Basic Reporting Data, 7. Werlich also noted the location of the B-52: “VISUAL SIGHTING DATA: 3200 FEET MSL, 335 DEGREES MH [Magnetic Heading], APPROXIMATELY 180 IAS” (2). In a personal communication with this author, Runyon explained: GCA is a ground-controlled approach including precision and surveillance approaches. The precision approach provides corrections right and left and above and below a predetermined glide path to the runway. During surveillance approach, the ground controller only gives heading corrections and it is up to the aircrew to determine their own rate of descent.