All grounded F-35s to resume flying

 

The Pentagon has cleared all grounded F-35s to resume flight testing after discovering the root cause behind the March 9 twin generator failures of an F-35 Joint Strike Fighter (JSF) airplane.

The program office said Friday night that faulty maintenance procedures were found to have caused the in-flight failure of the engine generators of the F-35 JSF fighter.

This month, a U.S. Air Force F-35A test aircraft, numbered AF-4, suffered a failure of the generators during a test flight from Edwards Air Force Base. The test pilot was able to use the backup electrical generator to return safely to base.

The configuration of the generator on AF-4 and other, newer F-35s was different than the original installation on the first test aircraft, and the problem was traced to the newer, or alternate, configuration.

Test aircraft with the earlier configuration – three F-35As and four Marine Corps F-35Bs – were cleared on March 14 to resume flight operations.

Three other test aircraft – AF-4, BF-5 and CF-1, the first Navy F-35C - remained grounded, along with the first two low-rate initial production F-35As, while the investigation continued.

According to the program office, the investigation revealed that the maintenance procedure for the alternate engine starter/generator configuration allowed excess oil in the generator’s lubrication system.

Source: DefenseNews

GE CEO: To keep up fight for F-35 engine

General Electric Co. Chairman and CEO Jeff Immelt sent a letter Wednesday morning to company employees promising to continue the fight to fund an alternate engine for the F-35 Joint Strike Fighter.

Last week’s vote in the House of Representatives to kill the engine project “is not the end of the process,” Mr. Immelt wrote in the letter to GE Aviation employees. He said the company “will continue to press our case in the U.S. Senate and elsewhere” for the engine, which is being developed by GE Aviation at an Ohio facility.

The primary engine supplier is Pratt & Whitney, a unit of United Technologies Corp. GE has been developing a second engine with Rolls Royce PLC at a facility in a suburb of Cincinnati; it has argued that a second engine would lower the long-term costs of the Joint Strike Fighter program by putting competitive pressure on Pratt & Whitney.

Secretary of Defense Robert Gates had tried repeatedly to stop Congress from funding the F35 engine, which he has described as emblematic of wasteful government spending. Last week’s vote was a major setback for GE, as Republican budget hawks teamed up with Democrats to back a White House call to end the program.

- Wall Street Journal

Read related story:

Gates increases scrutiny of costly F-35 program

Revised F-35 plan calls for 6 more years of testing

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GE/Rolls-Royce has 15 percent more thrust than JSF’s Pratt and Whitney engine

Revised F-35 plan calls for 6 more years of testing

 

Details of the revamped F-35 Joint Strike Fighter program are emerging and showing that, despite more than nine years of work, almost six years of challenging development and testing still lie ahead for the Lockheed Martin-led project.

Both flight testing and software development have been re-planned using industry-standard productivity rates rather than the aggressive—and unachievable—assumptions on which the original program was built. This means many more sorties to re-fly flight-sciences test points and for regression testing of mission-system software changes.

The re-plan adds 2,000 flights to the program—for a total of 7,800, just 600 of which have been completed—and extends development testing to October 2016. In addition to more re-fly and regression flights, the new plan adds sorties for test-pilot training and builds in a 500-flight margin for unexpected flight-sciences and mission-system issues.

Of the 8 million lines of code on the aircraft, “we have 4 million to do, but we still have four years of development,” says Eric Branyan, deputy general manager of the F-35 program.

In F-35 parlance, Block 0.5 provides basic “aviate and navigate” capabilities, Block 1 introduces onboard sensor fusion, Block 2 integrates weapons and data links, and Block 3 provides the full capability planned for development.

Block 1 hardware began flight tests on mission-system development aircraft in April 2010, and is now the baseline through low-rate initial production (LRIP) Lot 4. While LRIP 1 and 2 aircraft will still be delivered with Block 0.5 functionality to begin training, this is now part of Block 1A running on the new hardware.

In addition to increasing the re¬sources for flight tests, the re-plan essentially decouples flight-sciences work on the three variants, he says. This is intended to overcome the impact of delays in testing the short-takeoff-and-vertical-landing (Stovl) F-35B on the smoother-running conventional-takeoff-and-landing F-35A and F-35C carrier variant.

