Boeing is sharpening its focus to reduce risk on its hard-fought KC-46A refueler program by building several laboratories in Washington state.

The company completed a major review with the U.S. Air Force that validated the design for the KC-135 replacement; only minor modifications are needed to move forward. USAF Maj. Gen. Christopher Bogdan, program executive officer, says he is “pleased with the path the program is on.”

The design changes needed are an outgrowth of a lack of familiarity on the part of Boeing Commercial Airplanes (BCA), which builds the 767-2C baseline platform for the tanker, with how the military uses a refueler, Bogdan tells Aviation Week. Specifically, the design “could be improved a little bit” in its ability to carry out all three adjunct missions—passenger carriage, cargo hauling and aeromedical evacuation—at once while being “user-friendly,” he says.

The most significant design modification is needed to address concerns about the location of the six emergency litter stations fixed in the aircraft for transport of injured personnel. They are located at the back of the aircraft, and Bogdan says the Air Force wants them moved forward. The current location has various medical equipment—including hoses and tubes—protruding directly underneath a window that needs to be accessed by the crew to monitor the aircraft during flight.

Other examples of changes include the addition of privacy curtains in the crew rest area. And Boeing must redesign canvas smoke barriers required to separate passengers from cargo to be easily reconfigurable by a single crewmember in less than 2 hr.

In the meantime, Boeing is also ratcheting up its risk-reduction activities. Retiring risk is critical, as estimates suggest that up to $400 million of Boeing's own funds will be needed to enable the company to deliver the first 18 combat-ready aircraft in 2017. Last year, Boeing won the work over an EADS A330-based design. The estimated cost of developing and procuring 189 tankers is $51.7 billion.

As Boeing is projected to lose money in developing the aircraft, reaching the production phase is crucial to generate revenue for stockholders and, perhaps, garner international sales.

However, the program was structured at Boeing's request to include a high level of development and testing concurrency. Company officials say this strategy is sound owing to a marriage of skills from BCA in developing the 767-2C baseline with detailed mission systems work from the Defense, Space & Security unit. Bogdan says, however, that he will not approve full-rate production until the company demonstrates performance in development.

Thus, Boeing is dedicating resources to establish several systems integration laboratories (SILs) dedicated solely to the KC-46A. Bogdan says this strategy exceeded his expectation of just one dedicated to the program.

One lab is a hardware-in-the loop SIL that includes a representative flight deck and boom-operator control station, says Jerry Drelling, a Boeing spokesman. It will also include an actual KC-46A boom in a hangar that will be used to test KC-46A control software, Bogdan adds.

The KC-46A boom design marries the outer mold line of the KC-10 boom with modern, fly-by-wire controls. This lab will be checked out by the end of June, with a full testing capability ready a year later, says Drelling.

“Before we ever start building an airplane or testing an airplane, that SIL will have 100 percent functionality relative to the software of the airplane,” Bogdan declares.

Two other SILs, slated for initial checkout by October, will focus separately on the commercial 767-2C avionics software and an integrated, military-specific suite of software for the KC-46A design. Engineers will incrementally load and test software in both labs. The mission systems lab will be fully ready for testing by October 2013.

There will also be two subsystem-testing labs—one to assess the aircraft's lighting and another “wet-fuel” facility to experiment with the entire KC-46A fuel system.

The KC-46A will be able to refuel more types of receivers than its KC-135 predecessor; these include special operations aircraft that require covert lighting, Bogdan says. The lighting lab will be checked out by the end of June, with full testing slated to start a year later. The wet-fuels lab will include a replica of the KC-46A fuel system and begin testing next year using JP8.

First flight of the first KC-46A is slated for late 2014.