi-engine land; single-engine land; instructor: airplane multi-engine; instructor: airplane single-engine; instructor: instrument airplane; instrument: airplane
- Flight time: 17,400 hours in all; 18 in this make and model; 11 in the last 90 days; 10,400 as pilot in command; 2,800 on instruments
- Last flight review: May 20, 2012
- Medical certificate: Class 1 (without waivers/limitations)
- Seat: rgt
- Injury: no injuries
The aircraft
- Airframe total time: 7,282 hours
- Last inspection: annual inspection, April 2, 2012; 70 hours since
- Maximum gross weight: 2,750 lb
- Seats: 4
- Landing gear: retractable
- Engine: Lycoming IO-360 (piston); 0 hours total
- Operator: Westwind Aviation Inc.
The flight
- Departed from: DVT Phoenix AZ at 3:30 pm
- Destination: DVT Phoenix AZ
- Flight plan: none
- Runway 05R, 4,200 ft by 100 ft
- A second pilot was aboard
Weather at the time
- Light: daylight
- Wind: at 3 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 84°F (29°C), dew point 12°F (-11°C)
- Altimeter: 29.95 inHg
- Observation at 4:53 pm from DVT, 10 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight 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 N963WW 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.
