Auckland aviation business Airwork is being tipped to announce plans to list on the share market tomorrow morning.
A market source said a prospectus had already been shopped around to potential institutional investors.
According to its website Airwork specialises in helicopter engineering and support, helicopter leasing and charters and fixed wing operations, charter and engineering.
The company began operating out of Wellington in 1936 and now runs a head office out of Mechanics Bay in Auckland.
Airwork was previously listed in the 1970s at which time Brierley Investments built up a substantial shareholding.
But by 1984 the company wasn't performing and current chairman Hugh Jones formed a 50/50 venture with the late Timaru businessman Allan Hubbard to buy the company.
Four years later Jones bought Hubbard out, taking 100 per cent of the company.
A plan to merge Airwork with an Australian air services company and float it it on the Australian stock exchange in 2010 did not go ahead.
In September the company expanded into Europe buying 14 rescue helicopters used by a German motoring organisation.
Airwork owns a fleet of 35 helicopters in addition to the 14 bought from ADAC.
Helicopter maintenance, leasing and operations makes up about half of Airwork's business.
It also maintains and operates a fleet of 17 fixed-wing aircraft, including nine Boeing 737s, Fairchild Metroliners, Fokker F27-500 and a Piper Chieftain which are primarily used to provide freight capacity for organisations in Australasia, including NZ Post and Toll Holdings as well as charter operations.
Across the company, Airwork employs about 400 people.
Airwork chief executive Chris Hart is the son of former All Blacks coach John Hart.