On February 16, 1994, about 0921 eastern standard time, a Beech G18S, N49K, registered to H and G Import Export Corp., crashed at Fort Lauderdale, Florida, while returning to land following loss of power in one engine. The flight was a 14 CFR Part 91, business flight. Visual meteorological conditions prevailed at the time and a visual flight rules flight plan was filed. The airplane was destroyed and the commercial-rated pilot received minor injuries. The flight originated at Fort Lauderdale, Florida, on February 16, 1994, at 0916. The pilot stated that while climbing after departure from Fort Lauderdale International Airport, en route to Freeport, Bahamas, the left engine backfired and began to run rough. He moved the throttle to the idle position and the engine continued to run rough. He then shut down the engine and feathered the propeller. He elected to return to his departure runway 9 left due to the wind conditions. While turning from base leg to final approach he notices the altitude at 75-100 feet. "The aircraft was buffeting and beginning to stall." He was losing altitude rapidly and realized he would not make it across the highway before the runway. He then looked for an alternative landing spot which turned out to be a vacant lot between two buildings. Witnesses observed the airplane on downwind approach to runway 9 left at 800 to 1,000 feet agl. The landing gear was extended at this time and the left engine not operating and the propeller was feathered. The airplane started a turn on to base leg and was observed to yaw into the left engine. The airplane rolled left and descended. The wings leveled at about 400 feet agl and the airplane was now heading east. The airplane continued to descend and collided with trees and the ground where it came to rest in a vacant lot about 1/4 mile from the runway. Examination of the crash site indicated the aircraft collided with power lines and trees and then touched down upright in a vacant lot. As the aircraft skidded to a stop it collided with additional trees. The aircraft's landing gear and flaps were in the retracted position. The right and left engines had separated from the aircraft during the crash sequence. Tree limbs up to 3 inches in diameter were found cut in the path of the right engine. The right propeller blades were in the low pitch position and each blade had chordwise scratches and rotational twisting damage. One blade had separated from the hub during the crash sequence. The left propeller blades were in the feathered position and bent without rotational twisting. All cargo was removed from the aircraft and was found to weigh 2,080 pounds when weighed. Examination of the left engine indicated that each cylinder had compressions below 55 pounds when tested. No evidence of cracked cylinders was noted. The crankshaft, camshaft, valve train, and all accessory drives operated normally when the engine was rotated. Each of the magnetos sustained impact damage. Testing of the magnetos revealed no evidence to indicate precrash failure or malfunction. Testing of the carburetor revealed no evidence to indicate precrash failure or malfunction. The carburetor inlet fuel screen was found to have been previously damaged during maintenance and allowed unfiltered fuel to enter the carburetor.