NMAC OPERROR INVOLVING CPR X HOLDING IN POS AND ACR Y ON APCH GAR.

Narrative

IT WAS A QUIET NIGHT AT LGA AS WE TAXIED OUT TO RWY 31 TO A DEADHEAD FLT TO OUR HOME BASE AT WESTCHESTER COUNTY ARPT; A SHORT DISTANCE AWAY. IT WAS OBVIOUS WHEN WE CALLED FOR CLRNC AND WERE TOLD THAT THE CLRNC WOULD BE ISSUED AS WE TAXIED OUT THAT THINGS WERE PRETTY QUIET IN THE TWR. THE SAME VOICE ISSUED THE CLRNC AS WE HEADED FOR THE ACTIVE RWY; THE SAME ONE THAT WE HAD RECENTLY LANDED ON FOR OUR PAX DROP-OFF. AFTER HOLDING SHORT FOR A SHORT PERIOD; WE WERE TOLD TO 'TAKE POS AND HOLD.' AN UNUSUAL SILENCE FOLLOWED AND WE COMMENTED THAT THIS WAS ODD FOR LGA. AFTER SEVERAL SECONDS WE WERE CONCERNED ABOUT OUR RADIOS AND WERE REASSURED WHEN WE HEARD ACR Y FLT RPT THE 'DIALS' INTXN ON THE VISUAL APCH AND THE TWR RESPONDED. AFTER SEVERAL MORE SECONDS WE WERE AGAIN CONCERNED ABOUT THE DELAY IN HOLDING IN POS KNOWING AN ACFT WAS ON THE APCH. IN RAPID SUCCESSION SEVERAL THINGS HAPPENED. I REMINDED THE TWR VIA OUR RADIO THAT WE WERE IN POS ON THE RWY. THE FO; IN THE L SEAT FLYING THE LEG; NOTICED ON THE TCASII THAT AN ACFT WAS IMMEDIATELY BEHIND US AND DSNDING RATHER CLOSELY. WE NOTICED THE SILHOUETTE OF OUR ACFT ON THE PAVEMENT IN FRONT OF US OUTLINED BY THE LNDG LIGHTS OF THE APCHING ACFT. WE HEARD THE ROAR OF ENG PWR OVERHEAD. THE APCHING ACFT HAD NOTICED OUR PRESENCE AND COMMENCED A LAST MIN GAR. THE TWR THEN INSTRUCTED THAT ACFT TO 'GAR.' ANOTHER SILENCE FOLLOWED BEFORE ANOTHER VOICE IN THE TWR INSTRUCTED US THAT WE WERE 'CLRED FOR TKOF.' WE CHKED CLR OF THE MD-88 WHICH HAD ROARED OVERHEAD AND COMMENCED OUR TKOF ROLL. AN UNEVENTFUL BUT NERVOUS FLT WAS COMPLETED TO OUR HOME BASE. WE WERE CERTAIN THAT THE CTLR HAD FORGOTTEN US AFTER HE PUT US INTO POS ON THE RWY AND THE APCHING ACFT HAD NARROWLY AVOIDED COMPLETING HIS LNDG OVER OUR ACFT AND THE ENSUING POTENTIAL DISASTER. SUPPLEMENTAL INFO FROM ACN 296301: WITH ALL ITEMS ON THE 'BEFORE TKOF' CHKLIST COMPLETED; SAVE THE LNDG AND PULSE LIGHTS; I LINED THE CL601 A BIT TO THE R OF THE RWY CTRLINE AND HELD THE BRAKES AWAITINGTKOF CLRNC. NEXT; ACR Y JET RPTED HIS POS AT DIALS INTXN (ON THE LGA EXPRESSWAY VISUAL RWY 31); AND WAS CLRED TO LAND. MAINTAINING TFC AWARENESS VIA THIS RPT; WE NOW COMMENTED ON THE FACT THAT THE JET WAS A COUPLE MINS FROM TOUCHDOWN. AS TIME PASSED AND NO TKOF CLRNC WAS ISSUED; I BEGAN TO DEVELOP AN UNCOMFORTABLE SENSE THAT SOMETHING WAS WRONG. IN SEARCH OF MORE INFO TO QUELL MY UNEASY FEELING; I SCANNED THE COCKPIT INSTS; RADIOS; AUDIO PANEL; AND FINALLY FOCUSED ON THE TCASII. WITH GREAT DISBELIEF AND SUDDEN ANXIETY; I SAW A TARGET BEHIND US ONLY 200 FT ABOVE AND DSNDING AT GREATER THAN 500 FPM. POINTING THIS OUT TO THE CAPT; I ASKED HIM TO QUESTION THE TWR ABOUT THIS TFC. AS HE KEYED HIS MIKE THE TCASII DISPLAYED THE TFC AT 100 FT AND STILL DSNDING. EXPECTING THE ACFT TO LAND BEYOND US I DECIDED NOT TO ATTEMPT TO MOVE. ALL I COULD DO WAS LOOK THROUGH THE WINDSHIELD IN FEAR OF WHAT I WOULD SEE NEXT. I WAS EVEN MORE SHAKEN WHEN I SAW THE SHADOW OF OUR ACFT BEING CAST ONTO THE RWY BY THE LNDG LIGHTS OF THE LNDG JET! THE NEXT THING I KNEW AN MD-88 PASSED VERY LOW OVERHEAD WITH GAR THRUST SHAKING OUR ACFT ON THE RWY. FINALLY; A XMISSION WAS HEARD FROM THE TWR. IT WAS THE CTLR INSTRUCTING THE MD-88 TO GAR. THE CREW RESPONDED THAT THEY WERE ALREADY DOING SO. AND AGAIN; THE FREQ RETURNED TO AN UNSETTLING SILENCE. THE CAPT AND I LOOKED AT ONE ANOTHER: FRIGHTENED AND SURPRISED. SUPPLEMENTAL INFO FROM ACN 296083: WHILE ON DSCNT INTO LGA FROM ATL WE WERE CLRED FOR THE EXPRESSWAY VISUAL APCH TO RWY 31. APCH CTL SENT US OVER TO TWR FREQ ABOUT 2 MI PRIOR TO REACHING DIALS INTXN; THE IAF FOR THE APCH. I CALLED TWR AND TOLD THEM WE WERE AT 2500 FT AND APCHING DIALS. THE TWR CTLR TOLD US WE WERE #1 AND WE WERE CLRED TO LAND. AS WE CONTINUED THE APCH; THE CAPT BEGAN A DSCNT OUT OF 2500 FT. EVERYTHING PROCEEDED NORMALLY; AS WE CONFIGURED TO LAND. THE CAPT WAS HAND FLYING AND LINED US UP ON FINAL TO RWY 31. AT ABOUT 100 FT AGL ON SHORT FINAL THE CAPT SAID 'WHAT IS THAT? I'M GOING AROUND!' AS THE CAPT EXECUTED THE GAR MANEUVER; I COULD SEE THE SILHOUETTE OF A SMALL AIRPLANE LINED UP FOR TKOF ON RWY 31. FOLLOWING THE GAR WE MADE AN UNEVENTFUL LNDG ON RWY 31. WE WERE NOT NOTIFIED OF THE ACFT HOLDING ON THE RWY; AND IF WE HAD BEEN IT WOULD HAVE PREVENTED THIS INCIDENT. THE CTLR ADMITTED THAT THE DEPARTING ACFT WAS DELAYED DUE TO DEP TFC AND THAT HE HAD FORGOTTEN ABOUT HIM.