RAF MILDENHALL, England — Airmen of the only air refueling wing in Europe got some good news last week when a huge deal was brokered to replace its aging KC-135 Stratotankers.

On Feb. 29, Northrop Grumman beat out Boeing to secure a $35 billion contract to build up to 179 new tankers, dubbed KC-45A.

The proposed tanker will have increased defensive capabilities and be able to carry more cargo and personnel than the KC-135, which came on the scene in the 1950s. Another advantage is the KC-45A’s ability to receive fuel, a capability only a handful of the current tankers possess, Lt. Gen. Donald J. Hoffman, military deputy in the office of the assistant secretary of the Air Force for acquisition, said in a recent news release.

Those who work closely with Mildenhall’s fleet of 15 KC-135 Stratotankers spoke highly of the Air Force’s decision. Each day, KC-135s attached to Mildenhall’s 100th Air Refueling Wing knock out roughly eight to 10 refueling missions, taking them to locations over Europe, Africa and Southwest Asia.

“I think it’s time,” Airman 1st Class Jeff McWhorter, a 100th Aircraft Maintenance Squadron crew chief, said of swapping out the KC-135. “The aircraft is 50 years old.”

It’s still unclear when this base will receive the new tankers. In 2010, the KC-45A is expected to begin test phases, with the first mission-capable aircraft ready by 2013, according to an Air Force report.

The Air Force has projected that some KC-135s might have to keep flying until 2040 when the entire fleet has been replenished, said Col. JD Clifton, the 100th Operations Group commander who continues to pilot the KC-135 on routine missions.

“It’s going to take a number of years to replace it completely,” he said. “I’m excited that we have started that process. ...”

Maintainers said this week that the KC-135 is reliable and consistently surpasses mission-capable rates. However, leaky fuel cells can be a recurring problem.

“We have been plagued by fuel cell leaks,” said Col. Michael Saville, the 100th Maintenance Group commander, who added that the Air Force is in the process of changing them out.

“Our maintainers do an outstanding job of keeping them mission ready.”

Keeping such an old aircraft up and running is not an easy task.

“It is pretty challenging,” said Master Sgt. Kiwon Kim, the lead production superintendent at the 100th Aircraft Maintenance Squadron.

“Granted, as they get older, they’re going to require more maintenance. That’s why we’re glad to see the new tanker as far as maintenance is concerned.”

Over the years, KC-135 tankers have gone through major overhauls and modifications to its engine, cockpit, navigational systems and software, among other things, Saville said.

But pouring money on new gadgets and parts for the KC-135 is not a long-term solution. That’s where the new KC-45A comes in.

“It’s going to give us the ability to continue to operate in those areas and do things that future missions [will] require from us,” Clifton said. “We would have to extensively modify [the KC-135] to meet those challenges.”

Until this base gets its stock of new aircraft, the trusty KC-135 will be in charge of its air refueling business.

“They may take a little longer to maintain because they’re getting older,” Kim said of the planes. “But I don’t see these aircraft falling from the sky … as long as the parts keep flowing to us.”