ACFT DAMAGED BY INFLT ENCOUNTER WITH HAIL IN CLBING TFC IN PROX OF TSTM ACTIVITY.

Narrative

UPON RPTING TO MSP FOR FLT; IT WAS EVIDENT THAT A TSTM SYS WAS W OF THE ARPT MOVING E. I CALLED THE DISPATCHER AND HE PULLED UP A RADAR PICTURE OF THE MSP AREA AND GAVE ME A DESCRIPTION OF THE STORM AS BEING 20 NM W OF THE MSP ARPT; 20 NM WIDE AND MOVING AT 30 KTS WITH MOSTLY LEVEL 1 AND 2 RETURNS WITH A FEW AREAS OF LEVEL 3 AND 4 MIXED IN. I ALSO CALLED UP THE RST RADAR RPT (SD) SINCE THE MSP; SD; WAS PPIOM. THE MAIN PART OF THE STORM PASSED OVER MSP AT APPROX AB40Z. WE DEPARTED THE GATE AT AC15Z AND TAXIED TO TXWY C WHERE WE STOPPED TO STUDY THE RADAR RETURNS AND DETERMINE THE BEST RTE OF FLT OUT OF MSP. THE RADAR SHOWED SEVERAL CLR AREAS WITH NO CONTOURING AND NO ATTENUATION. WE TOOK OF AT AC36Z FROM RWY 11R WITH A HDG OF 140 DEGS (THE HDG SHOWING CLR OF RADAR RETURNS AND ALSO BEING USED BY OTHER ACFT). AT ABOUT 14000 FT WE ENCOUNTERED HVY RAIN; EVEN THOUGH THE RADAR WAS SHOWING NO RETURNS. AT ABOUT FL180 WE STARTED ENCOUNTERING HAIL. AT THAT TIME WE TURNED ON FLT START IGNITION. THERE WAS VERY LITTLE TURB. THE HAIL CONTINUED TO INCREASE IN INTENSITY AND THE L1 AND R1 OUTER WINDSHIELDS CRACKED AT APPROX FL200. AT FL210 WE WERE CLR OF THE STORM. WE INFORMED MSP DEP CTL OF THE HAIL AND ADVISED THAT THEY NOT RTE ANY OTHER ACFT IN THAT DIRECTION. THE FE WENT TO THE CABIN TO CHK FOR ANY DAMAGE TO THE WINGS. NONE WAS FOUND. WE CALLED MAINT TO RPT TO THEM THE SIT AND CONDITION OF THE WINDSHIELDS. WE COMPLETED THE FLT WITHOUT FURTHER INCIDENT. APPARENTLY THE RAIN WAS CAUSING THE X-BAND MONOCHROME RADAR TO ATTENUATE DUE TO THE RAIN ON THE RADAR NOSE CONE. WHEN WE STARTED GETTING RAIN WE SHOWED NO RADAR RETURNS; ONLY A CONSTANT GREEN BAND. SUPPLEMENTAL INFORMATION FROM ACN 249761: THE POOR PERFORMANCE OF THE RADAR MADE DECISION MAKING EXTREMELY DIFFICULT. WE HAD NO REASON LOOKING AT THIS RADAR TO DOUBT ATC'S HDG. ONCE IN THE HAIL IT WAS IMPOSSIBLE TO HEAR ANY VERBAL COM IN THE COCKPIT. THERE WAS NO INFO EITHER BY RADAR OR PREVIOUS ACFT DEP WHICH WOULD HAVE WARNED US OF THIS PROB. OTHER ACFT HAD USED THIS SAME DEP MINS BEFORE WE DID; WITH NO COMPLAINT. THE DEP WAS BASED BOTH ON INADEQUATE AND INCORRECT INFO PROVIDED BY ON- BOARD RADAR AND ATC. WITH MORE CORRECT AND COMPLETE INFO THE DEP MAY HAVE BEEN ACCOMPLISHED IN A DIFFERENT DIRECTION OR DELAYED.