Piper J4A N8501Z

Summary

On 30 May 2021 at about 14:55 local time, a Piper J4A registered N8501Z was involved in an accident near Omaha, Nebraska, United States. One person was on board and one had minor injuries. The aircraft was substantially damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

30 May 2021 at 14:55

Classification

Accident

Location

Omaha, Nebraska, United States

Nearest airport

North Omaha (3NO)

Coordinates

41.3696, -96.0222

Aircraft

Piper J4A

Registration

N8501Z

Category

Airplane

Year built

1940

Engines

1

Operator

Not recorded

Operating rule

Part 91: General Aviation

Purpose of flight

Personal

Phase of flight

Not recorded

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

CEN21LA242

1 person had minor injuries.

A total loss of engine power due to a blocked fuel tank cap vent hole, which resulted in fuel starvation. Contributing to the accident was the mechanic’s and the pilot’s inadequate inspections of the fuel tank cap.

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

Read the full NTSB narrative

During takeoff, the airplane traveled about three-quarters of the way down the runway and climbed to about 300 ft above ground level. The engine sputtered once and stopped producing power. The pilot switched the fuel selector from the forward fuel tank to the auxiliary fuel tank and unsuccessfully tried to restart the engine. The pilot maneuvered the airplane for a forced landing, and the airplane impacted the ground. The pilot reported that fuel was pouring into the cockpit after the airplane came to rest, and he quickly exited the airplane. The airplane sustained substantial damage to both wings and the fuselage. A postaccident examination revealed that the forward fuel tank cap was not the correct part for the airplane; the cap had an unknown part number etched on it with no manufacturer name displayed. The fuel tank cap appeared to be manufactured with a single vent hole and was equipped with two worn gaskets stacked under the cap. The lower gasket had multiple visible cracks present on both sides of it. The upper gasket was wrinkled and was displaced toward the vent hole, which blocked the venting capability of the fuel tank. For the accident model airplane, the sole source of venting for the forward fuel tank was through a vented fuel tank cap. The pilot reported that the forward fuel tank cap was on the airplane when he purchased it several years ago. The pilot did not have any knowledge of the origin or the background of the forward fuel tank cap. It is likely the engine sustained fuel starvation during the takeoff due to blockage of the forward fuel tank cap vent hole. Based on the available evidence, it could not be determined when the vent hole became blocked. The accident occurred 39 days and 2.3 flight hours after the most recent annual inspection. During the inspection, the mechanic should have observed the multiple visible cracks present on both sides of the lower gasket in the fuel tank cap. Further, during the preflight inspection, the pilot should have observed the multiple visible cracks present on both sides of the lower gasket in the fuel tank cap. Had the deficiencies with the fuel tank cap gasket been observed during the annual inspection or preflight, it is likely the fuel tank cap would have been replaced.

Quoted verbatim from the NTSB record.