PIPER PA 28-161 near El Cajon, CA — 2017-09-17

Probable cause

A partial loss of engine power due to the formation of carburetor ice during descent for landing. Contributing to the accident was the pilot’s failure to apply carburetor heat.

NTSB narrative

The commercial pilot reported that he and the pilot-rated passenger returned to the airport to practice touch-and-go landings after a local flight. The first two landings were uneventful. While on the downwind leg of the traffic pattern for the third landing, the pilot reduced engine power and started to descend the airplane. After turning base, the pilot increased power, but the engine did not respond and remained at idle. There was no change in engine noise and the engine was not running rough. The pilot manipulated the throttle and primer several times, but the engine did not respond, and the pilot elected to land the airplane on a nearby road. During the descent, the airplane struck powerlines and a tree before it impacted the road and slid to a stop. A postaccident engine examination did not reveal any anomalies that would have precluded normal operation. A review of the carburetor icing probability chart revealed that the airplane was operating in conditions favorable to the formation of serious carburetor icing at glide power. In addition, on-scene photographs revealed that the carburetor heat lever was in the off position; therefore, it is likely that carburetor ice accumulated during the descent, which resulted in a partial loss of engine power.

Analysis

Primary failure mode

Engine power loss

First missed decision gate

Pilot could have applied carburetor heat before engine power loss.

NTSB coding

• Loss of engine power (partial) · Approach-VFR pattern base
• Carburetor Icing Conditions

Evidence available

• Photos
• 4 docket documents

Docket documents4

• FAA Special Airworthiness Information Bulletin - Carburetor Icing Preventionform
• Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1form
• Engine Examination Observationsother
• On Scene Photo of the Carburetor Heat Lever Position - Courtesy of the FAAphotos

Related mishaps

• TAYLORCRAFT AVIATION CORP F19

  2022-05-17 · Anchorage, AK

• Piper PA34

  2020-08-18 · Groton, CT

• ZENITH STOL CH701

  2019-11-29 · Byron, CA

• LUSCOMBE 8A

  2017-06-03 · Rexberg, ID

• ENSTROM TH-180

  2016-02-12 · Menominee, MI

• PIPER PA 28-140

  2015-11-25 · Wickenburg, AZ