In Singapore, Hamilton Sundstrand Pacific Aerospace Pte Ltd (HSunpac) was established in 1971. It is a wholly owned subsidiary of US- based United Technologies Corporation.

HSunpac has two manufacturing facilities in Singapore located in Bedok and Changi.

The Bedok plant manufactures advanced technology components and gears for Hamilton Sundstrand's Constant Speed Drive, Integrated Drive Generators (IDG), Engine Gearbox, Flap/Slat Actuation System and Engine Starter. The Bedok plant is designated as the "Center of Gear Excellence".

The Changi plant is designated as "Center of Complex Machining". The main products are Compressor Wheel, Turbine Wheel, Gearbox Housing for Auxiliary Power Unit and housing for main fuel and lube pump.