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[机型] 美F35“闪电2”专题讨论贴:2018最后一架交付

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waitforcv 发表于 2010-2-10 23:02 | 显示全部楼层
rejions 发表于 2010-2-11 13:10 | 显示全部楼层
工业基础自然有关系,不过工业基础为什么提不高呢?还不是不肯花钱
costrave 发表于 2010-2-10 19:31


土鳖现在才进入重工业化阶段,这就是工业基础滴现状,提升滴资本是这三十年衣服袜子攒下滴第一桶金。
 楼主| speed 发表于 2010-2-11 14:59 | 显示全部楼层
f16的这个加速时间是在什么高度呢?有报道吗?

不同高度大气密度不一样,发动机推力也不一样。

并 ...

costrave 发表于 2010-2-11 00:42


F16好像是在30000英尺的高度,F35不知道,但是我估计测试的条件应该和F16一样,都是30000英尺。
 楼主| speed 发表于 2010-2-11 15:16 | 显示全部楼层
本帖最后由 speed 于 2010-2-11 15:18 编辑
没有可信的资料吗?反正以前看过f35和其他飞机的对比柱状图,跨音速加速性能不算差。

costrave 发表于 2010-2-11 15:06


F16的数据应该没有错,但是具体的数据来源暂时没时间去找了,等以后补上了。


F35的数据是航空周刊根据某些内部消息推测的,具有一定的权威性,同时F35试飞员的说法也能从侧面证明F35的跨音速加速性能不好。
贝尔纳多特 发表于 2010-2-14 17:24 | 显示全部楼层
F35的跨音速加速性能根据航空周刊的报道如下:该机当前布局(代号240-4)的准确性能仍是保密的,但据信具有如下性能:最大飞行速度为马赫数1.67;在3万英尺(9144米)高度从马赫数0.8加速到1.2需61秒;


事实上这个240-4配置是保密的,现在没有消息。事实上航空周刊用的是一个类似的早期240-3配置标准。

The exact performance of the current F-35A configuration -- also known as the 240-4 -- are classified. But a similar earlier standard (240-3) was credited with a maximum speed of Mach 1.67; acceleration from Mach 0.8 to Mach 1.2 at 30,000 ft. in 61 sec.

还有一点不清楚,第一架减重改进后的F-35A(AF-1)是2009年底才开始试飞的,但是这篇文章是在2009年3月份时候登出来的,其中的试飞员感受等等可能来自第一架没减重的F-35A(AA-1),所以还有很多细节不清楚。
贝尔纳多特 发表于 2010-2-14 17:30 | 显示全部楼层
一些视频:



F-35B(BF-1)到达帕图克森河
贝尔纳多特 发表于 2010-2-14 17:30 | 显示全部楼层


F-35B(BF-2)在帕图克森河
贝尔纳多特 发表于 2010-2-14 17:31 | 显示全部楼层


F-35B第一次STOVL飞行
贝尔纳多特 发表于 2010-2-14 17:32 | 显示全部楼层


F-35B第二次STOVL飞行
贝尔纳多特 发表于 2010-2-14 17:32 | 显示全部楼层

英国飞行员Steve Long 成为了第8名驾驶F-35的飞行员
贝尔纳多特 发表于 2010-2-14 17:33 | 显示全部楼层


F-35B(BF-3)首飞
 楼主| speed 发表于 2010-2-20 13:27 | 显示全部楼层
事实上这个240-4配置是保密的,现在没有消息。事实上航空周刊用的是一个类似的早期240-3配置标准。
...

贝尔纳多特 发表于 2010-2-14 17:24


如果光是减重而气动外形不变的话,对跨音速加速性能的影响不大,因为现有的F35的试飞机推重比并不低,但是跨音速的加速性能仍然很差,说明问题不在于机体重量超重,而在于自身的气动设计。

如果240-4布局如同转说中的那样减重2000磅的话,对爬升率和盘旋率的贡献会很大,但是对加速性的影响就比较小。
贝尔纳多特 发表于 2010-2-20 14:20 | 显示全部楼层
AA-1也不是采用240-4布局,那个布局只是验证时候提出一种方案,至于和240-3相近,相近到什么程度,航空周刊没说,也没有说到到底改了哪些地方。所以240-4布局实际上没有试飞过。AA-1的推重比也不是很出色,减重后应该推重比有改善。
 楼主| speed 发表于 2010-2-22 23:10 | 显示全部楼层
F-35 Faces A Troubled 2010

Feb 5, 2010

http://www.aviationweek.com/aw/g ... A%20Troubled%202010

By Bill Sweetman
Washington

Unlike Julius Caesar, the JSF program will survive March. However, it may suffer a couple more wounds to go with those received earlier this year. The Pentagon’s Selected Acquisition Reports (SARs) will be released and are likely to show a critical breach of Nunn-McCurdy cost-escalation limits, leading to a mandatory program review. Also, the Government Accountability Office is due to issue another report on the program. Given the program leaders’ cavalier dismissal of GAO’s earlier warnings, it is likely to be harsh and seasoned with “we told you so.” Before or around that time, another schedule slippage is almost certain.

