<i> Speaking of progress. Here's some published stuff from Aviation Leak. It's good to hear they are not building the overweight configuration of the STOVL.</i>
<b>JSF Team Shifts Course on First STOVL Version</b> (Posted: Thursday, September 09, 2004)
[Aviation Week & Space Technology, Sept. 5, 2004, page 38]
<b>Joint Strike Fighter team updates software, flight test strategy</b>
Robert Wall
Washington
F-35 Joint Strike Fighter managers have again tweaked project plans, this time to speed up testing of a production-representative short takeoff and vertical landing version of the multi-role fighter.
Resumption of Stovl JSF flight testing is planned for late 2007, this time in a production representative configuration that will differ significantly from the prototype. Credit: LOCKHEED MARTIN (Click on photo for an enlarged view)
Moreover, representatives of the Lockheed Martin-led JSF industry team are updating the program's schedule and software plans for presentation to senior Pentagon leaders in October. The meeting could put an end to the turmoil the program has been in for more than a year, since developers discovered the Stovl model was more than 3,000 lb. overweight.
When the team initially regrouped after the weight problem was found, it determined the first two of 14 flight test aircraft built during the system design and demonstration phase would have to be in the "heavy" configuration. But the contractors' so-called Stovl Weight Attack Team (Swat) was able to complete most of its work faster than expected, opening up the opportunity for the first Stovl to be in the "optimized" configuration, says Tom Burbage, Lockheed Martin vice president and JSF general manager.
The switch doesn't come without a price. First flight of B1, the first Stovl JSF, would now take place about three months later, approximately late 2007. However, Burbage points out the change eliminates a lot of engineering activity that would have gone into designing a one-off "heavy" Stovl airplane. Moreover, it should make initial flight test data more relevant.
During an informal review last month, the Pentagon gave the green light to the strategy.
The "optimized" B1 will feature a smaller bay for the Stovl version. It has been shrunk about 14 in. and will limit that version of JSF to carrying two 1,000-lb. bombs--the other models will still carry 2,000-lb. bombs. British military officials indicated some unease about the move, but Burbage says the design change was put to a vote. All Stovl customers--the U.S., the U.K. and Italy--approved the decision. B1 will also feature a redesigned top inlet used during hover and a smaller diameter lift nozzle. Both changes make the engine more efficient and help mitigate weight.
Production of the B1 will begin in late 2005 with the fuselage section at Northrop Grumman, says Steven Briggs, Northrop Grumman's JSF manager.
The weight reduction effort has shaved more than 2,700 lb. from the aircraft, and generated additional savings by relaxing performance requirements. As a result, the program has weight margin going forward, Burbage says.
Between now and October, when the next formal JSF review takes place, developers hope to have detailed plans for the various program elements in synch with the new approach. For instance, the extra engineering time has put more pressure on the flight test schedule, which is now being scrubbed. Additionally, the content and schedule of avionics software blocks are being redefined. Some software functions initially planned need updating because technology has evolved, and others are being rearranged to conform to the new program schedule.
A lesson JSF has taken from the F/A-22's troubled software experience is to locate all integration laboratories at a single site. Moreover, managers have identified possible times when those facilities will be in heavy demand, and they are trying to determine if more capacity can be made available somewhere else.
Another concern of the program was figuring out how to do all the wiring in the confined space of the JSF, particularly the Stovl with its lift fan. But that has been resolved, Burbage says. And some wiring that wasn't needed at certain weapon stations has been eliminated to save weight.
Production of the first aircraft, the "heavy" A1, is already well underway, Briggs notes. Northrop Grumman expects to deliver the first fuselage to Lockheed Martin next year, where it will be mated with the aft and forward fuselage section and the wing. Even though it is still early in the program, the company already has set up a multi-shift production process that runs seven days. The arrangement of two 10-hr. shifts worked Monday through Thursday, and two more Friday through Sunday gives the program surge capacity should schedule pressures build, while at the same time eliminating the need for costly overtime, Briggs says.
The center fuselage is furthest along. BAE Systems last week formally inaugurated its aft fuselage production line, says Tom Fillingham, the company's vice president and JSF manager.
Production so far appears to be moving ahead at a good pace. Burbage says the often complex process of establishing an enterprise-wide digital design system is paying dividends.
Looking forward, the program is essentially focused on two paths, managing international agreements and building the aircraft. In 2006, U.S. officials hope to have agreements with the partners on future production plans. Dealing with issues of training and global sustainment--including technology release for aircraft maintenance--also have to be addressed.
The other path focuses on executing the development program. Critical design review (CDR) for the first "optimized" conventional takeoff and landing aircraft is set for March 2006, concurrently with B1. But government officials would like to accelerate that by a few months. CDR for the first carrier version won't occur until 2007.
The exact production flow in the current phase also is still being devised. After A1 and B1, the program will likely build an additional Stovl aircraft and one or more of the eight non-flying static and fatigue testing versions, before delivering A2.
Burbage notes that progress is also being made on key subsystems, in particular the radar Northrop Grumman is developing and the electronic warfare suite at BAE Systems. Components are already undergoing flight testing on various surrogate aircraft. Despite delays Pratt & Whitney encountered with the F135 Stovl engine, Burbage says the propulsion arena appears to be on track to support the current schedule.
THE CRAPTOR ENGINEERING TEAM <img src=icon_smile_big.gif border=0 align=middle>
"The F-22...It's the poo"
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