Piper PA28 N4403Z

Summary

On 14 September 2019 at about 00:30 local time, a Piper PA28 registered N4403Z, operated by Cae Oxford Aviation Academy Phoenix Inc, was involved in an accident near Marana, Arizona, United States. 4 people were on board and nobody was injured. The aircraft was substantially damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

14 September 2019 at 00:30

Classification

Accident

Location

Marana, Arizona, United States

Nearest airport

Marana Regional Airport (AVQ)

Coordinates

32.4039, -111.2197

Aircraft

Piper PA28

Registration

N4403Z

Category

Airplane

Year built

2013

Engines

1

Operator

Cae Oxford Aviation Academy Phoenix Inc

Operating rule

Part 91: General Aviation

Purpose of flight

Instructional

Phase of flight

Not recorded

Route

Unknown → Mesa

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

WPR19LA259

Nobody was injured.

Excessive fuel pressure and temperature throughout the fuel system due to heat soaking, which resulted in an engine fire during engine start.

Quoted verbatim from the NTSB record. This site does not paraphrase or interpret it.

Read the full NTSB narrative

During engine start about 30 minutes following the previous shutdown, the engine caught fire, which resulted in substantial damage to the airplane. The operator reported that six of their airplanes experienced flooding and subsequent fires during the engine start process within the previous 6 months. The airplanes that experienced flooding and fires had all previously flown and been parked between 5 and 28 minutes before the engines were restarted and the flooding occurred. During these events, the daily average temperatures were between 85° and 98°F. Testing conducted to simulate the conditions of the engine fire events revealed that, in the minutes following engine shutdown, the temperature of the fuel system components and fuel pressure to the carburetor would rise, most likely as a result of heat soaking from the combination of the hot engine and high outside air temperature. The tests showed that during the engine restart, about 6 to 12 ounces of fuel and vapor emanated from the carburetor intakes. During some of the tests, a whistling sound was heard originating from the carburetor inlet, which is likely from the buildup of fuel vapor as a result of the heat soaking and escaping through the internal passages of the carburetor before exiting out the carburetor intake. The carburetor from the accident airplane was disassembled, and the accelerator pump needle valve showed wear at the valve contact area. This wear was likely a result of the high fuel pressure vapor and fuel escaping past the valve, causing it to chatter excessively. The operator had experienced recent growth in its student population, which resulted in increased frequency of flights during the day. This most likely prevented the engine and fuel system from cooling between flights.

Quoted verbatim from the NTSB record.