A Swearingen SA226-TC Metro II turboprop sustained substantial damage in a gear-up landing accident at Lanseria Airport (HLA), South Africa. The 13 passengers and two pilots were not injured. The Metro II, registered ZS-ZOC, was chartered to fly journalists to a FIFA World Cup football match in Polokwane. It took off at 08:04 from Lanseria to Polokwane. The flight crew reported that the flight was uneventful until during descent and approach to runway 05 at Polokwane. The flight crew selected the undercarriage control lever to down position. The flight crew observed the ‘undercarriage unsafe’ red warning light going on inside the cockpit. The ‘undercarriage unsafe’ red warning light indicated that the left side main landing gear was not extending. The approach was abandoned and the crew made a fly-by past the control tower. The ATC informed the flight crew that the left main landing gear doors were partially open, but the gear had not extended. The aircraft entered into a holding pattern for approximately 15 minutes, during which period the flight crew attempted to extend the landing gear. The undercarriage was recycled several times with the same indication that the left main landing gear had failed to extend. The flight crew then executed the emergency extension procedures several times, with no success. The flight crew also continued with other recommended best practice emergency procedures which included various manoeuvres to induce additional “G” forces on the aircraft to try and release the left main landing gear, but this was also unsuccessful. The flight crew elected to return to Lanseria because they thought that the facilities to handle emergencies of this nature were better. The flight crew continued to execute the emergency gear deployment procedures while en route to Lanseria, without success. When the aircraft was inbound approaching Lanseria, the flight crew establish contact with ATC and they were given instructions to hold over the beacon (HBV) near Hartebeespoortdam. After a while they were routed to hold over the beacon (LIV) near Lanseria, where the flight crew burned off fuel. All normal and emergency procedures used by the flight crew to extend the left main landing gear were unsuccessful. After being airborne for a period of 2.9 hours, the flight crew were given clearance by ATC to land on runway 06. The intention of the flight crew was to do a low level fly-past in front of the tower for confirmation that the left main landing gear was still not extended. The flight crew then recycled the gear up in preparation for the planned wheels up emergency landing. The flight crew made a teardrop manoeuvre to turn back in the opposite direction to approach runway 24R. During short finals overhead the threshold, prior to touchdown, the flight crew shut down both engines, feathered the propellers and switched off all the electrical power. The radios were off, thus no further communication between the flight crew and Lanseria ATC was possible. The aircraft came to a gradual stop on its lower fuselage on the centreline of the runway Probable Cause: The pilot executed a belly “wheels up” emergency landing after the left main landing gear failed to extend. Contributory Factors: The new tyres installed on the main landing gear wheels were not in compliance with the instructions of the Fairchild Service Letter 226-SN-131.