What is the lowest RVR minimum authorized for takeoff when RVR is available?

The lowest RVR (Runway Visual Range) minimum authorized for takeoff, when RVR is reported, is indeed 500 RVR. This standard is established in aviation regulation and reflects the minimum visibility required for a pilot to safely operate an aircraft during takeoff. A takeoff can be performed at this visibility level as it allows pilots to have sufficient distance in which to recognize runway markings, align with the runway centerline, and achieve a safe departure.

Operating at 500 RVR ensures that despite potentially challenging visibility conditions, pilots can maintain adequate situational awareness to execute a successful takeoff. Other values, such as 1000 RVR, 250 RVR, and 800 RVR, are higher than the minimum requirement and may apply under specific conditions or in relation to specific aircraft capabilities, but when RVR is available, 500 RVR is the established minimum for takeoff. This regulation helps to ensure the safety of flight operations in reduced visibility conditions.