Boeing has been awarded a $55.5 million contract by the United States Air Force for the redesign of the KC-46A boom telescope actuator. The work is expected to be completed by February 2021.

When the USAF started accepting deliveries of the KC-46, set to replace another Boeing aircraft, the KC-135 Stratotanker in service since 1957, a few technical setbacks were identified.

Aside from two suspensions of deliveries due to loose tools and foreign object debris found in the tankers, it came to light that the “Remote Vision System” (RVS), developed by Rockwell Collins, does not work as intended, especially under certain light conditions. The RVS is composed of several sensors and cameras that should help a boom operator during aerial refueling. But the USAF has discovered discrepancies between the motion shown by the RVS and what was happening in real life. Boeing has agreed to fix the RVS at its expense, a process that could take three to four years.

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The United States Air Force announced that it accepted to receive its first KC-46A Pegasus tanker from Boeing on January 10, 2019, more than a year after due date. But it might take a bit longer to see it in action.
 

Another problem resides in the design of the boom itself. During aerial refueling, both a tanker and receiving aircraft must work together to connect the nozzle of the boom to the “receptacle” of the aircraft.

In 2016, during the Milestone C of the conception phase, which allowed to proceed with the production of the multirole tanker, Boeing presented a design that met the international standards of 1,400 pounds for thrust resistance ‒ which the USAF accepted. However, multiple aircraft, including the A-10 ground attack aircraft, happened to require a lower threshold as they cannot generate sufficient thrust.

The USAF agreed to fund the modification “for the system-level hardware and software critical design review”. The redesign work, valued at $55,5 million, should take two years to complete and is expected by February 2021. However, the retrofitting of the tankers that have already been delivered may add to the price.

The KC-46A Pegasus tanker, that recently achieved certification testing for the F-35,  has been plagued with technical problems throughout its development. Issues with fuel distribution, delays in certifications and delivery of wing aerial refueling pods have led Boeing to pay already more than $3 billion in cost overruns.