What are the critical engine failure and takeoff safety speeds for Operating Conditions R-4?

The critical engine failure and takeoff safety speeds are essential for safe aircraft operations during takeoff, particularly under conditions that may lead to an engine failure. For Operating Conditions R-4, the correct values of these speeds are 123 knots for critical engine failure speed and 134 knots for takeoff safety speed.

Understanding these speeds helps pilots and dispatchers determine the minimum required performance necessary to maintain safety margins in the event of an engine failure during the critical phase of takeoff. The critical engine failure speed represents the speed below which the aircraft may not be able to maintain controlled flight with one engine inoperative, while the takeoff safety speed provides a buffer above this to ensure that the aircraft can safely accelerate and gain altitude.

These speeds are carefully calculated based on aircraft performance data, weight, and weather conditions, among other factors. Therefore, option A reflects the correct numbers necessary to ensure compliance with safety standards and effective operation during takeoff phases.