Piper PA-44-180 N2083D accident near Shakopee, Minnesota

Probable cause

The pilots’ failure to apply carburetor heat during the descent, which resulted in a loss of power on both engines due to carburetor ice.

NTSB analysis

One of the pilots, a flight instructor, was recently hired to instruct in the airplane and was receiving a check out flight from the assistant chief flight instructor. The pilots reported that they were preparing to enter the traffic pattern, so they began a descent from their cruising altitude of about 5,500 ft msl to 1,000 ft msl. About three miles from the airport, both engines on the multi-engine airplane began to run rough. Shortly thereafter, both engines lost all power. Despite the pilots advancing the propellers, mixtures, and throttles to their full forward position, engine power was not restored. The airplane continued to descend, and the pilots performed an off-airport landing onto a field. One of the pilots stated that they did not perform an emergency checklist because there was no checklist for a dual engine failure. Also, due to their proximity to the ground, they did not have time to perform an emergency checklist.

The airplane sustained substantial damage to the fuselage and both wings. A postaccident examination revealed that there were about 25 gallons of fuel in each nacelle, and both fuel selectors were in the “ON” position. The carburetor heat for each engine was in the “OFF” position. Examination of the engines and fuel system did not reveal any mechanical anomalies or failures that would have precluded normal operation.

The recorded temperature and dew point near the accident site were conducive to “serious icing” at glide power settings. The pilot operating handbook for the airplane stated that carburetor heat should be used “as required” during approach and landing or if engine roughness occurs. Based on this information, it is likely that carburetor ice formed while the throttles were retarded during the descent which resulted in the initial engine roughness and subsequent loss of engine power due to carburetor ice.

Text from the NTSB. Open the NTSB docket for CEN24LA360 for the full record.