Under Nunn-McCurdy, if a program’s estimated unit-procurement costs exceed 150% of what was planned at the outset (or “rebaselined” before 2005), the program must be recertified. This means the Pentagon must confirm that it is essential, costs are reasonable and management is in control of costs. The Pentagon also has to provide Congress with the costs of an alternative solution to the requirement—all within 60 days of notification.

The strongest warning yet of a Nunn-McCurdy breach came in a Jan. 19 letter to suppliers from Tom Burbage, executive vice president of the F-35 at Lockheed Martin, and Dan Crowley, Lockheed Martin’s second-most-senior JSF leader. “We are working closely with the U.S. government to avoid a Nunn-McCurdy critical breach if possible,” the letter reads, “though these calculations are subject to factors beyond [our] control, including escalation indices, propulsion costs and the degree to which independent estimates are used for SAR forecasts.”

The last two qualifications are crucial. Propulsion-system costs are still high, and the Pentagon’s plans to cancel the F136 alternate engine from General Electric and Rolls-Royce have been blocked. And since recent independent assessments—from the Navy, the director of operational test and evaluation (DOTE), and the Joint Estimating Team (JET) formed to investigate the JSF program—have been negative, and the program’s repudiation of the 2008 JET report proved premature, it’s almost certain they will be taken into account in the SAR.

The program’s public tone is unworried. Burbage and Crowley assure suppliers that the JSF is “making solid progress.” They say static testing has been completed successfully for the F-35A and F-35B versions, and near- and far-field tests of the full-scale radar cross-section test article are going to plan. Avionics tests demonstrate “unprecedented software stability,” and CATBird tests successfully demonstrated sensor fusion between the radar and electronic warfare systems.

The letter also states that successive system development and demonstration (SDD) test articles (19, including non-flying structural and other test airframes) have been built with less travel work—tasks performed out of sequence—and been more complete at rollout.

These are encouraging statements and projections, but neither reflect visible progress nor sit well alongside the January DOTE report.

Flight testing continues to slip, not only against the current official schedule (which reflects a one-year delay in completion of development testing, and was established in early 2008) but against predictions in September 2009, which called for five more aircraft to fly and the first vertical landing to be performed before the end of last year. Only one test aircraft flew (AF-1, which made two sorties), and the path to vertical landing did not start until January, when BF-1 engaged its lift fan in flight.

The Burbage/Crowley letter says “all development airplanes are expected to be delivered to the flight-test centers over the next year.” But last September, that milestone was due to be reached in the third quarter. AF-1, too, has been grounded for a long period after its first flights: It made three sorties in November, but at presstime had not flown for two months.

DOTE normally takes a critical attitude. The director, Michael Gilmore, reports directly to the Defense secretary. His office’s job is to find problems that have not been reported up the normal acquisition chain. That said, the January report was notable for the number of issues raised and the extent to which it disputed the program’s predictions.

Most important, DOTE predicts that the initial operational test and evaluation (IOTE) will be completed at least 18 months late, “in early to mid-2016.” Moreover, the report says only that this “could occur” if corrective action is taken immediately to extend SDD, add flight-test aircraft and if testing moves at an adequate pace. DOTE points out that the program accomplished only 16 flight-test sorties in Fiscal 2009 (discounting sorties flown by the non-standard AA-1 aircraft) out of 168 tests planned with full-up SDD aircraft. And although CATBird made 55 flights in Fiscal 2009, mission-systems tests started five months late, in March 2009.

DOTE warns of an upcoming problem: The IOTE task is supposed to be performed by the early low-rate initial production (LRIP) aircraft, but many of these will be ordered before flight testing and “the mission capability of the LRIP aircraft and support systems is unclear.”

One reason for this uncertainty is that the program predicts the delivery of functionality—what tasks the aircraft is equipped to perform—rather than performance, or how well they work.

DOTE reported that the completion of testing on all software blocks had been delayed by a year, along with the availability of the first F-35 with mission systems installed (BF-4).

Modeling and simulation, which the JSF team has touted as the secret weapon that will allow the project to be completed on time and on schedule, despite recent history, is at an early stage, says DOTE. The problem is that most of the labs and models have not been accredited—i.e., accepted as valid substitutes for aircraft testing. For this to happen, the report says, the lab performance needs to be verified by “hardware and software-in-the-loop ground and flight tests.” DOTE cautions against using models before they are ready.

DOTE cites a litany of problems, including more clutch heating discovered in last year’s hover-pit tests and software instability. The interservice JSF Operational Testing Team, according to DOTE, says the program “is on track to achieve operational effectiveness requirements but not operational suitability requirements.”

Thermal management remains a problem. The F-35’s systems are cooled by mechanisms that dump heat into the fuel, and a key element is a thermally efficient fuel pump—which circulates fuel at the required rates without adding heat to it—that has had development issues. The pump is to be installed on LRIP 2 F-35Bs and all F-35s from LRIP on.

