The US Air Force announced Friday it was reopening a contest for a contract to build light attack aircraft for Afghanistan after an embarrassing cancellation of an award to Brazil's Embraer two months ago.

The Air Force said that a draft request for proposals would be presented April 17 to the companies competing for the job, US-based Hawker Beechcraft Corp. and Brazilian manufacturer Embraer, which is aligned with the American firm Sierra Nevada Corp.

But a final decision for the contract will not be made before early 2013, the Air Force said in a statement, with the first planes due to be delivered in the second half of 2014.

The new schedule will mean "a delay of about 15 months" from original plans, before the Air Force called off the award, the statement said.

Embraer and Sierra Nevada were awarded the $355 million contract in December for the 20 AT-29 Super Tucano warplanes but the Air Force called off the deal in February after a legal challenge from rival Hawker Beechcraft Corp.

The Pentagon's handling of the aircraft contract could have repercussions In Brazil, where the government is holding a lucrative competition for new fighter jets.

A Brazilian government source, speaking on condition of anonymity, has said that the cancellation of the contract with Embraer would "be taken into account" when Brasilia decides on a tender for 36 aircraft for its air force valued between $4 billion and $7 billion.

Brazil is expected to choose between the Rafale, made by French firm Dassault; the F/A-18 Super Hornet, manufactured by US aviation giant Boeing and Swedish manufacturer Saab's Gripen jet in the first half of this year.

The AT-29 Super Tucano, a turboprop aircraft designed for low-threat environments, is used to conduct advanced flight training, aerial reconnaissance and light air support operations.

The US Air Force chief, General Norton Schwartz, said in February the cancellation of the contract for new light attack aircraft for Afghanistan was an "embarrassment" and vowed to quickly renew the contest.