The pilot started the helicopter's engines on an intended flight prior to the accident flight. A fireman saw sparks coming from the right engine and notified the pilot. In his written statement the pilot said he shut the engines down and cancelled the flight. A medical crew member aboard the helicopter said he saw sparks coming from the engine exhaust and noticed the engine temperature 'reading well above normal.' He also said he saw the engine's chip detector light illuminate. He said the pilot 'played with the throttles a little bit to try to get the temperature under control.' The pilot shut the engines down and the non-flying crew members returned to their home base via ground transportation. The next morning the pilot attempted to ferry the aircraft with one engine. The pilot started the right engine and performed a takeoff with both engines running. After takeoff, the right engine's temperature rose and the pilot shut the engine down. The helicopter could not fly adequately with the power from the left engine and altitude could not be maintained. The helicopter collided with a tree and then the ground. Examination of the right engine revealed extensive heat damage to the gas producer turbine wheel with 20-30% deterioration of all blades.