AN ACR MLG LOST MOST OF ITS HYD SYS.

Date: 1993-12 · Aircraft: Medium Large Transport; Low Wing; 2 Turbojet Eng

Anomalies: aircraft-equipment-problem-critical

Synopsis

AN ACR MLG LOST MOST OF ITS HYD SYS.

Narrative

IN CRUISE FLT; THE MASTER CAUTION ANNUNCIATOR ILLUMINATED FOR SYS 'A' HYD LOW PRESSURE FOR THE #1 ENG DRIVEN PUMP. WE FOLLOWED THE PROCS IN THE PLT'S HANDBOOK AND TURNED THE SYS 'A' PUMP SWITCH TO OFF. THE HYD FLUID QUANTITY GAUGE INDICATED FULL. UPON DSCNT; THE MASTER CAUTION ANNUNCIATED AGAIN SHOWING LOW HYD PRESSURE ON THE #2 ENG DRIVEN PUMP FOR THE 'A' HYD SYS. WE FOLLOWED THE SAME PROC AS ABOVE; DECLARED AN EMER; AND CHKED THE SYS 'A' HYD GAUGE WHICH STILL INDICATED FULL. WE PROCEEDED WITH THE LOSS OF SYS 'A' HYD PROC IN THE PLT'S HANDBOOK. AS WE EXTENDED THE FLAPS AND GEAR BY ALTERNATE MEANS; THE MASTER CAUTION ANNUNCIATED AGAIN FOR SYS HYDS AND WE NOTICED ERRATIC N1 AND FUEL FLOW ON THE #2 ENG. AT THIS TIME WE REQUESTED A SHORTER FINAL. ON FINAL; THE CAPT SAID THE AIRPLANE FELT AS THOUGH IT WANTED TO ROLL TO THE R AT VREF 15; SO WE INCREASED AIRSPD. WE FELT THE TENDENCY TO ROLL MIGHT BE CAUSED BY A SPOILER FLUTTER. LNDG WAS UNEVENTFUL WITH THE SPD BRAKE AND REVERSERS DEPLOYING AS EXPECTED. AFTER LNDG; WE NOTICED A LOW QUANTITY LIGHT FOR THE STANDBY HYD SYS WHICH WOULD EXPLAIN THE THIRD ILLUMINATION OF THE MASTER CAUTION LIGHT. THE ACFT WAS TOWED TO THE GATE. AT THE GATE; IT WAS DISCOVERED THAT THE SYS 'A' HYD QUANTITY GAUGE WAS FAULTY AND THE #2 HYD PUMP WAS LEAKING FLUID.

Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.