THE PLT OF CESSNA 152, N93193, TAXIED FOR TAKEOFF WITH THE INTENTIONS OF USING RWY 24. AT ABOUT THE SAME TIME, A NAVY H-53 (SIKORSKY) HELICOPTER ENTERED A PATTERN TO LAND ON RWY 24. WITH THE HEAVY HELICOPTER APCHG TO LAND, THE CESSNA PLT ACCEPTED AN OFFER TO TAKEOFF ON RWY 29, BUT WAS TOLD TO REMAIN CLEAR OF RWY 24. THE PLT WAS CLEARED TO TAKEOFF ON RWY 29, THEN WAS GIVEN AN EXPLANATION THAT THERE WOULD HAVE BEEN A 3 MIN HOLD FOR WAKE TURBULENCE BEHIND THE HELICOPTER. THE CESSNA PLT TAXIED TO A TAKEOFF PSN ON RWY 29 BY PROCEEDING ONTO THE EDGE OF RWY 24, THEN TURNING ONTO RWY 29 AT THE INTERSECTION OF THE 2 RWYS. THE CESSNA PLT STOPPED & HELD ON RWY 29, WITH THE TAIL OF HIS ACFT NEAR THE RIGHT EDGE OF RWY 24. THE H-53 WAS CLEARED TO LAND ON RWY 24, BEHIND THE CESSNA. THE CESSNA PLT CONTD TO HOLD NEAR RWY 24. SUBSEQUENTLY, THE CESSNA WAS OVERTURNED BY DOWNWASH FROM THE HEAVY HELICOPTER.