In 2004, Zelan Construction Sdn Bhd was awarded with a airport terminal building project by the government via ministry of transportation worth RM233 million. The Main contractor for this project was Pembinaan Sulaiman – Zelleco JV.
This terminal project was a critical project as the current runway and airport location has caused numerous complications and accidents during flight landing and takes off.
Tawau Airport became the second largest airport in Sabah after Kota Kinabalu International Airport.
Zelan was entrusted to bring this airport to an improved platform with this contract. was given the task to design and construct the main building terminal, control towers, runways, taxiway, Airfield Ground Lighting, NAVAIDS - Instrument Landing System (ILS) on Runway 24 comprising glide slope / DME (Distance Measuring Equipment) and Localizer and COMAIDS - INTEGRATED COMMUNICATION CONTROL SYSTEM (ICCS), featuring Air Traffic Control System (ATC), Aeronautical Fixed Telecommunication Networks / witching system (AFFN and Approach Control Facility (ACF). Other area of works includes earthworks, Sewerage reticulation network and Oxidation Pond, Water supply reticulation network, including fire-fighting supply network, Drainage system, Conduits/Ducts/Manhole for utilities and Car park. The additional expansion was also done to aaccommodate medium wide-body aircraft with 2 aero bridges.