SUBROUTINE DRAIN(I)
C
C      ROUTINE TO DRAIN SHIELDS
C
	INCLUDE 'TRKCOMMON.FTN'
	REAL LAUNCH
	INTEGER SCAN,WHOM,CREW,HYPER,TORPS
	INTEGER GINBUF(80)
	LOGICAL*1 THRU,XSHIP,CLOAK,CLON,FBASE
	BYTE MESSAG,INITLS
C
C
	IF (IDAMGE(I,8).GT.50) GO TO 10010
	CALL TICKS (ISEED)
	IAMT = IFIX(IDAMGE(I,8)*RAN(DFLOAT(ISEED)))+1
	SHIELD(I) = SHIELD(I)-IAMT
	IF (SHIELD(I).LT.0) SHIELD(I)=0
	GO TO 10020
10010	SHIELD(I)=0
10020	RETURN
	END