http://www.dsti.net/News/55268.htm
雷聲公司推遲交付155毫米GPS制導炮彈
[據美國《防務新聞》2009年7月29日報導] 美國陸軍官員透露,由於慣性測量元件(IMU)存在問題,雷聲公司已經暫時中止向陸軍交付“神劍”155毫米GPS制導炮彈。
陸軍發言人在書面中陳述:XM982“神劍”制導炮彈需要在超過15000g的高超載環境中使用,彈載IMU存在著內在的魯棒性設計缺陷,導致了大約5%的失效率。目前還不能斷定是在設計還是在加工過程中出現了問題。
發言人表示,IMU在炮射環境下加速度計發生了高偏差的變化,這意味著,加速度計不能正確測量炮彈在發射後的運動情況。
陸軍已經接收了數萬發XM982炮彈,並在2006年的伊拉克戰爭中首次使用。發言人表示,炮彈在戰場上並沒有發生故障,出現的問題是在裝運到戰場之前發現的,而且都已經扣留在了生產工廠。
雷聲公司將要為1075發炮彈更換IMU,陸軍將要為此花費1630萬美元。新的生產將在8月份重新開始。
雷聲公司發言人Jacklyn Guttman表示,經過仔細評估,一種可供選擇的慣性測量元件設計已經被證明能夠滿足系統需求,同時能增強整個系統的可靠性。目前,正在對該替代型IMU進行資格認證。 (北方科技資訊研究所 李寶鋒)
http://www.defensenews.com/story.php?i=4210961
U.S. Suspends Delivery on GPS-Guided 155mm Shells
By kris osborn
Published: 29 Jul 2009 16:20
The U.S. Army has temporarily suspended delivery of Raytheon's GPS-guided, 155mm Excalibur artillery rounds due to problems with its Inertial Measurement Unit (IMU), service officials said.
"The XM982 [Excalibur] round is required to operate in an environment that exceeds 15,000 times the force of gravity. There was an inherent lack of design robustness in the qualified IMU configuration which resulted in a failure rate of approximately five percent. We have not been able to conclusively trace the exact cause to a design or process issue," an Army spokesman said in a written statement.
The spokesman said the IMUs, which were made by Minneapolis, Minn.-based Honeywell, "experienced high bias accelerometer shifts during gun launch," meaning that the accelerometer did not correctly measure the movement of the shells after firing.
The Army, which has taken delivery of tens of thousands of XM982s, first fired the rounds in combat in 2006 in Iraq. The spokesman said the munitions have exceeded expectations.
None of the rounds in theater have had a problem, the spokesman said. "Problems were identified before shipment to theater and have been held at the production facility," the spokesmen said.
Raytheon will replace the IMUs on 1,075 shells, the spokesman said. The Army will pay $16.3 million for the replacement, he said.
New production will resume next month, the spokesman said.
Raytheon spokeswoman Jacklyn Guttman said, "After careful evaluation, an alternative Inertial Measurement Unit design has proven to meet system requirements while providing an opportunity for increased overall system reliability. The effort to qualify this alternative IMU is in progress, and is expected to be successful." Using the new supplier has corrected the problem, another company official said.