What is the maximum tailwind component permitted for takeoff?

The correct answer is based on the aircraft's operational limits, which are established to ensure safe performance during takeoff. For many regional jets, including the CRJ550, the maximum permitted tailwind component for takeoff is typically set at 10 knots. This limitation is crucial because exceeding the maximum tailwind can adversely affect the aircraft's climb performance, control during the initial phase of flight, and the ability to achieve necessary takeoff speeds. Operating within this limit helps to ensure that the aircraft can safely gain altitude and maneuver following takeoff.

For the other choices, a maximum tailwind component exceeding 10 knots would generally compromise safety margins and performance metrics that are carefully calculated by manufacturers and regulatory authorities. For example, a valve set at 15 knots or higher may lead to insufficient lift-off performance, especially if the runway is short or if there are obstacles close to the departure end of the runway. Therefore, adhering to the 10-knot limit helps in maintaining aviation safety and performance standards.