Shortly after the helicopter cleared the helipad, the pilot noticed that although he had the cyclic positioned in the full forward position against the stop, the airspeed was gradually decaying. The pilot then removed his seatbelt and moved forward. Along with continuous changes of power, this enabled the pilot to maintain flying speed with a nose-up attitude. In the attempt to land at the helipad, which was adequate for normal operations but not meant for emergency operations, the pilot lost control of the helicopter and executed a 180 degree pedal turn. He then attempted to land in a small clear area across a highway from the helipad but failed to clear a guard rail with the tailrotor. The pilot bottomed the collective and departed the aircraft during the second contact with the ground. The helicopter exploded and slid down an embankment. Both the pilot and the operator concur that this accident occurred due to an aft center of gravity problem.