Gulfstream G IV N619A incident near Philadelphia, Pennsylvania

Probable cause

The flight crew’s misalignment of the airplane with a taxiway instead of the assigned runway, resulting in a low-altitude go-around late in the final approach and reduced separation with the airplanes on the taxiway.

NTSB analysis

Pegasus Elite Aviation flight 19 was on final approach to runway 35 at Philadelphia International Airport, Philadelphia, Pennsylvania. The airplane deviated from the runway 35 centerline about 2.4 miles from the runway 35 threshold and aligned with taxiway E shortly thereafter. The flight crew initiated a low-altitude go-around, arrested the airplane’s descent, and started to climb the airplane about 0.1 mile from the south end of taxiway E. The airplane flew past four airplanes that were on taxiway E.

The captain stated that he was flying a visual approach to runway 35 with the area navigation (RNAV) approach for backup. Both flight crewmembers stated that the RNAV needle showed that the airplane was centered during the approach. The captain stated that, as the flight proceeded inbound, the airport lights blended together, and he lost visual contact with the runway at a distance of about 1 to 2 miles out and at an altitude of 500 ft above ground level (agl). The first officer stated that he did not see the approach lights or the runway, and that the captain initiated the go-around 1 mile from the airport while the airplane was at 500 ft agl.

Flight data recorder (FDR) and Federal Aviation Administration (FAA) radar data showed that, during go-around procedure, the airplane moved to the right from aligned with the taxiway to between the taxiway and runway, and reached a minimum altitude of 125 ft agl when it was 0.1 mile from the runway 35 threshold, at which point the airplane stopped descending and began climbing. FAA radar data showed that the closest the incident airplane came to the first airplane it passed was about 200 ft vertically. The airplane then flew past the three other airplanes that were on taxiway E while continuing to climb.

The flight crewmembers initiated a low-altitude go-around because they did not recognize that the airplane was misaligned with the runway until late in the final approach. As a result, safety margins were severely reduced given the incident airplane’s proximity to the ground before the airplane began climbing and the minimal distance between the incident airplane and the airplanes on taxiway E.

The high-intensity runway lights (HIRLs) for runway 35 were on step 1, the same level as the taxiway lights. Both flight crewmembers reported that they called the air traffic control tower to request that the runway light setting be increased, but their request was not heard on the ATC audio recording. The reduced visual cues could have contributed to the flight crew’s delay in identifying the airplane’s misalignment with the intended landing surface. However, sufficient visual cues should have been available to the flight crew to indicate the need for a go-around earlier in the approach, including the presence of four airplanes on a taxiway that was 400 ft to the left of runway 35.

Text from the NTSB. Open the NTSB docket for DCA18IA265 for the full record.