MULTIPLE BIRD STRIKES ON MD11 ARE ASSESSED AS NOT CAUSING ENOUGH DAMAGE TO REQUIRE A RETURN TO DEP STATION. CONSIDERABLE DAMAGE IS FOUND ON LNDG AFTER A PACIFIC XING.

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FOLLOWING A NORMAL TKOF ON RWY 36 AT RKJK (KUNSAN AIRBASE; KOREA); DURING CLBOUT IN VMC; NIGHT CONDITIONS; A VERY LOUD; SHARP; 'BANG' WAS HEARD IN THE COCKPIT AT ABOUT 3000 FT MSL. THE BANG OCCURRED IMMEDIATELY AFTER THE SLATS WERE RETRACTED; AND AS THE CAPT WAS CALLING FOR THE AFTER TKOF CHKLIST. CAPT WAS HAND FLYING THE ACFT; ALTHOUGH NIGHT VMC PREVAILED; IT WAS A DARK NIGHT; WITH NO VISIBLE HORIZON. CREW WAS IN AGREEMENT THAT THE BANG WAS EXTERNAL TO THE ACFT; SOMEWHERE UNDER THE COCKPIT AREA. DURING THIS DISCUSSION A LIGHT; BURNING SMELL WAS DISCERNED; BUT RAPIDLY DISSIPATED. ALL ACFT SYS WERE NORMAL. THE CAPT CONTINUED MANUALLY FLYING THE ACFT TO INSURE FLT CTL INTEGRITY AND THE AUTOPLT WAS SUBSEQUENTLY ENGAGED ABOUT 8000 FT MSL. WITH NO ABNORMAL ACFT SYS INDICATIONS; I SENT THE IRO TO THE CABIN TO CHK FOR ANY ABNORMAL NOISES AND TO DISCUSS THE SIT WITH THE INFLT SVC MGR (ISM) AND TO ASSURE THE FLT ATTENDANT CREW THAT EVERYTHING WAS 'OKAY.' KUNSAN ATC ASKED IF WE REQUIRED ANY ASSISTANCE; BUT WE DECLINED AS ALL SYS WERE OPERATING NORMALLY. WE WERE THEN HANDED OFF TO THE NEXT ATC SECTOR; WHICH I BELIEVE WAS 'TOKYO CTL.' THE IRO RETURNED FROM THE CABIN AND ADVISED THAT THERE WAS NOTHING ABNORMAL IN THE CABIN AND THAT THE FLT ATTENDANTS WERE INFORMED THAT EVERYTHING WAS NORMAL IN THE COCKPIT. WITH ALL 3 CREW MEMBERS BACK IN THE COCKPIT WE DISCUSSED THE POSSIBILITIES. WE HAD RULED OUT A MIDAIR COLLISION; A BLOWN NOSE-GEAR TIRE; ANY ACFT SYS AND NOW CTRED ON A BIRD STRIKE. WE AGREED THAT A LARGE CRANE; HAWK; ETC; THAT STRUCK THE FUSELAGE; SOMEWHERE NEAR THE COCKPIT OR NOSE AREA; COULD HAVE DISINTEGRATED WITH SOME OF THESE PARTS BEING INGESTED INTO AN AIR-CONDITIONING PACK INLET OR AN ENG. WE WERE CONTINUING SCRUTINY OF ALL ENG PARAMETERS; BUT NO ABNORMALITIES WERE OBSERVED; INCLUDING THE ENG VIBRATION MONITORS. WE WERE IN AGREEMENT THAT ENG DAMAGE HAD NOT OCCURRED. I MADE THE DECISION TO CONTINUE THE FLT TO DEST AS WE HAD ABSOLUTELY NO REASON TO DO OTHERWISE. RETURNING TO KUNSAN AIR BASE OR DIVERTING TO ANOTHER SUITABLE ARPT WOULD HAVE REQUIRED A FUEL DUMP OF APPROX 130000 LBS TO ACHIEVE MAX CERTIFICATED LNDG WT. THE INFLT SVC MGR THEN INFORMED US THAT A PAX WANTED TO SPEAK WITH THE CREW ABOUT SOMETHING HE SAW ON THE #3 ENG. I ASKED THE IRO TO INVESTIGATE AND HE RETURNED SEVERAL MINS LATER AND EXPLAINED THERE WAS A DENT AT THE 12 O'CLOCK POS; OF THE ENG INLET COWL RING AND A LONG; RED STREAK ON THE SIDE OF THE #1 ENG. I HAD PREVIOUSLY TOLD THE 2 FO'S THAT CONCURRENT WITH THE LOUD BANG; I HAD OBSERVED A BRIGHT FLASH FROM THE PERIPHERAL VISION OF MY L EYE. MY THEORY WAS THAT IF A LARGE BIRD HAD IMPACTED THE L LNDG LIGHT; WHICH EXTENDS 90 DEGS INTO THE AIRSTREAM WHEN EXTENDED; THIS WOULD EXPLAIN THE BRIGHT FLASH; AS THE GLASS WOULD HAVE SHATTERED AT THIS IMPACT. WE FURTHER DISCUSSED SOME OF THE CARCASS CONTINUING PAST THE #1 ENG; WHICH WOULD EXPLAIN THE RED (BLOOD) STREAK AND THE REST GOING UNDER THE FUSELAGE AND IMPACTING THE #3 ENG COWL; OR PERHAPS THERE WERE 2 OR MORE BIRDS? I THEN ESTABLISHED A PHONE PATCH WITH COMPANY MAINT CTL TO ADVISE THEM OF THE DENT IN THE #3 COWL RING; PROBABLE BIRD(S) STRIKE AND MARGINAL DISPATCH CAPABILITY OF THE ACFT AT ANCHORAGE. THE REST OF THIS FLT WAS NORMAL AND WITHOUT INCIDENT. DURING POSTFLT WE DISCOVERED THE MAGNITUDE OF THE SIT FOR THE FIRST TIME. WE HAD APPARENTLY IMPACTED A LARGE FLOCK OF BIRDS NUMBERING 30-40; WHICH HAD DESTROYED BOTH LNDG LIGHTS AND DENTED THE #3 AND #1 ENG INLET COWL RINGS. RED 'HIT' MARKS POCKED THE ACFT FROM THE PACK INLETS BACK TO THE SLATS; WHERE ONE CARCASS REMAINED; AS THE SLATS TRAPPED IT AT THE O DEG/RETRACT POS. THE #1 ENG COWL DENT WAS NOT VISIBLE INFLT AS IT WAS ON THE OUTBOARD SECTION. BASED ON THE AVAILABLE INFO INFLT AND COMPLETE LACK OF ANY ACFT SYS ABNORMALITIES; I BELIEVE WE MADE THE CORRECT DECISION TO CONTINUE TO DEST.