Narrative:

On approach to eze ILS runway 11, the aircraft's pitot static system failed. This caused both CADC's to fail and caused numerous erroneous warnings and indications including the loss of both captain's, first officer's and standby airspeed indications. We declared a missed approach and notified ATC. The missed approach altitude was 3000 ft. We initially overflew the altitude by 200 ft and while trying to control the aircraft with no reliable airspeed indications, finally leveled at 4000 ft. Eze ATC questioned if we were level at 4000 ft and we responded to the affirmative and declared an emergency. We also requested to clear the area of all aircraft. Eze ATC never actually acknowledged our emergency in the fashion that USA controllers do. Supplemental information from acn 386739: ATC never asked our situation nor offered any assistance. We took another ILS approach to runway 11. We queried ATC several times that local traffic had been cleared from the area. All ATC would ever acknowledge is that we were #1 for the approach. With no (total loss) air data instruments and FMC malfunctions, we eventually flew the ILS runway 11 approach, landing very fast (no indicator) on a wet runway with no braking action ever reported. Maximum reverse was used to stop aircraft, with less than 500 ft of runway remaining. Doing 180 degrees on runway, saw a B747 on short final. No emergency was ever acknowledged nor any assistance offered and the local traffic was not cleared. Ends up we had a loss of both CADC's and all 3 pitot static system, GPWS, FMC, TCASII and radar. Had we not had an extra pilot onboard to assist with the multiple abnormal/emergency sits, after being up all night, or been at another south american city (with mountainous terrain), or had had a lower ceiling, the outcome would have been disastrous. Callback conversation with reporter of acn 386808 revealed the following information: the reporter is a low time captain in the MD11. He said that initially the flight crew interpreted the problem to be a central air data computer (CADC) failure. However, the reactions to the procedures they attempted to use and the information displayed soon led them to suspect that there was another cause for the problem. After landing, the maintenance technicians discovered that the 3 pitot static system had water in them and their drain system were not functioning. Additionally, the interior of the static and pressure ports were corroded. Also a 'Q' ring was mispositioned and leaking according to a maintenance technician at the company's primary MD11 facility, the captain alleged. The captain also mentioned that he thought that this was the third incident of pitot static contamination on the MD11 that his company had experienced. The reporter then told of some of his instrument indications during the event. His airspeed indications read approximately 100 KIAS below the first officer's indications and approximately 100 KIAS above the standby instrument indications. He said that none of the altimeter readouts were consistently reliable nor were any of the air data based warning system. Also, throughout the remainder of the flight, the various stall warning, overspd, GPWS, TCASII and other warning sounds would activate. He said that he used the radar ground map and an alternate FMC display for some navigation and the manually tuned VOR and ILS receivers for the approach. The pitch limit indicator would normally be available during a CADC failure, but in a pitot static failure it is not available. Neither was the protective system that causes the flaps to blow up as the airspeed approachs flap limit speeds. (A technique he attempted to use to determine his speed on final approach. This normally activates at 170 KIAS.) also the full authority/authorized digital engine control system (fadec) failed along with the autoplt. He said that he disconnected the autoplt when it attempted to react to erroneous and rapid airspeed indications by pitching rapidly up and down. At the same time, he disconnected the autothrottles. Later, as he leveled from his go around, the autothrottles re-engaged on their own and went to full power, causing the aircraft to climb from 3000 ft to 4000 ft before the captain could retard the throttles and again level the aircraft. Apparently, the captain said, the autothrottle system read one of the low speed indications and activated a protective system that attempted to react to the incorrect indication. He said that he was able to completely disconnect the autothrottles for the remainder of the flight. During the go around initiation, his airspeed read 180 KIAS, the first officer read 280 KIAS and the standby indicator had 80-85 KIAS. During the ILS approach on his landing, the captain said that he showed 160 KIAS, the first officer's 260 KIAS and the standby indicator showed 60 KIAS. The runway was wet. On short final the reporter said that he felt that the aircraft was faster than normal, so he retarded the throttles a bit sooner than normal and in spite of the loss of fadec he went to full travel on the engine reversers after touchdown. He said that he estimated the runway remaining at 300-500 ft. During his taxi-in, one of the brake temperatures went to 600 degrees C. The captain said that although the flight crew did declare an emergency several times, the controllers did not seem to understand or, at least, react as though this were an emergency. The traffic was still operating normally and the B747 that followed them was allegedly almost at touchdown as they cleared the runway. Apparently, there was no crash fire rescue equipment equipment available. The ramp and operations personnel acted as though they did not understand him when he attempted to warn them about the hot brakes and the possibility of danger from a brake fire or explosion. The captain said that he has spoken to his chief pilot and numerous maintenance personnel many times since the event with several of these people sharing data from the digital flight data recorder, however, some of the data is erroneous since, apparently, the affected pitot static system supply information to the data recorder.