Development work continues on the F-35’s ejection seat (DTI September 2009, p. 22) and the explosive Transparency Removal System, which is designed to separate the canopy transparency from its frame and break it along its centerline. Sled tests have revealed that as speeds increase the canopy segments do not “fly away” as planned (reportedly separating into shards), and so far the system has been cleared only to 450 kt. equivalent airspeed. A revised system is due to be tested this spring and to clear the aircraft to 550 kt. equivalent airspeed, “the current flight condition at which we have high confidence in the fly-away characteristics.” There is no word on when the system will be cleared to its 600-kt. equivalent airspeed design limit.

One source suggests that JSF may be running into high-angle-of-attack handling problems including “abrupt stall.” Lockheed Martin says that tests have allowed the designers to prevent such a problem “by incorporating design elements and developing fallback options, should the phenomenon appear during flight testing.”

But that flight testing is a long way off. F-35 high-alpha testing will not start before the fourth quarter of 2011—3.5 years after BF-1’s first flight and less than a year before the Marines are supposed to declare initial operating capability (IOC). (In contrast, F-22 high-alpha testing started in August 1999, less than two years after first flight, six years ahead of IOC and before production aircraft had been ordered).

By early 2012, 185 jets are planned to be on order and advance procurement contracts should be signed for 156 more. And the predicted date is still two years out, from a program that hasn’t made a successful two-month prediction since 2008.

Another cloud on the horizon, says DOTE: “F-35C predicted takeoff speeds continue to increase and now exceed tire limits in hot and high-density-altitude environments.” One source calls the F-35C “a looming scandal,” separate from the dire predictions of operating cost issued by the Navy in January. Last month, Goldman Sachs downgraded Lockheed Martin stock from “neutral” to “sell.” “We expect 2010 to be a year of major challenges and constant negative headlines on the JSF program.” Say what you want about Wall Street, they called that one right, and it’s only February.

Photo credit: U.S. Defense Dept.
 楼主| speed 发表于 2010-3-16 18:02 | 显示全部楼层
美官员证实F-35单价将翻倍达到1.12亿美元

2010-03-16 作者:陈宣友 来源:中国航空工业发展研究中心


  据美国《航宇日报》2010年3月12日报道 2010年3月11日,美国国防部采办主管Ashton Carter在国会向参议员称,JSF的平均单机价格从五千万美元上涨至9500万美元。以今日美元实际价值衡量,F-35单机价格预计将达到1.12亿美元。平均单机价格包括研制、采购和外场试验费。巨额的费用超支预示着美国空军“近日”将通报国会的JSF费用超过了纳恩-迈科迪法案(Nunn-McCurdy)规定的限制,这将启动JSF项目替换机型的评估。军事防务 全球军情

  美国空军、海军和海军陆战队预计将采购2443架JSF飞机。美国空军评估F-35A将在2016年形成初始作战能力(IOC),而上周还认为将在2015年形成IOC。3月3日“采办决策备忘录”决定将在2016年4月结束使用试验,F-35C计划在2016形成初始作战能力,F-35B计划在2012年形成初始作战能力。军事防务 全球军情

  导致费用增长的因素包括:2006年对F-35进行的减重设计、研制计划拖期、人力和管理费的增加、通用性降低、生产数量减少、原材料价格上涨(特别是钛)和重要分承包费用的增加。
名城 发表于 2010-3-17 08:28 | 显示全部楼层
f-35涨到一亿多,美军的采购量恐怕会缩水吧,其他国家的订货估计也会消减
waitforcv 发表于 2010-3-17 12:23 | 显示全部楼层
f-35涨到一亿多,美军的采购量恐怕会缩水吧,其他国家的订货估计也会消减
名城 发表于 2010-3-17 08:28



    然后反过来又推动价格上涨。。。
 楼主| speed 发表于 2010-4-9 13:39 | 显示全部楼层
美国防部启动新一轮F-35项目成本估算

2010-04-09

[据美国《防务新闻》2010年4月6日报道] 随着最新评估结果表明F-35单价已经升至1.15亿美元(按2002年币值计算,相当于现在的1.38亿美元),五角大楼已正式报告国会,F-35联合攻击战斗机项目已经违反了Nunn-McCurdy法案。紧接着,五角大楼便针对该项目正式启动了又一轮独立成本估算。
  根据F-35选择性采办报告(SAR),新的评估工作将考虑包括设计和飞行在内的全寿命周期费用;一旦结果出炉,国防部便会更新F-35的最低采购数目。SAR还透露,国会是在3月26日正式收到“违反Nunn-McCurdy法案”报告的。
  根据这份新发布的SAR,国防部现在希望F-35包括研发在内的单价能够控制在0.95~1.15亿美元(按2002年币值计算)之间。(中国航空发展研究中心  廖孟豪)
绿林好汉 发表于 2010-4-13 21:54 | 显示全部楼层
Nunn-McCurdy法案说的啥?
不管啥法案,F-35绝对不会取消吧?
as24 发表于 2010-5-9 21:08 | 显示全部楼层
f35快批量装备了,咱们的4代也要加快呀,不出10年周边日韩印都能装备f35了
shaolin1254 发表于 2009-4-30 18:20



不出10年,重四及中四也都批量生产。
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