The US Air Force is letting its close air support workhorse die a slow death by shelving plans to replace the remaining wings on the rest of its Fairchild-Republic A-10C fleet, according to a government watchdog group.

Despite cries from Congress to keep the A-10 flying and funding for new wings outlined in the fiscal year 2018 defence policy and appropriations bills, air force leadership neither has plans to implement the re-winging programme nor fly more than the aircraft that already received upgrades, according to a 17 January from the Project on Government Oversight.

The A-10’s civilian programme manager at Air Combat Command told USAF personnel the re-winging effort will not happen, POGO reports. That will force the USAF to cut three of its nine A-10 squadrons.

In 2007, the USAF awarded Boeing a $2 billion contract to deliver 242 replacement wing kits and extend the A-10’s life by 20 years. There is a dispute among the three parties – the USAF, Boeing and POGO – over how many wing sets have been completed. The USAF says 173 wing kits for the A-10 have been ordered. Boeing says it has already delivered 173 wing kits for the A-10, but several more remain on back order. POGO, meanwhile, says only 171 wing kits have been delivered, with no more deliveries planned.

In any event, the air force has never extended the order beyond the first 173 wing kits, a Boeing spokesperson tells FlightGlobal. POGO reports the contract lapsed in 2016.

“The contract has not closed, and we’re still delivering wings,” Boeing says in a statement.

However, Boeing must now wait on funding for additional wing sets in order to finish work on the entire fleet. That’s where $103 million approved in Congress’ FY2018 National Defense Authorization Act defence policy bill comes into play, which would compete the award to establish a new wing production line and produce another set of four wings.

“Pending approval of the FY2018 appropriation, the air force plans to use the $103 million authorized in the FY2018 NDAA to award a contract, establish a new wing production line and produce four additional A-10 wings," the USAF says in a statement. "Establishing the production line will enable the air force to procure additional wings if the decision is made to do so in future budgets.”

But appropriations for the re-winging effort are up in the air, as Congress debates its spending bill this week and attempts to avoid a government shutdown. If Congress chooses to pass a short-term spending bill that would fund the government until mid-February, known as a continuing resolution, the USAF would be unable to award any new start programmes, including the re-winging effort.

In December, members of Congress issued the dire warning that more than 100 aircraft in the almost 290-strong A-10 fleet will be grounded if the USAF does not receive funding for new wings.

The USAF has tried to phase out the A-10s several times over three decades, but champions of the Warthog in Congress, like former A-10 pilot Rep. Martha McSally of Arizona, have come to its rescue. In an exit interview with FlightGlobal in 2017, outgoing Air Combat Command head Gen Herbert Carlisle appeared to take a turn from official air force policy, assuring the new Boeing-produced wings could stretch the A-10’s life out as far as the 2030s. Air force chief of staff Gen David Goldfein appeared less optimistic on the A-10’S fate, saying in early 2017 that the aircraft’s retirement would at least be delayed.