Background
A certificated commercial pilot, who was also an Alaska State Trooper, departed from a remote lake in a float-equipped airplane. The airplane was the second of two in a flight. The first airplane had already departed. The accident airplane failed to arrive at its intended destination, prompting the first pilot to initiate an aerial search. The wreckage was discovered approximately one-quarter mile southeast of the departure lake.
Conversation About Fuel Valve Operation
The first pilot recalled a conversation with the accident pilot about the Cub Crafters main fuel valve installed in the accident airplane. The accident pilot commented that he was not flying the airplane normally assigned to him, which had the original Piper main fuel tank selector valve. The accident pilot expressed uncertainty about whether the fuel selector valve should be operated in the BOTH position or the LEFT or RIGHT positions.
Placard and Fuel Selector Position
The FAA-approved Cub Crafters STC requires a placard above the main fuel valve stating: "TAKE OFF AND LANDING ON BOTH ONLY." The accident airplane had this placard installed. During an on-scene inspection, the fuel selector valve was found selected to the LEFT fuel tank setting, and the left fuel tank was empty.
Differences Training
A review of the State of Alaska, Department of Public Safety's "aircraft manual," which outlines general operating policies and standards, disclosed that there were no provisions for differences training regarding the Cub Crafters fuel system.