Mr Ashak Nathwani AM designed a new air-conditioning system for HMAS Onslow which will enable the Museum to keep the vessel open to the public on hot summer days and also provide a higher standard of air quality. A donation by the Nathwani family, made in honour of the late Mrs Samim Nathwani, covered the costs of this important work.
The Museum is home to one of Australia’s Cold War remnants, the Oberon class submarine HMAS Onslow. It was given to the museum in 1999 and is a major drawcard for museum visitors. Issues arise in the heat and humidity of a Sydney summer, however, when the museum has been forced to close the vessel to the public as conditions inside become uncomfortable.
Onslow’s existing ventilation system comprised only an axial fan, which delivered unfiltered and unconditioned air through the conning tower into the occupied areas of the submarine. This led to temperatures inside the vessel reaching 4–5°C higher than outside.
Enter Ashak Nathwani AM, Researcher and Senior Lecturer in HVAC (heating, ventilation and air conditioning) at the University of Sydney. Ashak knew the museum well, having been a designer of its original air-conditioning system in 1991 as a director of leading HVAC consultants Norman, Disney and Young. Ashak was at the museum discussing all things COVID-19 and air conditioning with museum management when he heard about the continual environmental problems with Onslow. Learning that the early closures affected children during school visits and school holidays, he was inspired to design and cover the costs of a new system on behalf of the Nathwani family, in honour of his late wife, Samim.
Samim Nathwani was an early childhood development expert with two Masters degrees, who tragically succumbed to the insidious motor neurone disease (MND) in November 2019. Samim always advocated that children learn through experience and would not have been happy knowing that children were missing out,’ said Ashak. ‘It struck me that I could provide a solution through my expertise in air conditioning and the family could provide the funds to make it happen. It seemed like a fitting tribute to her passion.’
Designing and installing the system posed numerous challenges. It had to be custom-made due to size constraints, with options limited due to heritage considerations. In addition, the condensing unit had to be brought in on a barge and craned into the chamber below the main cabins. Getting the fan coil unit into the sub required many trips up and down service ladders and through a tight passageway. The fan coil unit was then connected with a large flexible duct, which was woven through the support structure within the conning tower, across to the air intake shaft for final connection. Supply air needed to be filtered with MERV-13 air filters (to meet COVID requirements). Conditioned air now flows down the air intake shaft, feeds fore and aft right through the submarine, then is exhausted at each end of the vessel. The new system has resulted in temperatures of 4–5°C lower than the ambient temperature, allowing Onslow to open fully with happy visitors, volunteers and staff.
We thank Ashak, Amyn and Rehana Nathwani for their generosity and this wonderful tribute to their wife and mother, Samim.’
