Earlier challenges:
Lockheed F-35 Fighter Has ‘Design Flaw’ in Wing Part, Pentagon Tester Says
By Tony Capaccio
September 01, 2011 2:49 PM EDT
Two of three models of
Lockheed Martin Corp. (LMT)’s F-35 jet have a “design flaw” that reduces the expected life of a wing structure to 1,200 hours, which is “significantly less than” the expected 8,000 hours, according to the U.S. Defense Department’s testing office.
The “defective” aluminum beam was detected in November on Air Force and Marine Corps test aircraft after an unrelated bulkhead crack surfaced in the Marine Corps model, the office said. The Air Force plans to buy 1,763 of the 2,443 total in the $382 billion U.S. program, the Marines 371.
The flawed part is the forward root rib, an aluminum beam at the forward-inboard corner of the wing that supports a fuselage fairing panel on the Joint Strike Fighter’s leading edge flap, according to Lockheed.
“Structural analysis predicted” that the root rib will have “less than the desired fatigue life,” Pentagon Director of Operational Test and Evaluation Michael Gilmore said in an e- mail statement. “Its short predicted life relative to the stated requirement is a design flaw,” he said.
The heretofore undisclosed flaw underscores the potential for additional cost growth and schedule delays on the Pentagon’s largest weapons program. Previous problems caused former Secretary of Defense
Robert Gates to put the jet into an extended development phase not scheduled to end until 2016, four years later than the original schedule.
Wing Won’t Fail
The issue is one of long-term durability that, were the part not fixed, would add to maintenance and support cost. A preliminary Pentagon estimate already pegs F-35 operating costs at as much as $1 trillion, based on a model used by 107 squadrons at 50 sites through 2065, according to Lockheed.
The F-35 program office and Lockheed Martin have conducted a safety assessment and concluded that a root rib failure would not lead to wing failure, F-35 program spokesman Joseph DellaVedova said in an e-mail.
“This is not considered a serious issue,” DellaVedova said. The program office and Lockheed have developed retrofits and new production improvements designed to extend the beam’s life and correct “durability deficiencies,” he said.
“Resolving durability test findings is a well understood process,” he said. Durability testing is conducted early “to avoid costly sustainment later,” he said.
The
Air Force’s principle military deputy for acquisition, Lieutenant General Mark Shackelford, said in an interview today the “unanticipated bill” for the fixes will likely come from program funding.
Retrofits Planned
The root rib must be redesigned for future production aircraft, Gilmore said. Inspection and repair procedures are being created for the existing test and production aircraft, Gilmore said.
DellaVedova said in an e-mail statement that about 30 Air Force and 30 Marine Corps versions will be retrofitted. A new design will be incorporated on the assembly line in the upcoming fifth low-rate production contract. The Navy aircraft carrier version does not have this durability issue, he said.
Lockheed Martin spokeswoman Laurie Quincy said the F-35 program office statement speaks for the company.
Shackelford said “while you don’t want to have that type of discovery, it’s a fact of life when you are building new aircraft.”
The defect “is not serious enough to be a danger of a loss of a wing -- not a catastrophic failure,” said Shackelford, a former F-22 test pilot. “But there will be some flying-hour limit,” on current jets and “inspections to monitor that structural member. That has some implication in terms of our maintenance work on the aircraft.”
‘Difficult’ Fix
Gilmore said “it remains to be seen how disruptive” retrofitting aircraft will be to the ongoing flight test and field operations. “The needed modification is understood to be a difficult and complex process,” Gilmore said.
“Little durability testing has actually been completed; therefore, more discovery is possible,” Gilmore said.
Aircraft produced with the original root rib “must be inspected periodically” and have required repair before approximately 1,000 flight hours, Gilmore said.
Durability testing of the wing area was resumed in May but halted last month for about a week when a crack was discovered in a predicted area of the root rib after about 2,800 hours of testing, DellaVedova said. The test was resumed a week later and is ongoing for completion of 3,000 hours, he said. The crack is being monitored.
