20240808012529I

THE PILOT FILED AN IFR FLIGHT PLAN FROM KLBB TO REPOSITION THE AIRCRAFT TO KJYO TO PICK UP THE ^PRIVACY DATA OMITTED^ OF THE AIRPLANE FOR A RETURN FLIGHT TO KLBB. THE FLIGHT TOOK APPROXIMATELY 4 HOURS AND 44 MINUTES. THE AIRPLANE WAS PROPERLY EQUIPPED AND ADEQUATELY FUELED FOR THE FLIGHT. THE AIRPLANE'S FUEL STATUS WAS NOT A FACTOR IN THE CREW'S DECISION-MAKING.

BY APPROXIMATELY 45 MINUTES PRIOR TO THEIR SCHEDULED ARRIVAL AT KJYO AND BASED ON THEIR ANALYSIS OF THE DEVELOPING ADVERSE WEATHER IN THE NORTHERN VIRGINIA AREA, THE CREW ELECTED TO DIVERT TO WHAT APPEARED TO BE A SATISFACTORY ALTERNATE - KOKV. THE ASOS WEATHER AT 20:55L, APPROXIMATELY 34 MINUTES PRIOR TO LANDING, WAS AS FOLLOWS:

KJYO 090055Z AUTO 06009KT 1 3/4SM +RA OVC007 25/25 A2988 RMK AO2 LTG DSNT SW.

KOKV 090055Z AUTO 02005KT 4SM SCT023 SCT041 BKN110 23/22 A2986 RMK AO2.

WHILE THE WEATHER AT KJYO WAS BY THEN LOW IFR WITH HEAVY RAIN, THE WEATHER AT KOKV WAS SOLID VFR WITH SCATTERED CLOUDS WELL ABOVE THE NORMAL 1500 FOOT TRAFFIC PATTERN. THE WEATHER AT DULLES INTERNATIONAL AIRPORT WAS SIMILAR TO THAT AT KJYO SO A DIVERSION TO KOKV WAS AN APPROPRIATE AND PRUDENT DECISION.

AS THE FLIGHT PROGRESSED TOWARD KOKV, THE WEATHER AT KJYO FURTHER DETERIORATED, BUT THE WEATHER AT KOKV ALSO TOOK A TURN FOR THE WORSE, ALTHOUGH REMAINING BETTER THAN AT KJYO. AT 21:15L, 14 MINUTES PRIOR TO LANDING, KJYO WAS STILL IN HEAVY RAIN WHILE KOKV’S CEILING HAD LOWERED SUBSTANTIALLY WITH TS IN THE VICINITY. WITHIN 20 MINUTES THE VISIBILITY HAD DECREASED FROM 3SM TO 2SM AND THE TS WAS NO LONGER BEING REPORTED AT KOKV:

KJYO 090115Z AUTO 10009G14KT 3SM +RA SCT005 BKN010 OVC016 25/25 A2988 RMK AO2.

KOKV 090115Z AUTO 09007KT 030V120 3SM TS BKN009 BKN039 OVC110 23/22 A2985 RMK AO2.

AND THEN AGAIN AT 21:35L, 6 MINUTES AFTER LANDING:

KJYO 090135Z AUTO 11011G18KT 4SM RA BKN008 BKN017 OVC050 25/25 A2987 RMK AO2.

KOKV 090135Z AUTO 04006KT 2SM BKN006 BKN011 OVC024 22/22 A2985 RMK AO2.

THE CREW FLEW THE KOKV RNAV (GPS) RWY 14 LPV APPROACH BASED ON A GARMIN 530 NAVIGATION SYSTEM AND BROKE OUT AT APPROXIMATELY 1000 FEET AGL. RWY 14 IS EQUIPPED WITH HIRL, REIL AND PAPI-L BUT NOT WITH AN APPROACH LIGHT SYSTEM. THE PRIMARY RUNWAY AT KOKV IS RWY 32 WHICH IS EQUIPPED WITH MALSR. THIS IS SIGNIFICANT BECAUSE THE MALSR ASSISTS IN LINING UP WITH THE RUNWAY CENTER LINE, ALTHOUGH THE PILOT INDICATES THAT HE HAD THE HIRL IN SIGHT ON BOTH SIDES AND WAS LINED UP WITH "THE DARK SPOT IN THE MIDDLE OF THE RUNWAY LIGHTS" ON HIS LANDING APPROACH TO RWY 14. RWY 32 WAS NOT AVAILABLE DUE TO SIGNIFICANT WEATHER IN THE VECTORING AREA FOR THE RWY 32 APPROACH.

AS THE PILOT FLYING BEGAN THE LANDING FLARE, HE WAS HIT WITH WHAT HE TERMED “A SHEET OF WATER” THAT MADE IT DIFFICULT IF NOT IMPOSSIBLE TO SEE, AND BY THE TIME HE TOUCHED DOWN THE AIRPLANE WAS OFF THE PAVED RUNWAY SURFACE ON THE LEFT SIDE. HE DID NOT FEEL ANY SIGNIFICANT DRIFT, THE LANDING GEAR TRACKS IN THE GRASS PROVIDE NO EVIDENCE OF A SIGNIFICANT SIDE LOAD AND THERE WAS NO SIDE LOAD EVIDENCE OR DAMAGE TO THE AIRPLANE. IT IS POSSIBLE THAT THE AIRPLANE WAS INADVERTENTLY LINED UP SLIGHTLY LEFT OF CENTER LINE WITH SLIGHT DRIFT TO THE LEFT. THE PILOT ALSO NOTES THAT HE FELT LIKE HE HIT A WIND SHEAR DURING THE LANDING PHASE AND THAT THERE MAY HAVE BEEN A “GUST FRONT”.

UNFORTUNATELY, THE ASOS WEATHER IS NOT DEFINITIVE FOR THE 20-MINUTE PERIOD BETWEEN 21:15L AND 21:35L AND IT PROVIDES NO EVIDENCE OF OTHER THAN LIGHT, VARIABLE WIND GENERALLY FROM THE NORTH AND EAST, SO WE ARE LEFT TO SPECULATE ABOUT THE POSSIBLE CAUSES OF THE RUNWAY EXCURSION. IT IS NOTEWORTHY THAT THE RAMP AGENT THAT MET THE AIRPLANE AT THE RAMP INDICATED THAT THERE IT “WAS A VERY POOR NIGHT, WITH POURING RAIN AND CLOUDY”.

IT APPEARS THAT THE ROOT CAUSE WAS UNANTICIPATED WEATHER (HEAVY RAIN) WHICH MAY HAVE INDUCED AT LEAST MOMENTARY LOSS OF SPATIAL ORIENTATION AND DRIFT, CAUSING THE RUNWAY EXCURSION. THERE MAY ALSO HAVE BEEN SOME LATERAL COMPONENT TO THE DOWNPOUR DURING THIS TIME.