A Britten-Norman BN-2A-26, N906GD, collided with a ditch after the pilot reported that he lost consciousness while taxiing at Ceiba-Jose Aponte de la Torre Airport (TJRV), Puerto Rico. The pilot received minor injuries and the six passengers were not injured. The airplane sustained substantial damage. The pilot reported that prior to the flight, it was extremely hot that day and he did not eat breakfast. While taxiing to the runway, he felt dizzy, lost consciousness, and subsequently the airplane veered off the taxiway and came to rest in a ditch. When the pilot woke up the engines were still running and the passengers were asking the pilot “what should they do.” The pilot shut down the engines and instructed the passengers to open the rear door and exit through the rear of the airplane. The passengers exited though the rear doors and gathered on the taxiway behind the airplane. The pilot exited the airplane, verified that there were no injuries, and called for emergency services. Initial examination of the airplane by a Federal Aviation Administration inspector revealed that the airplane sustained substantial damage to the nose gear firewall. Weather information from the date of the accident shows a temperature of 28.3øC with a heat index of 32.7øC at 09:53 local time. PROBABLE CAUSE: “The pilot’s loss of consciousness during taxi for reasons that could not be determined based on the available information.”