To contact the reporter on this story: Tony Capaccio in Washington at
acapaccio@bloomberg.net
To contact the editor responsible for this story: Mark Silva at
msilva34@bloomberg.net
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January 15th, 2013 | Posted by
WorldTribune.com
Pentagon reports major defects in all F-35 variants
Special to WorldTribune.com
WASHINGTON — The Defense Department has reported additional flaws
in the Joint Strike Fighter, sought by Israel and Turkey.
The Pentagon’s Office of Operational Test and Evaluation asserted that
all three variants of the JSF contained major flaws. In a report submitted
to Congress, Defense Undersecretary Michael Gilmore said the F-35 was being
hampered by design and production defects that emerged in 2012.
An F-35A fighter plane arrives at Eglin Air Force Base in Florida. /Lockheed Martin
“The lag in accomplishing the intended 2012 flight testing content
defers testing to following years, and in the meantime, will contribute to the program delivering less capability in production aircraft in the near term,” the report said.
The report, slated for release on Jan. 15, was submitted to Congress
amid the refusal by NATO members to order JSF. On Jan. 11, Turkey announced that it was delaying plans to procure its first two F-35As. So far, Israel, whose procurement of 19 aircraft was financed by Washington, has been the only foreign client that followed through on its initial order.
The Pentagon report said the F-35 was found to be vulnerable to an
outbreak of fire. Gilmore said the removal of protection systems from JSF in 2008 increased vulnerability to a Polyalphaolefin, or PAO, blaze by 25 percent.
“The program’s most recent vulnerability assessment showed that the
removal of fueldraulic fuses, the PAO shutoff valve, and the dry bay fire
suppression, also removed in 2008, results in the F-35 not meeting the
Operational Requirements Document requirement to have a vulnerability
posture better than analogous legacy aircraft,” the 17-page report, titled
“FY2012 Operational Test & Evaluation,” said.
The report cited a halt in testing of the F-35B short-takeoff and
vertical landing variant, sought by the U.S. Marine Corps. The Pentagon said
the tests were suspended in December 2012 when multiple cracks were found on
the underside of the fuselage. Other F-35 were said to have developed cracks
in their wings.
Other tests were canceled in 2012 because of aircraft limitations that
prevented the extended use of the afterburner. Other factors included higher
than expected loads on weapon bay doors and deficiencies in the
air-refueling system.
The report also cited delays in software development for the F-35.
Flight tests were said to have been hampered by delays in software or
incomplete software.
The F-35′s helmet-mounted display system, designed and developed by
Israel’s Elbit Systems, was also deemed deficient. The report cited
difficulties in night-vision as well as inadequate imagery and recording.
“Boresight alignment between the helmet and the aircraft is not
consistent between aircraft and requires calibration for each pilot,” the
report said. “Finally, a recently discovered technical problem referred to
as ‘green glow’ has been experienced when light from the cockpit avionics
displays leaks into the helmet-mounted display and degrades visual acuity
through the helmet visor under low ambient light conditions. The test team
is planning additional, dedicated ground and flight testing to address these
technical problems.”
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F-35 JOINT STRIKE FIGHTER NOT READY FOR COMBAT UNTIL AT LEAST 2019, GAO SAYS
U.S. AIR FORCE/AP
The $397 billion F-35 Joint Strike Fighter will not be ready to go into operation until at least 2019, 23 years after the Pentagon signed a contract in 1996 with Lockheed Martin to produce just fewer than 2,500 of the aircraft for the Air Force, Navy and Marine Corps, according to a new
report.
Initial operational test and evaluation -- or IOT&E -- testing of the F-35, the most expensive Defense Department procurement in history, is scheduled to begin in 2017 and run through 2019, the Government Accountability Office said. These tests will “evaluate the combat effectiveness and suitability of the aircraft in an operationally realistic environment,” GAO said.
