The projection comes as a consortium led by BAE Systems, Rolls-Royce, MBDA and Leonardo that is driving the project to get the new aircraft into service by 2035.
An economic analysis of Tempest conducted by PwC calculates the program will also support 20,000 skilled jobs a year between 2026 to 2050.
More than 200 UK companies including SMEs are working on Tempest employing about 1,800 people.
BAE, which released the report, said the potential economic benefit of Tempest did not include any export sales.
Citing “commercial sensitivities”, the defence giant declined to say how much producing Tempest was expected to cost. Defence analysts suggest the bill could top £25bn.
Read more: The Telegraph