The Joint Program Office (JPO), meanwhile, says each of the known problems with the Stovl F-35B are “readily solvable through engineering adjustments.” Among the issues being worked on are lift-fan clutch heating, thermal expansion of the lift-fan driveshaft and roll-post heating. Additionally, “selective redesign” of the lift-system doors is needed to “increase durability,” the JPO says.

The Pentagon will seek an additional $4.6 billion in its fiscal 2012 budget for the replanned program. This includes funds “to address known discrete improvements to include propulsion lift system, durability and structuring testing shortfalls, training systems, pilot-vehicle interface upgrades and others.”

- aviationweek.com

20 F-35 JSF Offered To Israel By U.S.

F-35 Joint Strike Fighter aircraft

The Israeli government is being pressed by its defense establishment to accept a U.S. offer of 20 F-35 Joint Strike Fighters in return for a renewal of the moratorium on West Bank settlement-building.

Eager to resume the stalled Israeli-Palestinian peace talks, Washington is offering the F-35s, valued at $3 billion, if Israel halts the construction that Palestinians cite as a barrier to negotiations. Israeli Defense Minister Ehud Barak confirms the offer was made while the U.S. State Department refused to comment on the said offer. Barak said “In the past, we wanted to procure 40 F-35s but due to budget constraints we could only afford 20.” He adds “Now the U.S. is offering to give us the additional 20 in exchange for a 90-day freeze on settlements.”

The U.S. also pledges to provide Israel with more technology and capability to counter the threat from Iran, veto any anti-Israeli resolution in the United Nations or the International Atomic Energy Agency and sign a defense treaty with Israel if a peace accord with the Palestinians can be achieved.

According to Israeli defense sources, the offer was initially presented in September, as a 10-month moratorium on settlements was about to expire, but Prime Minister Benjamin Netanyahu rejected it. The offer was renewed by U.S. Secretary of State Hillary Clinton in a 7-hour meeting with Netanyahu in New York on Nov. 11. It is assumed that Clinton demanded, in addition to the moratorium, that Israel accept the U.S. guidelines for the negotiations with the Palestinians and remove some objections that have stalled the peace process so far.

This time, Netanyahu asked to receive the U.S. proposal in a presidential letter, which he will put before his cabinet, a move that stirred vocal opposition from his own party and other coalition partners. Barak comments that “Twenty fighters are much more important in the long term than the current political friction between Netanyahu and his party members.”

Without commenting directly on the U.S. offer, Israel air force commander Maj. Gen. Ido Nachoshtan notes that “the F-35s will provide us a significant strategic capability. They have a key role in the building of Israel’s air force in the face of a developing arena.”

Israel signed a $2.75-billion contract in October to buy a first squadron of 20 F-35As, to be financed through U.S. foreign military aid funds and delivered in 2015-17. The 20 aircraft the U.S. are offering now would not be delivered until the end of the decade. Late last week, Israel had not yet received the U.S. letter of commitment.

 

-aviationweek.com

-jsf.mil

LM wants F-22 to have common architecture with F-35

LM's F-22

 

 

Lockheed Martin is looking at revamping several of the F-22‘s most critical systems with hardware from the F-35.The initiative would create a common architecture that links upgrades of the radar, electronic warfare suite and communications, navigation and identification (CNI) system to both aircraft.

LM said the concept requires “significant initial investment”, but “could yield some cost savings in the long term”.

Lockheed developed the F-22 about a decade ahead of the F-35. Both aircraft share the company’s “fifth-generation fighter” slogan, but major subsystems are based on different architectures. So improving hardware or software on the F-35 yields no benefit for the F-22, and vice versa.

No decisions have been made, but Lockheed officials at the F-22 factory are asking if that should change, only 16 months before the production line is shut.

“Say, if we want to add something to [the F-22] CNI suite, F-35 could take that wholesale with minimal modifications,” says Jeff Babione, vice-president and deputy general manager of the F-22 programme. “So you’ll see this bouncing back and forth where F-22 develops something for F-35, and F-35 develops something for F-22.”

Another potential example is the integration of the multifunction airborne data link (MADL), a narrowband channel designed to pass data between stealth aircraft such as the F-35, F-22 and the Northrop Grumman B-2A bomber.

