Sharp CORBEN BABY ACE D N794CH

Summary

On 13 June 2003 at about 18:30 local time, a Sharp CORBEN BABY ACE D registered N794CH was involved in an accident near Wamsutter, Wyoming, 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

13 June 2003 at 18:30

Classification

Accident

Location

Wamsutter, Wyoming, United States

Coordinates

41.8056, -107.1997

Aircraft

Sharp CORBEN BABY ACE D

Registration

N794CH

Category

Airplane

Engines

1

Operator

Not recorded

Operating rule

Part 91: General Aviation

Purpose of flight

Ferry

Phase of flight

Not recorded

Route

Rock Springs → Rawlins

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

DEN03LA153

1 person had minor injuries.

A loss of engine power due to carburetor icing. Contributing factors were weather conditions conducive to carburetor icing and unsuitable terrain available on which to make a forced landing.

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

Read the full NTSB narrative

The airplane was being ferried to its new owner. The pilot said he was cruising at 8,000 feet msl (1,000 feet agl), using a power setting of 2,400 rpm with the mixture leaned "for altitude." About 1 hour after takeoff, the engine began "sputtering and backfiring." Engine power dropped from 2,400 rpm to approximately 1,000 to 1,100 rpm. Unable to restore power, the pilot made a forced landing on rough, uneven terrain. During the landing roll, the airplane struck a hole and nosed over, coming to rest inverted. The accident site was at an elevation of 6,955 feet msl. The pilot told a sheriff's deputy that "it was either engine failure or [the] carburetor iced up." Temperature and dew point recorded at an automated weather observation station (AWOS) station, located 48 miles east of the accident site, were 4 degrees and 0 degrees C., respectively. According to the Carburetor Icing Probability Chart, the temperature and dew point correspond to "serious icing at cruise power." The computed relative humidity was 76 percent. The pilot said he had had "carburetor ice before and the onset was always a gradual onset of power loss requiring changes in the throttle setting until ice was recognized. This was NOT the case in this incident as the power loss was instant and no actions affected it after they were tried." According to FAA's Flight Training Handbook, the onset of ice may be subtle or sudden, particularly if ice forms on the carburetor jets, because it "tends to choke off the flow of air and reduce the power output, or even prevent the engine from operating." The engine was functionally tested to 2,100 rpm, and no discrepancies were noted. Additional power output was not possible due to the intake manifold being crushed during the accident.

Quoted verbatim from the NTSB record.