These tests will determine if the plane can achieve “key performance parameters [that] are critical to the F-35 meeting the warfighter’s operational requirements. They include measures such as range, weapons carriage, mission reliability and sortie rates. These parameters also cannot be fully verified until the end of IOT&E in 2019,” GAO said.
If the F-35 passes the tests, then Defense can give Lockheed the green light to proceed with production of combat-ready aircraft, GAO said.
Software development for the F-35 presents a “significant challenge” for Lockheed and the Pentagon, with completion of the final version of some 9.5 million lines of code not expected until 2017, GAO reported.
Lockheed and the Pentagon’s F-35 program office recently took steps to improve software management and output, including automated processes which have reduced the time to build and release new software to testing to 30 hours from 187 hours.
But, the report said, “A substantial amount of integration and test work remains before the program can demonstrate full war fighting capability.”
The first major block of software, which supports training flights, was “largely completed” in 2012, GAO said, but it did not fully meet expected requirements for a helmet-mounted display, instrument landing capabilities and the
Autonomic Logistics Information System developed to predict and diagnose maintenance and supply issues, automating logistics support processes.
The software block planned to provide limited combat capabilities fell behind schedule last year due to “integration challenges” GAO did not specify and the reallocation of resources to fix defects in the first block of software. It won’t be completed until 2015
Lockheed has “made little progress” on development of the final version of the software which will fuse radar, electro-optical target systems, electronic warfare systems and communications and navigation equipment, the GAO said.
Progress on these “software intensive” mission systems “was limited by contractor delays in software delivery, limited capability in the software when delivered, and the need to fix problems and retest multiple software versions,” the GAO report said. Development and of the most complex systems – which integrates data from subsystems and displays information to the pilot are challenges still faced by Lockheed and the Pentagon, GAO said, with software to support fusion requirements not expected for completion until 2016.
The GAO report echoes criticisms in a January
report to Congress by J. Michael Gilmore, director of operational test and evaluation for Defense. That report said the Pentagon has made “virtually no progress in the development, integration, and laboratory testing” of software for production versions of the F-35.
Report: Technical Malfunctions Delaying Israel Air Force’s Use of New F-35 Fighter Jet
JANUARY 24, 2014 11:36 AM
2 COMMENTS
Author:
Gidon Ben-zvi
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F-35 IsraelF-35 malfunctions PentagonF-35 Pentagon IAFfighter jet Israel PentagonLockheed Martin Israel Air ForceU.S. Marine Corps F-35
An F-35 stealth jet on a test flight. Photo: Wikipedia.
Due to a series of technical failures, Israel’s receipt of new Lockheed Martin F-35 fighter jets is expected to be delayed, Israeli daily
Walla reported on Thursday.
A report that was recently made public by The U.S. Department of Defense, said the F-35 has been plagued by software problems and issues related to performance and reliability,
Walla said. As a result, the jet fighter’s incorporation into the U.S. Marine Corps has also been pushed back 13 months, according to the report.
In October 2010, Israel finalized a deal for the acquisition of 19 F-35 aircraft for 2.75 billion dollars. Originally, the plan was for the jets to be delivered to the Israel Air Force in 2015,
Wallasaid.
The F -35 boasts a wing span of over 10 meters, a carrying capacity of 14 tons and a cruising range of more than 1,600 km.
This week’s announcement is not the first time that Lockheed Martin’s newest model fighter jet has faced glitches. According to Israeli daily Ma’ariv, in October 2013 the Pentagon discovered over 300 defects related to the production process of the F-35. At the time, the Pentagon published a report saying that these issues could well impair the fighter plane’s very ability to perform, Ma’ariv said.
A year ago, the Pentagon published another report that described a flight test conducted on the F-35 in which the test pilots reported that the aircraft had serious bugs in its field of vision, radar system, touch screen system and the functionality of the pilot’s helmets.