The US Congress has criticised the US Air Force over the high cost of integrating MADL on the F-22, even after making a similar heavy investment for the F-35. The USAF has recently withdrawn MADL from the Increment 3.2 upgrade programme for F-22, delaying the start of integration until fiscal year 2014, Babione says

The two options under review are to add 2,000h or 4,000h to the airframe’s service life, Babione says. Lockheed plans to submit its results by end-year.

- flightglobal -

Northrop Grumman’s DAS Test with F-35 a Success

During a routine flight test conducted aboard Northrop Grumman Corporation’s BAC 1-11 test bed aircraft, the company’s AN/AAQ-37 Electro-Optical Distributed Aperture System (DAS) for the F-35 Lightning II Joint Strike Fighter successfully detected and tracked a two-stage rocket launch at a distance exceeding 800 miles.

Dave Bouchard, program director for F-35 sensors at Northrop Grumman, said “The DAS could fill critical capability gaps in the area of ballistic missile defense (BMD).” He also said “We have only scratched the surface on the number of functions the F-35′s DAS is capable of providing. With DAS, we’ve combined instantaneous 360-degree spherical coverage, high frame refresh rates, high resolution, high sensitivity powerful processors and advanced algorithms into a single system. The number of possibilities is endless.”

An operational DAS system is comprised of multiple DAS sensors whose images are fused together to create one seamless picture. DAS successfully detected and tracked the rocket during a nine minute, two-stage, flight period from horizon break until final burnout through multiple sensor fields of regard. Unlike other sensors, DAS picks up targets without assistance from an external cue. Because DAS is passive, an operator does not have to point the sensor in the direction of a target to gain a track.

Bouchard adds that “The DAS software architecture already includes missile detection and tracking algorithms that can be applied to the BMD mission.” He also claims that “The results of the flight test were extraordinary. We found that the data gathered during this flight validated our performance predictions. In fact, we knew we could have seen the rocket at a longer distance.”

The AN/AAQ-37 DAS is a high resolution omni-directional infrared sensor system that provides advanced spherical situational awareness capability, including missile and aircraft detection, track and warning capabilities for the F-35 Joint Strike Fighter. DAS also gives a pilot 360 degree spherical day/night vision, with the capability of seeing through the floor of the aircraft. Northrop Grumman is now exploring how the existing DAS technology could assist in several additional mission areas, including Ballistic Missile Defense and irregular warfare operations.

Northrop Grumman’s Electronic Systems sector designed and produces the F-35 Joint Strike Fighter AN/AAQ-37 DAS. The DAS F-35 software that includes algorithms for all JSF functions was delivered to Lockheed Martin Corporation earlier this year. Northrop Grumman also designed and produced the AN/APG-81 AESA radar system, and designed and produces the F-35‘s Communications, Navigation and Identification (CNI) system.

- asdnews.com

Israel in talks to build wings for F-35s

Last Monday, an Israeli official who declined to be names said that Israel is in talks to build the wings for about a quarter of the United States’s new F-35 stealth fighter aircraft. The Israeli official said state-owned Israel Aerospace Industries would build the wings. “We are in advanced talks for the IAI to produce around 800 sets of wings,” he told Reuters.

Lockheed Martin currently plans to build some 3,200 F-35s costing about $96 million each. Lockheed Martin declined to comment on the details of a possible deal involving the aircraft, also known as the Joint Strike Fighter (JSF).

Israeli Defense Minister Ehud Barak approved in principle the purchase of 20 of the radar-evading fighters, in a deal worth $2.75 billion, earlier this month.

Israeli and U.S. officials expect final approval of that deal by the end of September. The planes would be delivered in 2015-2017. The cost of the purchase would be covered by an annual U.S. defense grant of $3 billion.

Israel would be the first foreign country to sign an agreement to buy the F-35 outside the eight international partners that have helped to develop the plane. Israeli and U.S. officials with knowledge of the deal said Israel has an option to buy a further 55 aircraft.

An Israeli official said reciprocal purchase deals worth $4 billion had been secured for Israeli companies for their participation in the plane’s manufacture and might be increased to $5 billion although it would be conditional on Israel exercising its option to buy the additional 55 planes.

The F-35 is designed to avoid detection by radar and could play a role in any Israeli effort to knock out what it regards as the threat to its existence posed by Iran’s nuclear program. Tehran denies Western and Israeli allegations that it is trying to produce atomic weapons.

- planenews.com