The Boom Solution

After months of delay, Boeing appears to have found a fix for the KC-46’s boom delivery system’s generation of “higher-than-expected boom axial loads” discovered during early test trials. The tanker successfully connected with and refueled a C-17 Globemaster III Tuesday after hydraulic pressure relief valves were installed in the boom, the Air Force announced Wednesday. The KC-46 unloaded 2,200 pounds of fuel during the four-hour flight test, a Boeing spokesman told Air Force Magazine by email. The hardware fix was also successfully tested with an F-16 on July 8. Refueling trials were delayed after issues were discovered when connecting with a C-17 that created an increased load and prevented the system from passing fuel. A software fix was initially expected to ward off delays, but in May, the Air Force announced a solution had still not been found and that it expected Boeing to miss the initial August 2017 deadline to deliver 18 KC-46A tankers due to issues with the boom. Boeing now plans to deliver the 18th aircraft in January 2018. The final Milestone C flight test—transferring fuel to the A-10—is scheduled for later this month, according to the Air Force’s release. If successful, the service will seek approval from Pentagon acquisition chief Frank Kendall to award a contract for the first two production lots. So far, the program has completed more than 850 flight hours with five aircraft, the Boeing spokesman said. “While it took some time, this week’s results confirm my confidence the Boeing team will get this figured out,” USAF Chief of Staff Gen. David Goldfein said, according to the service’s announcement. “It’s reassuring to see the program take this important step toward the production decision in August.”