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Original NASA ASRS Text

Title: AN ACR MD11 FLC HAS ALL OF THEIR PITOT STATIC SYS ADVERSELY AFFECTED BY A WATER CONTAMINATION PROB WITH AN ACCOMPANYING ARRAY OF INDICATOR, DISPLAY AND WARNING SYS FAILURES.

Narrative: ON APCH TO EZE ILS RWY 11, THE ACFT'S PITOT STATIC SYS FAILED. THIS CAUSED BOTH CADC'S TO FAIL AND CAUSED NUMEROUS ERRONEOUS WARNINGS AND INDICATIONS INCLUDING THE LOSS OF BOTH CAPT'S, FO'S AND STANDBY AIRSPD INDICATIONS. WE DECLARED A MISSED APCH AND NOTIFIED ATC. THE MISSED APCH ALT WAS 3000 FT. WE INITIALLY OVERFLEW THE ALT BY 200 FT AND WHILE TRYING TO CTL THE ACFT WITH NO RELIABLE AIRSPD INDICATIONS, FINALLY LEVELED AT 4000 FT. EZE ATC QUESTIONED IF WE WERE LEVEL AT 4000 FT AND WE RESPONDED TO THE AFFIRMATIVE AND DECLARED AN EMER. WE ALSO REQUESTED TO CLR THE AREA OF ALL ACFT. EZE ATC NEVER ACTUALLY ACKNOWLEDGED OUR EMER IN THE FASHION THAT USA CTLRS DO. SUPPLEMENTAL INFO FROM ACN 386739: ATC NEVER ASKED OUR SIT NOR OFFERED ANY ASSISTANCE. WE TOOK ANOTHER ILS APCH TO RWY 11. WE QUERIED ATC SEVERAL TIMES THAT LCL TFC HAD BEEN CLRED FROM THE AREA. ALL ATC WOULD EVER ACKNOWLEDGE IS THAT WE WERE #1 FOR THE APCH. WITH NO (TOTAL LOSS) AIR DATA INSTS AND FMC MALFUNCTIONS, WE EVENTUALLY FLEW THE ILS RWY 11 APCH, LNDG VERY FAST (NO INDICATOR) ON A WET RWY WITH NO BRAKING ACTION EVER RPTED. MAX REVERSE WAS USED TO STOP ACFT, WITH LESS THAN 500 FT OF RWY REMAINING. DOING 180 DEGS ON RWY, SAW A B747 ON SHORT FINAL. NO EMER WAS EVER ACKNOWLEDGED NOR ANY ASSISTANCE OFFERED AND THE LCL TFC WAS NOT CLRED. ENDS UP WE HAD A LOSS OF BOTH CADC'S AND ALL 3 PITOT STATIC SYS, GPWS, FMC, TCASII AND RADAR. HAD WE NOT HAD AN EXTRA PLT ONBOARD TO ASSIST WITH THE MULTIPLE ABNORMAL/EMER SITS, AFTER BEING UP ALL NIGHT, OR BEEN AT ANOTHER SOUTH AMERICAN CITY (WITH MOUNTAINOUS TERRAIN), OR HAD HAD A LOWER CEILING, THE OUTCOME WOULD HAVE BEEN DISASTROUS. CALLBACK CONVERSATION WITH RPTR OF ACN 386808 REVEALED THE FOLLOWING INFO: THE RPTR IS A LOW TIME CAPT IN THE MD11. HE SAID THAT INITIALLY THE FLT CREW INTERPRETED THE PROB TO BE A CENTRAL AIR DATA COMPUTER (CADC) FAILURE. HOWEVER, THE REACTIONS TO THE PROCS THEY ATTEMPTED TO USE AND THE INFO DISPLAYED SOON LED THEM TO SUSPECT THAT THERE WAS ANOTHER CAUSE FOR THE PROB. AFTER LNDG, THE MAINT TECHNICIANS DISCOVERED THAT THE 3 PITOT STATIC SYS HAD WATER IN THEM AND THEIR DRAIN SYS WERE NOT FUNCTIONING. ADDITIONALLY, THE INTERIOR OF THE STATIC AND PRESSURE PORTS WERE CORRODED. ALSO A 'Q' RING WAS MISPOSITIONED AND LEAKING ACCORDING TO A MAINT TECHNICIAN AT THE COMPANY'S PRIMARY MD11 FACILITY, THE CAPT ALLEGED. THE CAPT ALSO MENTIONED THAT HE THOUGHT THAT THIS WAS THE THIRD INCIDENT OF PITOT STATIC CONTAMINATION ON THE MD11 THAT HIS COMPANY HAD EXPERIENCED. THE RPTR THEN TOLD OF SOME OF HIS INST INDICATIONS DURING THE EVENT. HIS AIRSPD INDICATIONS READ APPROX 100 KIAS BELOW THE FO'S INDICATIONS AND APPROX 100 KIAS ABOVE THE STANDBY INST