Mudd, Boomer, Snipe Here's an article with some numbers in it. Now we're getting somewhere. Enjoy.
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Possible JSF 'Re-sequencing' Decision To Come Soon (Posted: Friday, February 20, 2004)
[Defense Daily, Feb. 20, 2004]
By Sharon Weinberger
A possible decision to move the bloated Marine Corps version of the Lockheed Martin [LMT] F-35 Joint Strike Fighter (JSF) to the end of the procurement line is being considered, although the preference is to keep the current order for the aircraft's three versions, according to a senior Navy official.
At recent senior-level meetings with Pentagon officials and representatives of foreign partners to discuss the JSF program, a number of options were put on the table, including the possibility of re-sequencing the current order of the three JSF variants, according to John Young, the assistant secretary of the Navy for acquisition, research an development.
Speaking with reporters at the Pentagon on Tuesday, Young said, "I think it is a viable option to keep the current sequence with a slip," but, he added, "It could be [an option], and it requires some discussion with allies, to re-sequence."
At present, the Pentagon plans to produce the conventional takeoff and landing (CTOL) version for the Air Force first, followed by the Marine Corps short takeoff and vertical landing (STOVL) version, and finally, the Navy's carrier variant (CV). The British Ministry of Defense is planning to buy the STOVL version, although its new carriers could potentially accommodate the Navy's CV variant.
Under the revised option being considered, the STOVL version would become the last version produced, a plan that would significantly impact the Marine Corps and British buys.
"The initial pass was that allies were comfortable with and could manage either option," Young said, but that their preference was to keep the current sequence.
Young said that the U.S. service chiefs are expected soon to meet with Michael Wynne, the Pentagon's acting acquisition chief, to make a final decision on the options.
"That decision is going to be made here shortly," Young said.
While pushing back the STOVL is an option, cancellation is not, he insisted. "I can tell you several allies said they couldn't live with that," Young told reporters. "I don't see that as an option within the Department."
One of the driving forces behind the current debate over the JSF is the Pentagon's acknowledgement that all three versions of the aircraft are overweight--the STOVL version most severely. To address this problem, the Defense Department decided to slip the program a year and added about $5 billion to cover the additional development costs.
Young said that at present the STOVL version is 3,400 pounds over its initial operating capability (IOC) target weight of 30,500. The CTOL is 2,350 pounds over its target IOC weight of 27,100, and the CV is 2,300 over its target of 30,700. Each version of the aircraft has built-in margins that can accommodate extra weight, Young emphasized.
The CTOL could be 1,480 over its target weight, the CV 1,370 over and the STOVL 2,350 over. After that, however, any extra weight could compromise the aircraft's ability to meet key performance parameters. The biggest problem is with the STOVL version, Young acknowledged. The CTOL and CV version could "complete their development today" and not face any significant problems. "STOVL is a slightly different story," he added.
Right now, the STOVL is about 10 nautical miles short of its range target because of the weight problem. Another issue is with vertical landing, which is set at a target height of 550 feet. "Right now, it's approximately 815 feet," Young said.
The STOVL also is falling short on its set parameters for how much ordnance it should be able to bring back from a mission, he said. These are a few of the examples where the STOVL is not meetings its objectives, according to Young.
"It's not that they're not achievable," he said, but "there is more angst there."
Young said there are three options for dealing with the STOVL weight problem: redesign, change the way the aircraft is operated, or change the requirements. "In fact, you can reduce that 815 feet by 75 if you change the horizontal tail settings at takeoff from the amphibious ship," he said. "That's pretty easy."
It's also possible to increase the STOVL's thrust, although he said he'd rather save that option as a reserve for future aircraft growth. Finally, the requirements could be changed. But "I'm not prepared to say right now that we need to change any of the requirements," he said.
In total, the development program has grown by about $7 billion, Young acknowledged. Five billion dollars is for the one-year program slip, which is mostly because of cost growth.
The other funds added--a total of about $2 billion--are $750 million for anti-tamper technology to protect the plane from reverse engineering, $200 million for more operational tests on the Air Force version, $150 million for new or changing requirements, and $1 billion to accommodate commonality requirements among the international versions of the JSF.
The Air Force, Navy, Marine Corps and United Kingdom's Royal Air Force are planning to buy more than 2,500 of the F-35 fighters, and additional foreign military sales could potentially double that number.
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The weight numbers are what interest me most. My estimates are about 3000 lbs <u>lighter</u> for the empty weights of every version. This is very bad news for the STOVL but probably tolerable for the other two versions. I don't know what to make of the reference of a "target height of 550 feet". Something is garbled here. Perhaps they are confusing the STOL takeoff run with height? Maybe they are talking about a short landing run with partial wing lift.
Edited by - a10stress on Feb 20 2004 1:07 PM
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