Just days after relaunching a multi-billion dollar competition to replace the US Air Force’s ageing fleet of air refuelling tankers and insisting it would be a model of impartial procurement, the Pentagon has come under attack for “unfair” practices.

On Friday the department of defence released its draft request for proposals (RFP), the first step in the acquisition process. It assured Congress and the media that the contest would be played “straight down the middle”.