Identify, Verify, Feather
“Identify, verify, feather” is a training framework for dealing with an engine failure in a multi-engine airplane. The exact actions, order and limitations are airplane-specific, so the approved checklist and instructor procedures always control. The framework is useful because it separates three different decisions that should not be rushed together.
Identify the failed engine
An engine failure usually creates yaw toward the failed side, roll tendencies, loss of performance and changes in engine indications. A classic memory aid is “dead foot, dead engine”: the foot not requiring rudder pressure is associated with the failed side. That is only an identification cue, not permission to secure an engine.
Verify before securing
Verification exists to prevent shutting down the operating engine. In training, pilots confirm that manipulating the suspected engine's control produces the expected response before committing to a shutdown. The specific control movement and exact sequence must match the airplane's approved procedure.
Why feathering matters
A windmilling propeller can create enormous drag. Feathering turns the blades toward a low-drag angle, reducing the aerodynamic penalty from the failed engine. That can make a major difference in single-engine climb capability and aircraft controllability.
Control first, then troubleshoot
Maintain control and follow the approved engine-failure procedure for the airplane. Identification and verification guard against securing the operating engine. This page is an explanation, not an emergency checklist.
Related concepts
Continue with zero sideslip, single-engine climb performance, VMC versus VYSE, and the multi-engine checkride hub.
FAA source
The FAA Airplane Flying Handbook covers engine-inoperative flight and multiengine procedures. Open the current FAA handbook.