Oracle SQL Query for two timestamp difference

Below query where given to Sysdate is between two TimeStamp

to_char(AF_AN_S, 'DDMMYYYY HH24:MI'),      AF_EET,     trim(FT_NAME) as AVT_NAME,     AC_REG,      FLB_PAX,      FLB_INF,     P_NAME,    
P_VNAME,      CLG_ACD_CODE,     P_LTR_CODE,     P_PERS_NR,      P_NR   
from     IBSDBA.MV_ACT_FLIGHT,IBSDBA.MV_AIRCRAFT,
IBSDBA.MV_FL_TYP,    
IBSDBA.MV_FLT_ART,
IBSDBA.MV_FLT_BLNG,IBSDBA.MV_VP_FLIGHT_ASSIGN,     
IBSDBA.MV_CREW_LOG, IBSDBA.MV_PERSONAL    
where      P_OWNER = 'TUI'    
and     CLG_P_PERS_NR = P_PERS_NR   
and     VAS_SEQ = CLG_VAS_SEQ    
and     VAS_AF_ID = AF_ID  
and AF_AB_S between TO_TIMESTAMP ('05.04.2012:03:00:00','DD.MM.YYYY:HH24:MI:SS')
and   TO_TIMESTAMP ('05.04.2012:17:00:00','DD.MM.YYYY:HH24:MI:SS')