Guy Norris / Wichita

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© Mark Wagner / Aviation-Images.com

The schedule for 'Italy One' has been extended to allow modifications to refuelling pod pylon

Boeing is in discussions with the Italian air force about a cure for a buffet problem on the wing-mounted refuelling pods of the service’s first KC-767A tanker, which the company confirms will delay delivery until mid-2007.

The schedule slip, which will now see the “Italy One” flight test programme completed about a year from now, means Japan’s air force will now receive the first KC-767A. Tokyo’s initial boom-equipped tanker is nearing completion at Boeing’s Wichita modification site in Kansas and is expected to fly in October ahead of a December delivery.

Boeing says there are other factors in the decision to slide Italy’s first delivery. “The customer has asked for additional enhancements to the aircraft,” it says, declining to specify the improvements.

The extension also relieves pressure on the programme, Boeing adds, because all flight-test work, modification qualification flights and aerial refuelling certification is being conducted using a single aircraft. “It all lays on one jet,” says Boeing.

The unexpected vibration cropped up during flight tests when airflow separation around the pylon connecting the refuelling pod to the wing set up a buffet in the structure. “We’re working it hard and aggressively, and we have what we believe is a solution,” says Boeing. “We are discussing that with the Italians right now.”

Italy is now scheduled to receive two tankers in 2007 and two in 2008. Its first aircraft, which has accumulated more than 250h of flight test time over 72 sorties, is due to begin the first flight refuelling tests with its boom extended next month. The full refuelling system, incorporating the boom and centre- and wing-mounted drogues, is expected to be tested for the first time over the next two to three months, says Boeing.

The second Italian tanker is undergoing modification at Aeronavali’s site in Naples, and is expected to return to Wichita for final work in November. Its third aircraft was flown to Naples in April. Japan’s second of four KC-767As will fly shortly.

Source: Flight International