Gulfstream 150 N373ML accident near San Juan, Puerto Rico

Probable cause

The pilot’s loss of control during landing on a wet runway after encountering standing water.

NTSB analysis

The airplane approached the destination airport at night, with rain showers in the area and the runway reported as wet. The pilot-in-command (PIC) stated that the airplane touched down “close to” the computed reference speed of 122 knots and “in the vicinity” of the 1,000 ft marker of the runway. At touchdown, the thrust reversers were deployed, and as the airplane decelerated through 70 knots, the PIC noticed standing water on the runway ahead. As the airplane encountered the standing water, with about 1,000 ft of runway remaining, it yawed to the left, then to the right, and departed the runway and struck a fence, sustaining substantial damage to the right wing.

According to a Federal Aviation Administration inspector, the airport had a history of standing water forming on the runway due to poor drainage over the previous 2 years, which resulted in reports of poor braking performance.

Data from the airplane manufacturer indicated that, for the reported landing weight and weather conditions, the airplane required a landing distance of 3,620 ft on a wet runway and 4,100 ft on a contaminated runway (standing water). The landing distance available was 5,126 ft. Although the precise touchdown location and landing speed could not be determined, the manufacturer’s data suggest that the airplane could have stopped prior to reaching the 1,000 ft remaining location on the landing runway.

Text from the NTSB. Open the NTSB docket for ERA20LA221 for the full record.