Which of the following steps is critical during engine failure after takeoff?

Identifying the failed engine immediately is critical during an engine failure after takeoff because swift and accurate identification allows the pilot to manage the aircraft's performance and ensure the safety of all onboard. In a multi-engine aircraft, an engine failure can significantly affect control and performance; therefore, the pilot must quickly ascertain which engine has failed to apply the appropriate emergency procedures.

Once the failed engine is identified, the pilot can take necessary actions to maintain control, such as adjusting power on the operating engine, configuring the aircraft for the appropriate climb performance, and managing any asymmetrical thrust that might affect the aircraft's handling characteristics. This process includes the immediate actions of maintaining directional control through the use of ailerons and rudder, as well as configuring flaps and landing gear properly.

Checking fuel levels or communicating with a navigator may be important in the broader context of flight operation or pre-takeoff checks, but they are not as critical during the immediate response to engine failure. Additionally, ignoring altitude changes during this emergency scenario is unsafe and could lead to a loss of control. Therefore, prompt recognition of the failed engine is fundamental for effective and safe maneuvering post-departure.