Cessna 180 N1621C

Summary

On 2 October 2009 at about 19:40 local time, a Cessna 180 registered N1621C, operated by William Gonce, was involved in an accident near Mitchell, Oregon, United States. 3 people were on board and one was seriously injured, 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

2 October 2009 at 19:40

Classification

Accident

Location

Mitchell, Oregon, United States

Coordinates

44.3531, -119.8792

Aircraft

Cessna 180

Registration

N1621C

Category

Airplane

Engines

1

Operator

William Gonce

Operating rule

Part 91: General Aviation

Purpose of flight

Personal

Phase of flight

Not recorded

Route

Pistol Creek → Redmond

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

WPR10LA001

1 person was seriously injured.

The pilot’s lack of understanding of the airplane’s fuel system, which resulted in a loss of engine power due to fuel exhaustion.

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

Read the full NTSB narrative

The single engine airplane experienced a loss of engine power during flight and the pilot performed a forced landing in rugged terrain. Examination of the airplane wreckage revealed minimal evidence of fuel. The airplane had a modified fuel tank system through a supplemental type certificate (STC). The STC changed the fuel capacity of the two fuel tanks from 30 gallons to 28.2 gallons each. The installation information for the STC noted that to determine the usable fuel for the airplane, the airplane’s type certificate data sheet (TCDS) should be referenced and the unusable fuel amount listed therein should be subtracted from the new total fuel capacity. The TCDS for the airplane stated that 5 gallons of fuel were unusable, which made the new total usable fuel capacity on the airplane 51.4 gallons. As a part of the STC, the airplane flight manual (AFM) and the fuel selector valve placard were to be updated with the revised usable fuel quantity. This action was noted on the FAA Form 337 for the STC installation. The pilot had purchased the airplane several years prior to the accident and the previous owner told him that all of the fuel (56.4 gallons) was usable. The pilot reported that there was no AFM supplement for the STC included in his paperwork, and that he did not ever look at the quantities indicated on the fuel selector valve placard in the cockpit due to its location between the seats. Examination of the recovered airframe and engine components revealed no evidence of preimpact mechanical malfunction.

Quoted verbatim from the NTSB record.