What happened
On July 7, 2016, a Delta Air Lines Airbus A320-211, registration N333NW, was conducting a scheduled passenger flight from Minneapolis St. Paul International Airport to Rapid City Regional Airport (RAP). During the approach to the Rapid City area, the flight crew was managing a high and fast descent. While the crew had briefed for an ILS approach to runway 32, they also prepared for an RNAV/GPS 14 approach due to shifting winds.
As the aircraft descended through 12,000 feet, air traffic controllers noted the airplane was high and fast for the planned visual approach. The captain, while demonstrating Flight Management System (FMS) configuration techniques to the first officer, called for the landing gear and flaps. At this time, the aircraft was positioned east of Ellsworth Air Force Base (RCA), with RAP located to the south-southwest.
After being vectored for a downwind leg, the crew requested an extended downwind to manage their altitude. Upon receiving a visual approach clearance for runway 14 at RAP, the controller specifically advised the crew to use caution for Ellsworth Air Force Base, located six miles northwest of Rapid City Regional. The crew reported mishearing this warning as a standard position advisory.
As the aircraft turned onto the base leg, the captain selected a direct radial to the ZUDIM intersection. The crew subsequently switched off the autopilot and flight directors. The aircraft began a rapid descent from 4,600 feet, eventually descending at approximately 1,200 feet per minute. The crew realized they were approaching the wrong runway just as the thrust levers were retarded to idle. The aircraft landed on runway 13 at RCA. The landing was described as uneventful, and there were no injuries.
Findings
- The flight crew misidentified the intended landing runway.
- The crew did not use all available navigation information to verify their position.
- The crew's decision to disengage the autopilot and flight directors removed potential positional cues.
- The crew misheard the air traffic controller's warning regarding the proximity of Ellsworth Air Force Base.
- The aircraft was at an excessive altitude, necessitating an extended downwind leg that contributed to the confusion.
- The crew had little to no prior experience flying into either RAP or RCA.