A Convair 340-71 cargo plane, N8277Q, experienced an in-flight fire aft of the left engine shortly after takeoff from Cyril E. King Airport (STT), Saint Thomas, U.S. Virgin Islands. The flight was cleared for takeoff from runway 28 at Saint Thomas Airport at 07:47 hours local time. At 07:48:44, the local controller advised the flightcrew, “Convair seven seven quebec observe a lot of smoke coming from your left engine are you in need of any assistance sir”, to which the captain (pilot not flying) stated, “ah no we are fine…” The captain attributed the smoke trailing from the left engine to the age of the airplane. The crew then switched frequencies to San Juan Combined En Route Approach Control (San Juan CERAP). Upon receiving a message from the local controller at Saint Thomas, CERAP reported to the flight crew that flames were now observed on the left hand engine. After being notified of the fire, the co-pilot reported they checked the engine instruments and did not have any indication of a fire. About that time the owner of the company who was airborne in another airplane told them they needed to return. The captain ordered the co-pilot to go into the cabin to visually look at the left engine and after returning to the cockpit informed the captain there was a fire. The captain advised that he executed the procedures for fire checklist and secured the left engine but the fire continued. The flight returned for landing at Saint Thomas, and at 07:50:50, the pilot of a company airplane reported, “…you definitely have a fire going.” The flight continued towards Saint Thomas and ATC communications were transferred to STT ATCT. At 07:53:21, the flight was cleared to land. The captain later reported that while returning to Saint Thomas, he noticed an issue with the left aileron which the co-pilot assisted with. The airplane was landed on runway centerline at 90 knots, but the flightcrew were unable to stop the airplane. The captain also reported that there was no steering, the brakes were not working properly. During the landing roll the airport fire rescue vehicles followed the airplane while attempting to extinguish the fire and avoiding debris that was separating from the airplane. The airplane departed the right side of the runway, crossed a taxiway and a perimeter road, then went through the airport perimeter fence and came to rest upright with the nose section over a public road outside of the airport property. After the airplane came to rest, the flightcrew exited the airplane from the overwing exits, and the fire rescue vehicles converged on the airplane and extinguished the fire. PROBABLE CAUSE: “The captain’s decision to continue the flight with the left engine backfiring, resulting in an engine fire shortly after takeoff. Contributing to the accident were the captain’s decision to continue the flight following a report of black smoke trailing the airplane and in-flight fire damage to the left wheel brake system, resulting in a loss of directional control during an emergency landing.”