An Ilyushin Il-76 cargo plane was chartered by the Canadian Department of National Defence. It was on an ILS approach to runway 24 at CFB Trenton (YTR). The weather at the time was reported as one half mile in fog, vertical visibility 500 feet, RVR 600 feet, temperature and dew point 12 degrees Celsius and the wind was 210 at 06 knots. The aircraft struck the airport perimeter fence with the main landing gear and briefly touched down on the left main landing gear approximately 430 feet from the threshold of runway 24. The flight crew aborted the landing and applied engine power. The aircraft climbed to 3000 feet asl and entered a hold at this altitude. After approximately one hour it diverted to the Ottawa/MacDonald-Cartier airport. Ottawa tower was contacted by Trenton and advised of the incoming aircraft and that it had struck the fence on approach. Ottawa tower called out ARFF as a precaution. The Il-76 flight crew did not declare an emergency. The aircraft landed uneventfully and taxied to the local FBO. ARFF followed the aircraft and assisted the crew in removing the barbed wire that was wrapped around the left main landing gear. After a period of time the aircraft took off from Ottawa and arrived in Trenton where the onboard cargo was offloaded. Examination of the aircraft revealed substantial damage to the underside of the fuselage as a result of the impact with the fence.