A Pentagon report is warning that the U.S. Marine Corps' oldest F-35B Joint Strike Fighters could remain airworthy for just over a quarter of their expected lifespan due to 'serious structural problems'.
According to Bloomberg one early version of the jet, known as 'early block F' and bought by the Marine Corps, could fly for just 2,100 flight hours, which the report says is 'well under' the expected service life of 8,000 hours.
The plane has been hit by a huge list of issues, and is over a decade late, with final cost estimates for the US military expected to reach $1.5 trillion.
It is being tested by military forces around the globe, with the Royal Air Force already having taken delivery of its test planes, known as the Lightning.
Although the structural issues are believed to affect only a small number of planes, the Pentagon test office 2018 annual report obtained by Bloomberg also found a huge host of flaws in all versions of the fighter, ranging from cybersecurity issues to 'unacceptable' problems with the accuracy of guns fitted to the Air Force's A version of the plane.
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The F35-B. According to Bloomberg one early version of the jet, bought by the Marine Corps, could fly for just 2,100 flight hours, which the report says is 'well under' the expected service life of 8,000 hours.
The latest Pentagon report uncovered a host of problems with all three versions of the F35Serious structural problems that cuts the lifespan of the B variant Cybersecurity issues 'Unacceptable' problems with the accuracy of guns fitted to the Air Force's A version of the plane Computerized maintenance tool known as 'ALIS' doesn't 'yet perform as intended' Maintenance personnel, pilots 'must deal w pervasive problems w data integrity, completeness on a daily basis'
The finding means some jets expected to start hitting service life limit in 2026.
Bloomberg claims the report also said maintenance personnel and pilots 'must deal w pervasive problems w data integrity, completeness on a daily basis.'
Test office director Robert Behler said in the new assessment improvements 'are still not translating into improved availability'.
He also warns there is no 'improving trend in' aircraft availability to fly training or combat missions as it's remained 'flat' over the past 3 years, according to Bloomberg.
The details come a day after Defense Sec. Pat Shanahan told reporters the F-35 'has a lot of opportunity for more performance.'
Lockheed Martin, who manufactures the F-35 Joint Strike Fighters, hit back at the report, claiming 'The F-35s operating today are delivering exceptional capability, lethality and connectivity around the globe.
'Items identified in the Annual DOT&E report are well understood and have been resolved in partnership with the F-35 Joint Program Office or have an agreed path forward to resolution.'
It said the 'planned modifications and fleet management' of the early contract F-35B aircraft will ensure that they meet the 8,000 hour service life requirement, and promised 'aircraft delivering today incorporate design changes in the build process to ensure they'll meet 8,000 hours or more.'
An Israeli Air Force F-35 Lightning II fighter jet
Role: Stealth multirole fighter
First flight: December 15, 2006
Unit cost (not including engine):
F-35A - $98million
F-35B - $104million
F-35C - $116million
Number built: 115 (as of November 2014)
Max speed (F-35A): 1,930kph
With a current development and acquisition price tag already at $379 billion for a total of 2,443 F-35 aircraft - most destined for the US Air Force - the F-35 is the most expensive plane in history.
Once servicing and maintenance costs for the F-35 are factored in over the aircraft's lifespan through 2070, overall program costs are expected to rise to $1.5 trillion for the US alone.
The Marine Corps plans to buy a total of 353 F-35Bs, and 67 F-35Cs,