- Even US Marines Still Don’t Know When Their F-35Bs Might Literally Fall Apart In The Sky
- All F-35s Require Repairs, Modifications to Design and Retrofits – DOT&E
- Persistent Cracks in Bulkheads and Other Components Reported in Tests
- Other Issues Too
PROBLEM IN A NUTSHELL :
You come across any American on social media, and they will always keep driving home the point that F-35s are the only real aircrafts that mankind has ever produced. While the truth is that after decade of flying F-35s, even US Marines still don’t know when their STOVL-variant F-35B might literally fall apart in the sky, if a US report is to be believed.
F-35Bs owe their structural woes, in all likelihood, to a massive effort early in the Joint Strike Fighter’s development to cut the weight of the aircraft, in particular that of the B variant. So beginning in 2004, a group of engineers at Lockheed Martin called the STOVL (Short Take Off/Vertical Landing) Weight Attack Team, or SWAT, found ways to shave more than 2,700 pounds off the Marine Corps’ F-35B version. They trimmed 1,300 pounds from the F-35A and F-35C types, too.
As per ambitious claims of the manufacturers, F-35s are supposed to have a service life of approximately 8000 flight hours, which is basically how long an F-35 Joint Strike Fighter will last before it’s no longer airworthy. By comparison service life for earlier generation F-18s was 6000 flight hours. But now a series of durability tests, which are still on, have shown that F-35Bs in particular have nowhere near service life as preposterously claimed. In fact, inspectors have not yet formally certified any of the three variants of F-35 as having an approximately 8,000 flight hour-long service life.
So far the ground tests have found some ominous discoveries which include that all F-35s that we see flying around, require repairs, modifications to design and retrofits to sustain themselves.
These tests which reported of persistent cracks in bulkheads and other components, along with other issues, raise serious questions that the weight reduction programme which was projected to be crucial at the time of the development of the aircraft earlier on, how much actually got sacrificed in that programme to meet those targets.
TESTS TO CHECK THE STRUCTURAL STRENGTH OF F-35 and DOT&E REPORT
On June 6, 2018, the F-35 aircraft, an A model, arrived at Wichita State University’s National Institute for Aviation Research, or NIAR, as part of the Joint Strike Fighter program’s durability testing regimen. Manufacturer Lockheed Martin had sent the jet from its Fort Worth plant to the research facility so that specialists could tear it down and inspect its internal structure to determine whether it had adequately withstood earlier tests.
So far, while the U.S. Air Force’s F-35As and U.S. Navy’s F-35Cs look to be as durable as expected, but tests on an example of the U.S. Marine Corps’s F-35B have exposed more serious issues.
As part of the F-35 programme, aircrafts undergo exhaustive durability ground testing to validate the structural integrity of the airframe to withstand a variety of maneuvers it will experience throughout its lifetime.
This isn’t the first time NIAR has helped analyze the results of structural and durability tests on F-35 aircraft. In August 2017, the facility received an F-35B model for inspection.
Lockheed Martin has built a total of six ground test aircraft-articles, two of each of the three F-35 variants, to support these experiments and has been actively stress and fatigue testing the airframes since 2009. The company and its subcontractors have used a host of different test stands and other equipment to drop and otherwise simulate typical operations and maneuvers that the aircraft will experience during its expected life cycle.
The U.S. military’s central Joint Program Office (JPO) for the Joint Strike Fighter has mandated that testing put each type of jet through testing that simulates the equivalent of three full life cycles, or 24,000 flight hours.
This doesn’t mean that each one of the test F-35s will go through that full amount of abuse or that contractors can’t perform normal, expected repairs and preventive maintenance during the experiments. The aim is to simulate typical use, not simply shake the airframes apart. Lockheed Martin has set aside one of each three types specifically for ground fatigue testing. While the other three aircrafts (one of each type) have gotten subjected to different kinds of stress tests, including getting shot at to see how the airframe might hold up in combat.
The F-35A that arrived at NIAR in June 2018 had just finished the third cycle of tests for that variant. The F-35C was slated to finish its final round of testing in December 2017, but it is unclear if that has occurred and when analysis of the results might begin.
“For all variants, this testing led to discoveries requiring repairs and modifications to production designs and retrofits to fielded aircraft,” the Pentagon’s Office of the Director of Operational Test and Evaluation, or DOT&E, reported in its most recent annual review of the programme.
But while the F-35A and C variants look set to meet the stated durability goals, the Marine Corps’ F-35B has had considerably more trouble. The F-35 JPO suspended durability testing on that variant in February 2017 after one of the two test aircraft-articles finished the second simulated life cycle, according to DOT&E.
Due to the significant amount of modifications and repairs to bulkheads and other structures, the program declared the F-35B ground test article was no longer representative of the production aircraft, so the JPO deemed it inadequate for further testing,” the Pentagon testing office’s report noted. “The program canceled the testing of the third lifetime with ( the F-35B known as )BH-1 and made plans to procure another ground test aircraft-article, but has not yet done so.”
But now, there is a very real concern that the B variant may not meet the 8,000 flight hour target. These jets may have a shorter service life than the other types “even with extensive modifications to strengthen the aircraft,” DOT&E warned.
PROBLEMS WITH WHEELS of F-35 B :
On top of that, the F-35 B versions are having serious problems with the durability of their wheels specifically. Unlike the F-35As and Cs, the B models have the ability to take off and land vertically, which requires tires that are at the same time durable enough for a conventional landing and soft enough to cushion the jet when it comes straight down.
As it stands now, ground crews have to change the tires, on average, after fewer than 10 full-stop conventional landings, which is less than half the target number. Lockheed Martin has reportedly sourced a possible replacement tire design, but will only begin testing it sometime in late 2018
WHY THESE TESTS ON F-35 ARE IMPORTANT :
Ensuring that the jet’s airframe, as well as other ancillary components, last as long as they’re supposed to, is extremely important for both safety and sustainment reasons. Without an accurate understanding of when the planes will literally fall apart, the U.S. Air Force, Navy, and Marines Corps, as well as foreign operators, could risk putting pilots in the cockpit of aircraft that simply aren’t airworthy.
It is also an essential component for long-term planning with regards to sustaining the F-35 fleets since these tests will provide additional data on what components are most likely to fail and when. This, in turn, can help give an early sense of what portions of the airframe might need an overhaul or outright replacement, and how much that might cost, during any service life extension program down the road.
The oldest members of this fleet of aircraft, which now numbers more than a dozen in total, have been flying for more than a decade already for testing purposes.
As of yet, inspectors have not yet formally certified any of the three versions as having an approximately 8,000 flight hour-long service life.
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Article Originally appeared on The drive
