Narrative:

15 mins after departing fay on an IFR flight to bwi, we encountered heavy rain. As the rain increased, the windshield started to leak alarmingly. The leak continued for the entire flight. An hour into the flight, the transponder malfunctioned and the VOR started swinging erratically, but both seemed to return to normal after a few mins. On initial contact with bwi approach, I was assigned ILS runway 15L. We acquired the GS and proceeded normally to within 2 mi of runway. At that point, the GS deflected full down, then full up. I held altitude and GS did a series of full deflections. I requested a position check from the tower and, was advised to go around. I advised tower that fuel would not allow for another 20 mins approach. On the second attempt, the ILS would not acquire at all and directional gyroscope began to fail. Tower was again advised of my fuel situation and I requested an alternate airport if they were not able to clear me in soon. Tower declared an emergency and gave me compass vectors to the airport. Landing was without incident on runway 10.

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Original NASA ASRS Text

Title: BE18 PLT LANDS BWI WITH NAV EQUIP MALFUNCTIONS AND LOW FUEL STATUS IN IMC AFTER BWI CTLR DECLARED EMER.

Narrative: 15 MINS AFTER DEPARTING FAY ON AN IFR FLT TO BWI, WE ENCOUNTERED HVY RAIN. AS THE RAIN INCREASED, THE WINDSHIELD STARTED TO LEAK ALARMINGLY. THE LEAK CONTINUED FOR THE ENTIRE FLT. AN HR INTO THE FLT, THE XPONDER MALFUNCTIONED AND THE VOR STARTED SWINGING ERRATICALLY, BUT BOTH SEEMED TO RETURN TO NORMAL AFTER A FEW MINS. ON INITIAL CONTACT WITH BWI APCH, I WAS ASSIGNED ILS RWY 15L. WE ACQUIRED THE GS AND PROCEEDED NORMALLY TO WITHIN 2 MI OF RWY. AT THAT POINT, THE GS DEFLECTED FULL DOWN, THEN FULL UP. I HELD ALT AND GS DID A SERIES OF FULL DEFLECTIONS. I REQUESTED A POS CHK FROM THE TWR AND, WAS ADVISED TO GO AROUND. I ADVISED TWR THAT FUEL WOULD NOT ALLOW FOR ANOTHER 20 MINS APCH. ON THE SECOND ATTEMPT, THE ILS WOULD NOT ACQUIRE AT ALL AND DIRECTIONAL GYROSCOPE BEGAN TO FAIL. TWR WAS AGAIN ADVISED OF MY FUEL SIT AND I REQUESTED AN ALTERNATE ARPT IF THEY WERE NOT ABLE TO CLR ME IN SOON. TWR DECLARED AN EMER AND GAVE ME COMPASS VECTORS TO THE ARPT. LNDG WAS WITHOUT INCIDENT ON RWY 10.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.