Beijing Capital International Airport is one of the busiest hub airports in the world, but its capacity is limited. Reducing the minimum radar interval during instrument approaches would be feasible to increase capacity. The airport has three parallel runways; the distance between runways 36L/18R and 01/19 is 3.485 km. Currently, because there is no final monitoring seat, the dependent parallel instrument approach mode is adopted on the two runways; approaching aircraft must maintain a 4 km safety separation. This paper focuses on whether the 4 km radar safety separation for parallel instrument approaches could be reduced to 3.485 km without the final monitoring. This would mean implementing independent instrument approach operations between the two runways. To consider this, a new collision risk model based on position error probability and aircraft kinematics is proposed. A test program to acquire data on controllers’ reaction times in abnormal situations was designed and implemented over 10 days by the North China Air Traffic Management Bureau (ATMB). Furthermore, six months of radar trajectory data was collected at the airport. This was analyzed and processed to obtain the position error, speed, and other parameters required for the calculation of the collision risk model. The results show that the independent instrument approach operations between runways 36L/18R and 01/19 would be feasible the within safety target level set by the International Civil Aviation Organization (ICO). Based on the theoretical research results, the North China ATCB implemented independent instrument approaches between runways 36L/18R and 01/19 on December 25, 2018; it has operated safely since.