What is the proper configuration and airspeed for a single-engine ILS final approach?

In a single-engine ILS final approach, the correct configuration is crucial for maintaining both safety and performance. The proper setup typically involves the landing gear being down, which is standard for any landing phase to provide drag and stability. The configuration of the flaps plays a significant role in generating lift at lower airspeeds.

For the specific airspeed, using VREF plus an additional 10 knots ensures you have a comfortable margin above the stall speed, which is particularly important during single-engine operations where performance can be more affected by drag and lift considerations. VREF represents the reference landing speed for an aircraft in a landing configuration, and adding 10 knots allows for a buffer that accounts for any potential reductions in performance due to the single-engine condition.

This configuration not only stabilizes the aircraft on approach but also ensures adequate control authority, which is critically important when flying with an engine out. It balances safety with performance demands for a stable descent on an ILS approach. Thus, landing gear down, flaps set at 10 degrees, and flying at VREF + 10 KIAS represents the best practice for this maneuver.