Boeing A75N1(PT17) N75016

Summary

On 26 May 2021 at about 21:30 local time, a Boeing A75N1(PT17) registered N75016, operated by One Slim Rabbit LLC, was involved in an accident near Hollister, California, United States. 2 people were on board and 2 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

26 May 2021 at 21:30

Classification

Accident

Location

Hollister, California, United States

Nearest airport

Frazier Lake Airpark (1C9)

Coordinates

36.9555, -121.4679

Aircraft

Boeing A75N1(PT17)

Registration

N75016

Category

Airplane

Year built

1942

Engines

1

Operator

One Slim Rabbit LLC

Operating rule

Part 91: General Aviation

Purpose of flight

Personal

Phase of flight

Not recorded

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

WPR21LA208

2 people had minor injuries.

The improper installation of a relief valve spring that was shorter than the standard spring length, which slowed the response of the propeller governor to change the pitch of the blades during climbout, resulting in a partial loss of power.

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

Read the full NTSB narrative

The airplane was climbing out shortly after takeoff when the pilot noticed that the engine rpm was decreasing, and that the airplane was not gaining altitude. The pilot added that, even with the decrease in engine rpm, the engine was still producing some engine power. The pilot-rated passenger stated that the airplane was not gaining or losing altitude and that he verified that the propeller, throttle, and mixture control levers were in the correct settings. The pilot decided to maneuver away from power lines and make a forced landing onto a field. Subsequently, the lower part of both wings impacted the ground and sustained substantial damage. A postaccident examined revealed that the propeller governor had a relief valve spring that was shorter in length than a standard relief valve spring. The shorter relief valve spring resulted in an internal governor pressure of 125 psi, which was less than the manufacturer’s setting of 180 to 200 psi. The lower internal pressure setting slowed the governor’s ability to make the immediate corrections in propeller blade pitch necessary to maintain the engine rpm during the climb out, which caused the engine to lose partial power.

Quoted verbatim from the NTSB record.