Contrary to existing airports in the suburbs, a vertiport is located in a complex urban area and has space limitations. Precision landing technology at a vertiport is essential for safe urban air mobility (UAM) operations in limited spaces. The U.S. Federal Aviation Administration (FAA) has recently released a symbol design for vertiport identification. However, research on the precision landing of a UAM vehicle using this symbol is still insufficient. We propose a vision-based system for detecting the FAA vertiport marking to ensure precision landing on a vertiport. After the existing fiducial marker detectors have been benchmarked, we establish a methodology that recognizes the vertiport marking, estimates the relative position and attitude through transformation, and visualizes the pose estimation results to instruments similar to the instrument landing system. Marking detection and pose estimation are validated experimentally by using cameras and drone flight tests. The results show the applicability of the proposed approach under the operating conditions for UAM.