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1. THE FIRST OFFICER HAD A LONG DUTY DAY, AND WAS ASKED BY CREW SCHEDULING IF HE WOULD BE WILLING TO EXTEND HIS DUTY DAY PAST 12 HOURS.

2. APPROACH CONTROL CLEARED ^PRIVACY DATA OMITTED^ FOR THE MT. VERNON VISUAL APPROACH TO RUNWAY 01, AND TOLD ^PRIVACY DATA OMITTED^ TO MAINTAIN 170 KNOTS TO A 5 MILE FINAL. A SHORT TIME LATER, APPROACH CONTROL TOLD ^PRIVACY DATA OMITTED^ TO REDUCE SPEED TO 150 KNOTS AND CONTACT NATIONAL TOWER. (OF NOTE: APPROACH CONTROL DID NOT SPECIFY HOW LONG TO MAINTAIN 150 KNOTS. ALL APPROACH CONTROL SAID ON THE RADIO WAS, ?REDUCE SPEED TO 150 KNOTS, AND CONTACT NATIONAL TOWER.?)

3. ^PRIVACY DATA OMITTED^ CONTACTED NATIONAL TOWER AND TOWER CLEARED ^PRIVACY DATA OMITTED^ TO LAND ON RUNWAY 01. (OF NOTE: NO WIND READOUT WAS GIVEN WITH CLEARANCE TO LAND)

4. THE PILOT FLYING (CAPTAIN) NEVER SELECTED MANAGED SPEED, AND THE PILOT MONITORING DID NOT CATCH THE MISTAKE, WHICH WOULD HAVE SLOWED THE AIRCRAFT TO ITS FINAL APPROACH SPEED OF APPROXIMATELY 137 KNOTS. THE AIRCRAFT STAYED IN SELECTED SPEED OF 150 KNOTS, AS REQUESTED BY APPROACH CONTROL, AND CROSSED THE RUNWAY THRESHOLD AT APPROXIMATELY 150 KNOTS INDICATED AIRSPEED. (STABILIZED APPROACH CRITERIA STATES THAT TO BE STABILIZED, AN AIRCRAFT NEEDS TO BE BETWEEN -5 KNOTS TO +15 KNOTS OF FINAL APPROACH SPEED. AT 150 KNOTS ^PRIVACY DATA OMITTED^ WAS APPROXIMATELY +13 KNOTS ABOVE ITS FINAL APPROACH SPEED, WHICH WAS JUST BARELY WITHIN THE STABILIZED APPROACH CRITERIA.)

5. THE ?AUTOMATIC TERMINAL INFORMATION SERVICE? (ATIS) WAS REPORTING A TAILWIND FOR RUNWAY 01 OF APPROXIMATELY 6 KNOTS. DATA FROM SEVERAL SOURCES IN THE AIRCRAFT INDICATE THE TAILWIND CROSSING THE RUNWAY THRESHOLD WAS ACTUALLY SOMEWHERE BETWEEN 9 TO 11 KNOTS. (THE MAXIMUM AUTHORIZED TAILWIND FOR LANDING IS 10 KNOTS FOR THE A-320)

6. THE CAPTAIN WHO WAS THE PILOT FLYING ACKNOWLEDGED THAT THE AIRCRAFT DID FLOAT ?A LONG DISTANCE?. THE PILOT FLYING DID NOT ELECT TO GO-AROUND, AND LANDED LONG. IMMEDIATELY AFTER LANDING THE PILOT FLYING WENT INTO FULL REVERSE ON BOTH ENGINES AND APPLIED MAXIMUM BRAKING. AS THE AIRCRAFT SLOWED AND RUDDER INPUT BECAME LESS EFFECTIVE, THE CAPTAIN WAS UNABLE TO MAINTAIN DIRECTIONAL CONTROL, AND THE AIRCRAFT PULLED TO THE RIGHT. THE AIRCRAFT CAME TO A STOP ?JUST OFF TO THE RIGHT EDGE AND AT THE END OF RUNWAY 01. THE NOSE TIRE WAS ON THE GRASS, THE RIGHT MAIN WAS ON A DRAINAGE COVER JUST OUTSIDE OF THE RUNWAY EDGE, AND THE LEFT MAIN WAS ON THE RUNWAY.?

7. DURING THE MAINTENANCE TROUBLESHOOTING THAT OCCURRED AFTER THE OVERRUN, IT WAS DISCOVERED THAT THE ANTISKID TRANSDUCERS ON #1 AND #2 AXLES WERE READING BACKWARDS. **IN LAYMAN TERMS, WITH THE ANTISKID TRANSDUCERS READING BACKWARDS, WHEN THE RIGHT MAIN GEAR LOCKED UP, THE ANTISKID SIGNAL TO RELEASE WAS SENT TO THE LEFT MAIN GEAR. WITH NO BRAKING ON THE LEFT MAIN AND A LOCKED UP RIGHT MAIN GEAR, THE CAPTAIN WAS TRYING TO CONTROL A TURNING MOMENT TO THE RIGHT. THE TURNING MOMENT WAS SO GREAT THAT WHEN HE SLOWED, EVEN WITH FULL LEFT RUDDER INPUT, HE COULD NOT MAINTAIN RUNWAY CENTERLINE.

THE SWISS CHEESE MODEL INCLUDES ?ACTIVE? AND ?LATENT? FAILURES. ACTIVE FAILURES ENCOMPASS THE UNSAFE ACTS THAT CAN BE DIRECTLY LINKED TO AN OCCURRENCE, INCIDENT, OR ACCIDENT. LATENT FAILURES INCLUDE CONTRIBUTORY FACTORS THAT MAY LIE DORMANT FOR DAYS, WEEKS, OR MONTHS UNTIL THEY CONTRIBUTE TO THE OCCURRENCE, INCIDENT, OR ACCIDENT. YOU HAVE BOTH ?ACTIVE? AND ?LATENT? FAILURES IN THIS INCIDENT.

THE ?LATENT? FAILURE WAS THE SLICE OF CHEESE WITH THE LARGEST GAPING HOLE, AND THE MOST CONCERNING. THE LATENT FAILURE WAS THE DISCOVERY THAT THE ANTISKID TRANSDUCER WIRING WERE INVERTED AND INCORRECTLY ROUTED. WHEN THE PILOT FLYING NEEDED ALL THE BRAKING HE COULD GET, WITH THE ANTISKID TRANSDUCERS ON #1 AND #2 AXLES READING BACKWARDS, HIS MAX BRAKING WAS COMPROMISED WITH AN ASYMMETRICAL TURNING MOMENT TO THE RIGHT. THE CAPTAIN WAS FACED WITH AN INSURMOUNTABLE TASK OF STOPPING THE AIRCRAFT, KEEPING THE AIRCRAFT ON THE CENTERLINE, AND STAYING ON THE PREPARED SURFACE OF THE RUNWAY.