LGT MAKES 2 GARS WHEN ENCOUNTERING WAKE TURB AT TOUCHDOWN. CHANGES RWYS FOR THIRD APCH.

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THE EVENT CONSISTED OF 2 CONSECUTIVE APCHS AND REJECTED LNDGS FROM 100-50 FT AGL WITH SUBSEQUENT CONTACT WITH THE RWY. WX WAS VMC WITH TEMP 4 DEGS F AND DEW POINT -9 DEGS F; WIND ON THE FIRST APCH WAS 300 DEGS; 11 KTS; ON THE SECOND APCH 310 DEGS 14 KTS. SUSPECT WAKE VORTEX INTERFERENCE FROM ACFT LNDG ON CROSS RWY. ATIS GAVE THE LNDG RWY AS ILS 22L WITH RWY 22R CLOSED. VISUAL APCHS WERE BEING CONDUCTED TO RWYS 29 AND 22L. WE WERE CLRED A VISUAL APCH TO RWY 22L WITH THE CAPT HAND FLYING THE ACFT. A DC-10 WAS JUST LIFTING OFF RWY 22L AS WE APCHED THE OVERRUN AT APPROX 100 FT AGL. AN ACFT HAD JUST LANDED ON RWY 29 AND WAS ON THE ROLLOUT. OUR APCH WAS NORMAL UNTIL JUST XING THE THRESHOLD AT WHICH TIME THE CAPT ADDED A LOT OF PWR AS THE ACFT STARTED SHARP DSCNT. HE REMOVED THE ADDED PWR AND THEN ADDED IT AGAIN AS THE ACFT TOUCHED DOWN AND BOUNCED AT WHICH TIME HE EXECUTED A GAR. THE SECOND APCH WAS ALSO TO RWY 22L WITH THE AUTOPLT COUPLED TO THE ILS. THE CAPT DISCONNECTED THE AUTOPLT AND AUTOTHROTTLE AT APPROX 200 FT AGL. AT APPROX 100 FT AGL THE WINGS STARTED ROCKING R; L; R AS THE CAPT CORRECTED WITH AILERON AND ADDED PWR. THE R MAIN GEAR TOUCHED AS THE GAR WAS ACCOMPLISHED. A SUBSEQUENT NORMAL VISUAL APCH AND LNDG WAS ACCOMPLISHED ON RWY 29. I BELIEVE THE LNDG ACFT ON RWY 29 WERE LEAVING STRONG VORTICES WHICH WERE BLOWING ONTO THE SHORT FINAL AREA OF RWY 22L. I ALSO THINK THE ACFT TAKING OFF FROM RWY 22L WERE STRENGTHENING THE VORTICES WITH THEIR TKOF THRUST BLOWING INTO THE OVERRUN. THE STABLE; COLD ATMOSPHERIC CONDITIONS WOULD BE CONDUCIVE FOR STRONG VORTICES. I BELIEVE THE RWY CONFIGN IN USE; THE WX AND WIND CONDITIONS CAUSED AN UNSAFE SIT. WE WERE THE FIRST TO ATTEMPT A LNDG WITH THE CONFIGN. DIAGRAMS BELOW SHOW WHAT I BELIEVED HAPPENED; IN RETROSPECT. AT NO TIME DID THE TWR GIVE WARNINGS OF POSSIBLE WAKE TURB.