Boeing Engineers Drilled Wrong Holes in F-15EX Fuselage: U.S. GAO Report

Boeing mis-drilled windscreen installation holes on four F-15EXs in lot 1B, pushing the aircraft’s delivery schedule back by a couple of weeks.

Company engineers committed the mistake because they used wrong tools. Program management told auditors that the problem was discovered before holes were drilled on other aircraft of the parity. The company has promised to fix this error, the U.S. Government Accountability Office (GAO) said in a report.

The delay in the delivery schedule was also caused by problems related to a critical component of the forward part of the fuselage that ensures flight safety. The report does not provide more detailed information about this component.

Boeing was originally expected to begin delivering the first batch of F-15EX Eagle II fighters to the U.S. Air Force in December 2022. Manufacturing errors and quality issues have pushed the fighter's delivery schedule back by at least six months.

Each lot 2 fighter is now delayed by two months due to problems with the previous batch, the GAO report said. Delivery schedules are at risk of further disruption.

The U.S. Air Force currently plans to purchase 104 F-15EXs, and the proposed budget for fiscal year 2024 requests funds to purchase 24 fighters.

On Friday, Boeing spokeswoman Deborah VanNirop confirmed that the only F-15EXs delivered to the Air Force so far are two test aircraft that were delivered in the spring of 2021 and were considered Lot 1A. More than two years later, the service is still waiting for the next batch of fighters.

Boeing’s analysis predicted it would be unable to deliver the first fighter in this batch until July, and the second in August.

GAO said that if delivery of these warplanes is delayed beyond July, it will be tough to meet planned deadlines in 2023, including the declaration of initial operational capability (IOC) in July and full-rate production in October.

Cybersecurity remains the F-15EX's primary vulnerability, in the Office's view. The aircraft’s design was derived from versions of the F-15 that were sold to foreign militaries, and weren’t designed to meet the U.S. Air Force’s own cybersecurity requirements.