INDICATIONS. HE SAID THAT NONE OF THE ALTIMETER READOUTS WERE CONSISTENTLY RELIABLE NOR WERE ANY OF THE AIR DATA BASED WARNING SYS. ALSO, THROUGHOUT THE REMAINDER OF THE FLT, THE VARIOUS STALL WARNING, OVERSPD, GPWS, TCASII AND OTHER WARNING SOUNDS WOULD ACTIVATE. HE SAID THAT HE USED THE RADAR GND MAP AND AN ALTERNATE FMC DISPLAY FOR SOME NAV AND THE MANUALLY TUNED VOR AND ILS RECEIVERS FOR THE APCH. THE PITCH LIMIT INDICATOR WOULD NORMALLY BE AVAILABLE DURING A CADC FAILURE, BUT IN A PITOT STATIC FAILURE IT IS NOT AVAILABLE. NEITHER WAS THE PROTECTIVE SYS THAT CAUSES THE FLAPS TO BLOW UP AS THE AIRSPD APCHS FLAP LIMIT SPDS. (A TECHNIQUE HE ATTEMPTED TO USE TO DETERMINE HIS SPD ON FINAL APCH. THIS NORMALLY ACTIVATES AT 170 KIAS.) ALSO THE FULL AUTH DIGITAL ENG CTL SYS (FADEC) FAILED ALONG WITH THE AUTOPLT. HE SAID THAT HE DISCONNECTED THE AUTOPLT WHEN IT ATTEMPTED TO REACT TO ERRONEOUS AND RAPID AIRSPD INDICATIONS BY PITCHING RAPIDLY UP AND DOWN. AT THE SAME TIME, HE DISCONNECTED THE AUTOTHROTTLES. LATER, AS HE LEVELED FROM HIS GAR, THE AUTOTHROTTLES RE-ENGAGED ON THEIR OWN AND WENT TO FULL PWR, CAUSING THE ACFT TO CLB FROM 3000 FT TO 4000 FT BEFORE THE CAPT COULD RETARD THE THROTTLES AND AGAIN LEVEL THE ACFT. APPARENTLY, THE CAPT SAID, THE AUTOTHROTTLE SYS READ ONE OF THE LOW SPD INDICATIONS AND ACTIVATED A PROTECTIVE SYS THAT ATTEMPTED TO REACT TO THE INCORRECT INDICATION. HE SAID THAT HE WAS ABLE TO COMPLETELY DISCONNECT THE AUTOTHROTTLES FOR THE REMAINDER OF THE FLT. DURING THE GAR INITIATION, HIS AIRSPD READ 180 KIAS, THE FO READ 280 KIAS AND THE STANDBY INDICATOR HAD 80-85 KIAS. DURING THE ILS APCH ON HIS LNDG, THE CAPT SAID THAT HE SHOWED 160 KIAS, THE FO'S 260 KIAS AND THE STANDBY INDICATOR SHOWED 60 KIAS. THE RWY WAS WET. ON SHORT FINAL THE RPTR SAID THAT HE FELT THAT THE ACFT WAS FASTER THAN NORMAL, SO HE RETARDED THE THROTTLES A BIT SOONER THAN NORMAL AND IN SPITE OF THE LOSS OF FADEC HE WENT TO FULL TRAVEL ON THE ENG REVERSERS AFTER TOUCHDOWN. HE SAID THAT HE ESTIMATED THE RWY REMAINING AT 300-500 FT. DURING HIS TAXI-IN, ONE OF THE BRAKE TEMPS WENT TO 600 DEGS C. THE CAPT SAID THAT ALTHOUGH THE FLC DID DECLARE AN EMER SEVERAL TIMES, THE CTLRS DID NOT SEEM TO UNDERSTAND OR, AT LEAST, REACT AS THOUGH THIS WERE AN EMER. THE TFC WAS STILL OPERATING NORMALLY AND THE B747 THAT FOLLOWED THEM WAS ALLEGEDLY ALMOST AT TOUCHDOWN AS THEY CLRED THE RWY. APPARENTLY, THERE WAS NO CFR EQUIP AVAILABLE. THE RAMP AND OPS PERSONNEL ACTED AS THOUGH THEY DID NOT UNDERSTAND HIM WHEN HE ATTEMPTED TO WARN THEM ABOUT THE HOT BRAKES AND THE POSSIBILITY OF DANGER FROM A BRAKE FIRE OR EXPLOSION. THE CAPT SAID THAT HE HAS SPOKEN TO HIS CHIEF PLT AND NUMEROUS MAINT PERSONNEL MANY TIMES SINCE THE EVENT WITH SEVERAL OF THESE PEOPLE SHARING DATA FROM THE DIGITAL FLT DATA RECORDER, HOWEVER, SOME OF THE DATA IS ERRONEOUS SINCE, APPARENTLY, THE AFFECTED PITOT STATIC SYS SUPPLY INFO TO THE DATA RECORDER.

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.