Narrative:

In sum: the reporting first officer was on his IOE in the MD11. The captain was a senior check pilot. There were 2 relief fos, with lots of experience, in the jumpseats. All anti-ice was turned on for descent. All 3 engines showed 'select fadec alternate' at different times disabling the autothrottles. 'Select elevator feel manual' and 'select flap limit' were flashing on and off. The icing turned into heavy rain. There was airframe buffeting as well as turbulence and roll control problems. 'Windshear detect fail' started blinking on and off along with the other warnings. Autoplt #2 was placarded inoperative and autoplt #1 disconnected 'maybe 10 times during approach.' crew made a missed approach and returned to VOR with improving WX. On second approach, ILS looked stable with some buffeting and nose attitude lower than normal. ATCT wind for runway 11 was 170 degrees/16 KTS. Captain attempted to flare at 50 ft, then again at 20 ft radio altimeter, then forced it onto the runway, past touchdown zone, and 'stood on the brakes.' reversers were delayed about 7 seconds because there were no fadecs. The aircraft went off the end of the runway about 100 yards into mud. The captain swerved to miss an antenna. 2L slide was deployed but not used. There was no fire or injuries. The reporter recommends: 50 degree flap lndgs when runway wet or tailwind (other acrs do this), fix runway, compare IRS ground speed to IAS when a discrepancy is suspected, put most experienced people in seats when the going gets tough, provide more alternate fuel for a wider choice of alternates, etc. Callback conversation with reporter revealed the following information: the reporter flew into saez in the middle of an immense storm, the '100 yr rain.' there had been no report from any ground source of the severity of the storm. This air carrier has had 3 instances similar to this instrument problem, apparently the only air carrier to do so. Apparently the entire problem was caused by 'lime deposits' that had clogged the static port drains. This caused the static ports to be unreliable causing the cadcs to shut themselves off and on. As the fadecs get information from the cadcs, they too became unreliable and the EICAS commanded them to be shut off. Without fadecs, it takes 7 seconds for manual actuation of the reversers and there are no autothrottles. The clogged static ports caused the altimeters to read 150 ft high. Fortunately, the land at the airport is flat and the radio altimeters worked properly and the aircraft had visual runway contact. The captain immediately jumped on the brakes after landing. When the reporting first officer also got on them, 'the anti-skid was going nuts!' the #3 engine was damaged by mud when the captain swerved to miss an antenna. This was the only damage. There was evidence of hydroplaning on the tires. The reporter went out to the runway to find that the runway surface is mostly exposed aggregate that is very slick. 'Water seemed to be coming out of the concrete.' the flaps were causing the buffet as the aircraft was flying about 50 KTS faster than indicated. Well into the flap blow back range the flaps could not blow back as the CADC didn't require this. The aircraft manufacturer will not acknowledge that this situation can happen, possibly because there might be liability on the engine repair. The flight crew debriefed with the cvr and fdr. This same scenario was tried in the simulator which could not reproduce the results. The air carrier has published bulletins to flcs cautioning them of this situation and has directed their maintenance crews to inspect the static drains regularly and more carefully. The reporter noted that the magnitude of the anomalies was decreasing with time. He did not notice when the airspeed came to zero on rollout. Callback conversation with reporter acn 352635 revealed the following information: reporter stated the FAA, NTSB, and the air carrier brought no action against the crew. Kudos were given.

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Original NASA ASRS Text

Title: AN ACR MD11 CREW HAD MULTIPLE INST PROBS ON APCH AND LNDG AT SAEZ. WX FACTORS '100 YR RAIN' AND ICING ON APCH.

