EVERETT, Wash. — In the wake of Boeing’s KC-46A Pegasus topping $7 billion in losses, company officials have been eager to stem the tide of the tanker’s long-running woes — and resolve several critical issues that pose risks to its operations. The Pegasus currently has six category 1 deficiencies, Air Force terminology for problems that could cause loss of an aircraft, injury, or death. Spending money to fix those issues has helped drive Boeing’s staggering losses on the program, and is a key reason why company officials have sworn off fixed-price development contracts like those that govern the KC-46A. Work...