British military equipment maker BAE Systems said Wednesday that first-half net profits sank almost a fifth on weak demand for Eurofighter Typhoon fighter jets.

Earnings after taxation slid 17 percent to £471 million ($618 million, 528 million euros) in the six months to the end of June, compared with £569 million a year earlier, BAE said in a results statement.

Sales meanwhile dropped almost seven percent to £8.8 billion "as a result of reduced Typhoon production activity", the group added.

The British company, which also makes Astute submarines, added however that its orders backlog increased to £39.7 billion, with a total of £9.7 billion of orders in the first half.

Eurofighter was developed by a European consortium that also comprises Italy's Leonardo (ex-Finmeccanica) and Franco-German civilian planemaker Airbus.

BAE Systems added Wednesday hat the group would have "good momentum in the second half and beyond" as a result of the British government's recently-unveiled combat air strategy.

Under the strategy, launched at the Farnborough Air Show last month, the UK government and the aerospace industry will jointly invest in next-generation combat air systems.

At Farnborough, Prime Minister Theresa May announced a £2.0-billion programme for a brand new fighter jet concept called Tempest.

The twin-engined Tempest aircraft will be operated manned or unmanned, and will boast cutting-edge features like laser-directed weapons and a virtual cockpit.

BAE is a member of the Team Tempest consortium alongside the UK government, Leonardo, European missile specialist MBDA and British engine maker Rolls-Royce.