PA28 PLT ACCEPTS HOLD SHORT CLRNC ON LNDG; THEN IS UNABLE TO COMPLY. PLT NOTIFIES TWR LCL CTLR WHO ISSUES DA20 ON SHORT FINAL FOR ANOTHER RWY GAR INSTRUCTION.

Narrative

CERTIFIED PLT WITH APPROX 140 HRS VFR FLEW PA28 FROM PNE TO DCA JAN/XA/99; LNDG APPROX XA00. CERTIFICATED PLT FLEW THE FLT UNDER VFR CONDITIONS AND CLRNC INTO CLASS B AIRSPACE FROM PHILADELPHIA THROUGH DCA. PLT X WAS INSTRUCTED BY ATC TO CROSS RWY 18 AS SOON AS PRACTICABLE AFTER LNDG RWY 21 TO FACILITATE LNDG FALCON JET Y ON RWY 18. APPROX 2 MI OUT; ATC CALLED OUT A WAKE TURB WARNING DUE TO HVY TFC DEPARTING RWY 18. PLT SLOWED DOWN FROM 110 KTS TO 80 KTS TO AVOID LNDG WITH WAKE TURB IN AREA. IT IS PLT'S FIRM BELIEF THAT THE WAKE TURB WARNING AND SUBSEQUENT DECREASE IN SPD AFFECTED SPACING THAT ATC HAD SET UP FOR FALCON JET. PLT WAS ALREADY CLRED TO LAND AND WAS LNDG WHEN ATC ASKED IF IT WOULD BE POSSIBLE TO HOLD SHORT OF RWY 18. PLT RESPONDED TO ATC BUT DURING THE RESPONSE THE ACFT PASSED THE HOLD SHORT LINE FOR RWY 18 JUST PAST THE HOLD SHORT LINE BUT NOT IN THE INTERSECTING RWY. PLT PROMPTLY ADVISED ATC THAT ACFT WAS INDEED PAST THE HOLD SHORT LINE AND AWAITED FURTHER INSTRUCTIONS FULLY AWARE THAT FALCON WAS LNDG RWY 18 AND WAS VERY CLOSE. ATC GAVE GAR INSTRUCTIONS TO FALCON JET AND REQUESTED THIS PLT TO CROSS RWY 18 AND EXIT VIA TXWY. PLT FOLLOWED ALL ATC INSTRUCTIONS BUT FULLY UNDERSTANDS THAT ACTIONS COULD BE INITIATED DUE TO IMPROPER SPACING AND CONFUSION ON THE PART OF BOTH CTLR AND PLT. PLT'S MAIN CONCERN IS THAT IT MAY HAVE BEEN IMPROPER TO STOP PLANE AFTER HOLD SHORT LINE OF RWY 18 ON RWY 21 DUE TO THE ATC REQUEST MADE DURING TOUCHDOWN. PLT'S PRIOR INSTRUCTION HAD BEEN TO CROSS RWY 18 AS SOON AS PRACTICABLE BUT THE SECOND REQUEST WAS CONFUSING AND THE FALCON JET WAS ALMOST ON THE GND AT THAT POINT. PLT'S MAIN CONCERN WAS THE SAFETY OF ALL CONCERNED AND TRIED HIS BEST TO STOP PRIOR TO HOLD SHORT LINE OF RWY 18 BUT STOPPED A FEW FEET AFTER HOLD SHORT LINE. INSTEAD OF LNDG ON NUMBERS; PLT COULD HAVE LANDED 2000 FT INTO RWY 21 MAKING THE PRIOR INSTRUCTION FROM ATC TO CROSS RWY 18 A NO BRAINER. SUPPLEMENTAL INFO FROM ACN 426323: HANDHELD MIKE HOLDER WAS BROKEN. I PLACED MIKE ON FLOOR BTWN PLT AND PAX. MIKE MUST HAVE SHIFTED DURING FLT. PAX HAD HIS FOOT ON MIKE DURING GND OPS AND MORE THAN LIKELY KEYED MIKE FOR SEVERAL MINS ON GND FREQ. WE WERE NOTIFIED BY GND OF STUCK MIKE.