NTSB Factual Report

On January 21, 2005, at 1247 central standard time, a Sabre 40 twin turbo-jet airplane, Mexican registration XB-JGI, was substantially damaged during a ground collision with a parked airplane, following a reported loss of hydraulic pressure, while taxiing at the San Antonio International Airport (SAT), near San Antonio, Texas. The airline transport pilot and the commercial pilot were not injured. Visual meteorological conditions prevailed and an instrument flight rules flight plan was filed for the international flight conducted under 14 Code of Federal Regulations Part 91. The flight intended to depart from SAT at the time of the accident, with Toluca, Mexico, as its intended destination.

In a written statement, the 5,000-hour Mexican commercial pilot reported that after starting the right engine and completing a pre-taxi checklist on the ramp, he noted that all of the indications given by the instruments were normal. The flight was then cleared to taxi, so he turned the steering control on and advanced the power. The airplane moved straight ahead, and the pilot attempted to make a left turn. At that time the pilot realized his inputs to steer the airplane were ineffective. The airplane continued straight ahead. The pilot attempted to stop the airplane by applying pressure to the brakes and then used the emergency brake, but these actions were ineffective as well. The airplane continued forward and passed between two aircraft that were parked on the ramp, striking a parked Pilatus PC-12 airplane on its left with the left wing tip. The pilots then shut down the right engine, and the airplane continued in its forward momentum until it finally came to a complete stop.

The engine thrust reversers on the airplane had undergone maintenance at Toluca, Mexico, prior to the accident. The maintenance manual for the Sabre 40 airplane states, "An operational test of the hydraulic power system must be performed if a unit has been replaced, if adjustments have been made to any unit, or if hydraulic lines have been disconnected. The test must be thorough enough to ensure that the system is free of hydraulic leaks and that no malfunction could occur because of improper maintenance." The manual goes on to state, "Because of allowable indication error in the hydraulic pressure indicating system, the pressure on the gauge may not be the actual system pressure. For this reason, the indication error of the hydraulic pressure gauge and pressure transmitter should be known, if these instruments are used to determine the serviceability of hydraulic units."

According to a Federal Aviation Administration (FAA) inspector, who responded to the accident site, there was structural damage to left wing of the Sabre 40, as well as structural damage to the left rear fuselage and left wing of the Pilatus PC-12. Examination of the Sabre 40 by the FAA inspector revealed that the hydraulic fluid reservoir was empty, and the cockpit hydraulic pressure gauges indicated 2,000 pounds per square inch (psi).

A representative of the DGAC of Mexico examined the airplane on February 21, 2005. The examination found air in the hydraulic system. Hydraulic fluid was added to the system, and an operational check of the airplane's two separate hydraulic pumps was performed, which revealed no anomalies.

At 1253, the automated weather observing system at SAT reported wind from 220 degrees at 5 knots, 10 statute miles visibility, few clouds at 14,000 feet, overcast at 25,000 feet, temperature 71 degrees Fahrenheit, dew point 55 degrees Fahrenheit, and a barometric pressure setting of 30.00 inches of Mercury.

NTSB Probable Cause

The failure of the aircraft hydraulic system as result of improper maintenance by company maintenance personnel.