C172 PLT COLLIDED WITH HELI DEPARTING RHV.

Narrative

AT REID HILLVIEW ARPT; I RECEIVED CLRNC TO CROSS RWY 31R AND TKOF ON RWY 31L IMMEDIATELY. CLB WAS UNEVENTFUL UNTIL 600 FT MSL WHEN A HELI (ROBINSON R22) CAME INTO VIEW FROM ABOVE AND IN FRONT OF MY ACFT. THE NOSE OF MY AIRPLANE WAS UNDERNEATH THE R SKID; CLBING INTO IT. I IMMEDIATELY APPLIED FORWARD PRESSURE ON THE YOKE WITH NO BANK AND PASSED UNDERNEATH THE HELI. I FELT NO IMPACT; EVEN THOUGH INSPECTION OF BOTH ACFT ON THE GND REVEALED THAT THE PROP HAD STRUCK THE SKID. BOTH ACFT LANDED UNEVENTFULLY. EITHER BEFORE OR AFTER I WAS CLRED FOR TKOF THERE WAS A XMISSION (TO THE TWR) BY THE HELI THAT HE WAS AT THE 'HAY PATCH' AND 'ON THE GO.' I SHOULD HAVE PAID MORE ATTN TO THIS; AND TRIED TO VISUALIZE WHERE THE HELI STARTED FROM AND WHERE HE WAS GOING. I DIDN'T EVEN TRY LOOKING FOR HIM INITIALLY; I SHOULD HAVE. UPON TKOF AND CLB; I SHOULD HAVE RADIOED THE TWR THAT I DIDN'T HAVE THE HELI IN SIGHT. DURING THE CLB; I WAS ANTICIPATING THE TWR TO INSTRUCT ME TO CHANGE TO SAN JOSE INTL TWR FREQ; TO START MY 'BAY TOUR.' THIS WAS A SMALL DISTR. I DRIFTED L OF RWY HEADING. I SHOULD HAVE MAINTAINED A COURSE OF 310 DEGS. I DON'T KNOW IF THE HELI DRIFTED R AS HE SHOULD HAVE BEEN FLYING PARALLEL TO RWY 31L TO THE L OF THE RWY.