EMERGENCY EXTENSION PROC USED TO LOWER NOSE GEAR.

Date: 1988-09 · Aircraft: Medium Large Transport; Low Wing; 2 Turbojet Eng · Phase: approach

Anomalies: aircraft-equipment-problem-critical

Synopsis

EMERGENCY EXTENSION PROC USED TO LOWER NOSE GEAR.

Narrative

LNDG GEAR WAS LOWERED IN PREPARATION FOR LNDG. THE MAIN GEAR WENT DOWN AND LOCKED; HOWEVER THE NOSE GEAR DID NOT COME OUT OF THE UP LOCKS. THE GEAR WAS RECYCLED AFTER A CHK OF HYD PRESSURE AND QUANTITY WHICH WAS FOUND TO BE NORMAL. STILL WITH NO NOSE GEAR DOWN A GO AROUND WAS EXECUTED. ATC VECTORED THE FLT OUT FOR FURTHER EVALUATION OF THE PROB. AFTER READING THE PROCS THE EMER GEAR EXTENSION PROC WAS USED AND THE NOSE GEAR DID COME DOWN AND LOCK. USING THE EMER GEAR EXTENSION PROC REMOVES HYD PRESSURE FROM THE GEAR SYS THUS THE MAIN GEAR DOORS REMAIN OPEN AND ARE SUBJECT TO DAMAGE UPON LNDG. HYD PRESSURE WAS NOT RESTORED TO THE SYS BECAUSE I AND THE F/O FELT IT WOULD BE BEST TO LEAVE THE GEAR AS IT WAS SINCE IT WAS NOW DOWN AND LOCKED. WE DID NOT KNOW AT THAT TIME WHAT THE PROB WAS OR WHAT MIGHT HAPPEN IF PRESSURE WAS REAPPLIED TO A POSSIBLY BROKEN GEAR. THE POSSIBLY BROKEN GEAR CAME TO MIND BECAUSE OF AN UNUSUAL POP HEARD EARLIER. WHEN TAXIING OUT OF OUR PARKING SPOT EARLIER; I WAS TURNING THE ACFT TO THE RIGHT WHEN AN UNUSUAL POP OCCURRED. WE COMMENTED ABOUT THIS; BUT WITH NO CHANGE NOTED IN THE ACFT HANDLING OR HYD PRESSURE OR QUANTITY WE DECIDED IT MUST BE ONE OF THE CREAKS AND CRACKS THAT ACFT MAKE SOMETIMES DURING TAXIING. ON POST-FLT INSPECTION OF THE ACFT WE WERE UNABLE TO SEE ANYTHING UNUSUAL. THE F/A'S WERE KEPT INFORMED OF THE SITUATION. I ALSO INFORMED THE PAX OF THE SITUATION AND FINALLY LET THEM KNOW THAT WE HAD BEEN ABLE TO LOWER THE LNDG GEAR BY AN ALTERNATE METHOD. DISPATCH WAS ADVISED OF OUR SITUATION DURING THE FLT. THEY WERE INFORMED SO WE COULD HAVE MAINT MEET THE ACFT ON THE RWY AFTER LNDG. MAINT DID ASSESS THE CONDITION OF THE ACFT AFTER LNDG. THE MAIN GEAR DOORS WERE SLIGHTLY DAMAGED BY DRAGGING ON THE RWY. NO OTHER DAMAGE WAS APPARENT. NO EVAC WAS NEEDED AND AFTER MAINT CLOSED THE MAIN GEAR DOORS AND PINNED THE GEAR IN THE DOWN POS WE TAXIED TO THE RAMP. THE CRASH EQUIP HAD BEEN REQUESTED AND WAS OUT FOR PRECAUTIONARY MEASURES. I ALSO REQUESTED THAT 1 TRUCK FOLLOW US INTO THE RAMP IN THE EVENT OF OTHER DEVELOPMENTS. THE FLT ENDED WITH NO OTHER INCIDENTS. COMMENTS: THAT WAS A VERY BUSY 15 MINS. DURING THAT TIME WE HAD TO KEEP THE F/A'S INFORMED; THE PAX INFORMED; ATC INFORMED; THE COMPANY INFORMED AND FLY THE PLANE. I HAVE FLOWN ON 2-CREW AND 3-CREW ACFT AND THINK A 2-CREW ACFT BORDERS ON MARGINAL SAFETY BECAUSE OF THE HEAVY WORKLOAD WHEN IN AN EMER SITUATION. I USED TO HAVE MIXED FEELINGS OF THE 2-M CREW; BUT TODAY I FEEL THE 3-M CREW IS NEEDED. THIS ENTIRE SITUATION POSSIBLY COULD HAVE BEEN AVOIDED IF THE ACFT WAS UNDER A CYCLE CHANGE OF PARTS INSTEAD OF ON CONDITION. I SAY THIS BECAUSE THE MAINT SUPVR COMMENTED TO ME AFTER THE FLT THAT IT WAS PROBABLY THE TELEFLEX CABLE THAT BROKE NOT ALLOWING THE NOSE GEAR TO EXTEND. HE ALSO SAID THIS IS A COMMON FAILURE.

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