Narrative: IN SUM: THE RPTING FO WAS ON HIS IOE IN THE MD11. THE CAPT WAS A SENIOR CHK PLT. THERE WERE 2 RELIEF FOS, WITH LOTS OF EXPERIENCE, IN THE JUMPSEATS. ALL ANTI-ICE WAS TURNED ON FOR DSCNT. ALL 3 ENGS SHOWED 'SELECT FADEC ALTERNATE' AT DIFFERENT TIMES DISABLING THE AUTOTHROTTLES. 'SELECT ELEVATOR FEEL MANUAL' AND 'SELECT FLAP LIMIT' WERE FLASHING ON AND OFF. THE ICING TURNED INTO HVY RAIN. THERE WAS AIRFRAME BUFFETING AS WELL AS TURB AND ROLL CTL PROBS. 'WINDSHEAR DETECT FAIL' STARTED BLINKING ON AND OFF ALONG WITH THE OTHER WARNINGS. AUTOPLT #2 WAS PLACARDED INOP AND AUTOPLT #1 DISCONNECTED 'MAYBE 10 TIMES DURING APCH.' CREW MADE A MISSED APCH AND RETURNED TO VOR WITH IMPROVING WX. ON SECOND APCH, ILS LOOKED STABLE WITH SOME BUFFETING AND NOSE ATTITUDE LOWER THAN NORMAL. ATCT WIND FOR RWY 11 WAS 170 DEGS/16 KTS. CAPT ATTEMPTED TO FLARE AT 50 FT, THEN AGAIN AT 20 FT RADIO ALTIMETER, THEN FORCED IT ONTO THE RWY, PAST TOUCHDOWN ZONE, AND 'STOOD ON THE BRAKES.' REVERSERS WERE DELAYED ABOUT 7 SECONDS BECAUSE THERE WERE NO FADECS. THE ACFT WENT OFF THE END OF THE RWY ABOUT 100 YARDS INTO MUD. THE CAPT SWERVED TO MISS AN ANTENNA. 2L SLIDE WAS DEPLOYED BUT NOT USED. THERE WAS NO FIRE OR INJURIES. THE RPTR RECOMMENDS: 50 DEG FLAP LNDGS WHEN RWY WET OR TAILWIND (OTHER ACRS DO THIS), FIX RWY, COMPARE IRS GND SPD TO IAS WHEN A DISCREPANCY IS SUSPECTED, PUT MOST EXPERIENCED PEOPLE IN SEATS WHEN THE GOING GETS TOUGH, PROVIDE MORE ALTERNATE FUEL FOR A WIDER CHOICE OF ALTERNATES, ETC. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR FLEW INTO SAEZ IN THE MIDDLE OF AN IMMENSE STORM, THE '100 YR RAIN.' THERE HAD BEEN NO RPT FROM ANY GND SOURCE OF THE SEVERITY OF THE STORM. THIS ACR HAS HAD 3 INSTANCES SIMILAR TO THIS INST PROB, APPARENTLY THE ONLY ACR TO DO SO. APPARENTLY THE ENTIRE PROB WAS CAUSED BY 'LIME DEPOSITS' THAT HAD CLOGGED THE STATIC PORT DRAINS. THIS CAUSED THE STATIC PORTS TO BE UNRELIABLE CAUSING THE CADCS TO SHUT THEMSELVES OFF AND ON. AS THE FADECS GET INFO FROM THE CADCS, THEY TOO BECAME UNRELIABLE AND THE EICAS COMMANDED THEM TO BE SHUT OFF. WITHOUT FADECS, IT TAKES 7 SECONDS FOR MANUAL ACTUATION OF THE REVERSERS AND THERE ARE NO AUTOTHROTTLES. THE CLOGGED STATIC PORTS CAUSED THE ALTIMETERS TO READ 150 FT HIGH. FORTUNATELY, THE LAND AT THE ARPT IS FLAT AND THE RADIO ALTIMETERS WORKED PROPERLY AND THE ACFT HAD VISUAL RWY CONTACT. THE CAPT IMMEDIATELY JUMPED ON THE BRAKES AFTER LNDG. WHEN THE RPTING FO ALSO GOT ON THEM, 'THE ANTI-SKID WAS GOING NUTS!' THE #3 ENG WAS DAMAGED BY MUD WHEN THE CAPT SWERVED TO MISS AN ANTENNA. THIS WAS THE ONLY DAMAGE. THERE WAS EVIDENCE OF HYDROPLANING ON THE TIRES. THE RPTR WENT OUT TO THE RWY TO FIND THAT THE RWY SURFACE IS MOSTLY EXPOSED AGGREGATE THAT IS VERY SLICK. 'WATER SEEMED TO BE COMING OUT OF THE CONCRETE.' THE FLAPS WERE CAUSING THE BUFFET AS THE ACFT WAS FLYING ABOUT 50 KTS FASTER THAN INDICATED. WELL INTO THE FLAP BLOW BACK RANGE THE FLAPS COULD NOT BLOW BACK AS THE CADC DIDN'T REQUIRE THIS. THE ACFT MANUFACTURER WILL NOT ACKNOWLEDGE THAT THIS SIT CAN HAPPEN, POSSIBLY BECAUSE THERE MIGHT BE LIABILITY ON THE ENG REPAIR. THE FLC DEBRIEFED WITH THE CVR AND FDR. THIS SAME SCENARIO WAS TRIED IN THE SIMULATOR WHICH COULD NOT REPRODUCE THE RESULTS. THE ACR HAS PUBLISHED BULLETINS TO FLCS CAUTIONING THEM OF THIS SIT AND HAS DIRECTED THEIR MAINT CREWS TO INSPECT THE STATIC DRAINS REGULARLY AND MORE CAREFULLY. THE RPTR NOTED THAT THE MAGNITUDE OF THE ANOMALIES WAS DECREASING WITH TIME. HE DID NOT NOTICE WHEN THE AIRSPD CAME TO ZERO ON ROLLOUT. CALLBACK CONVERSATION WITH RPTR ACN 352635 REVEALED THE FOLLOWING INFO: RPTR STATED THE FAA, NTSB, AND THE ACR BROUGHT NO ACTION AGAINST THE CREW. KUDOS WERE GIVEN.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.