Luscombe 8A N72066 accident near Longview, Texas

Probable cause

The pilot's failure to use carburetor heat for takeoff, which resulted in an interruption of continuous fuel flow to the engine and a loss of engine power during climb. Also causal was the lack of required placarding warning of the need to use full carburetor heat on takeoff and landing.

NTSB analysis

The commercial pilot departed on the personal flight with about half fuel. During the departure climb, the airplane experienced a loss of engine power. The pilot subsequently performed a forced landing to a field, and, during touchdown, the airplane nosed over and impacted the ground. Postaccident examination of the airplane revealed no evidence of mechanical malfunctions or failures that would have precluded normal engine operation. The pilot reported that he did not use carburetor heat during the takeoff. The use of full carburetor heat during takeoff and landing was stipulated by the airplane's type certificate data sheet, which indicated that a placard is required stating, "Full carburetor air heat required for takeoff and landing." However, the accident airplane did not have that placard installed.

Further, a special airworthiness information bulletin (SAIB) applicable to this airplane configuration noted the need for procedures to prevent the possible loss of power on takeoff and climb and stated that flight testing revealed that fuel flow could be interrupted from the fuselage-mounted tank as a result of acceleration and higher pitch attitudes commonly encountered in takeoff and climb. The SAIB stated that the use of full carburetor heat on takeoff is unconventional yet necessary to ensure continuous fuel flow to the engine. Thus, the pilot's failure to use carburetor heat resulted in the loss of engine power.

Text from the NTSB. Open the NTSB docket for CEN18LA209 for the full record.