Boeing has revealed plans to slash C-17 production by one-third by 2011, with deliveries falling from 15 in 2009 to 13 in 2010 and 10 next year. The slower output will preserves C-17 assembly until October 2012, the company says.
USAF officials, meanwhile, are lobbying Congress to stop adding more C-17s to the budget and to repeal a ban on retiring C-5As.
"I understand the angst, but the reality is that we need to move forward," Gen Norton Schwartz, USAF chief of staff, told the House Armed Services Committee on 23 February.
The USAF wants to rebalance its strategic airlift fleet with 317 aircraft, including 223 C-17s and 94 C-5s, and an undetermined number of re-engined and upgraded C-5Ms. The plan calls for retiring 17 of its 59 C-5As to partly offset the 43 C-17s added by Congress above the USAF's acquisition plans.
Congress has blocked the USAF from retiring any C-5As until at least 90 days after the service submits a report assessing the C-5M initial operational test and evaluation phase. That report is due to be submitted to Congress around 15 March, Schwartz says, and is likely to endorse the previously troubled re-engining programme.
"The re-engining has been really successful," Lt Gen Mark Shackelford, USAF acquisition chief, said on 23 February at an Air Force Association event. The USAF wants "as many updated C-5s that we can push through", he added.
The operational assessment showed the re-engined C-5M is far more capable and reliable than the C-5A, says Shackelford. One C-5M even delivered cargo directly to Afghanistan, according to Lockheed.
The USAF plans to upgrade 48 C-5Bs to the M-standard over the next six years, and its remaining C-5As could also could be modernised later.
Despite the plan, the USAF will continue to face pressure from some quarters of Congress to buy more C-17s, or at least make room for them in the inventory.
Boeing plans to keep C-17 production going through at least 2013 at the reduced rate. India has signed a letter of request to buy 10 C-17s, although the timing of a contract award remains unclear. Boeing says it wants to keep the line open beyond 2013 for continued international and domestic orders.