『每日軍武』- P-7 (LRAACA) 遠程空中反潛戰飛機

克里斯Chris

P-7 Long Range Air ASW-Capable Aircraft (LRAACA)
P-7 (LRAACA) 遠程空中反潛戰飛機


原文：
The P-7 Long Range Air ASW-Capable Aircraft (LRAACA) was intended to replace the P-3 Orion as the primary land-based ASW patrol aircraft. The Navy selected Llockheed in October 1988 to develop this next generation maritime patrol aircraft, a virtually a new design derived from the P-3C.


In the mid-1980s, the Navy initiated efforts to replace the large number of P-3 aircraft estimated to reach the end of their useful service lives during the 1990s. Over the years, the P-3C, the Navy's latest model P-3aircraft, has lost some of its rangeand time on station capabilitiesbecause of heavier required payloads. The Navy sought a replacement plane with increased payload.


and at least the original P-3C range. The Navy also sought an aircraft with newer technology that could reduce support costs and provide enhanced antisubmarine warfare capabilities. The envisioned aircraft was a derivative of the P-3C and became known as the P-3G.


It was to include improved engines, reliability, maintain-ability, and survivability enhancements, vulnerability reductions, andadvanced mission avionics. The Navy planned to acquire 125 P-3G air-craft over a 5-year period. The Navy had been buying various versions of the P-3 from Lockheed without competition for many years, and it believed that introducing competition into further procurement would result in cost savings. The Navy sent a request for information toindustry in May 1986.


Using information obtained from the respondents,the Navy developed a P-3G specification that met its operationalrequirements. In August 1986, Office of the Secretary of Defense (om)officials approved the P-3G program. In January 1987, the Navy released a draft request for proposal (RFP) for the P-3G.


Following release of the draft RFP, no company other than Lockheed indicated an interest in building a P-3C derivative. Unwilling to award a contract to Lockheed without competition, the Navy expanded the scope of competition in March 1987 to include modified commercial aircraft as well as aircraft based on the P-3C design. In May 1987, OSD directed the Navy to conduct a patrol aircraft mission requirements determination study (payload, range, speed, survivability,etc.).


To complement this study and enhance the RFP, the Navy released a draft RFP to industry soliciting comments on the operational potential of commercial derivative aircraft to perform the patrol aircraft mission. In September 1987, the Navy released a final RFP, incorporating the findings of the OSD-directed study and the responses from industry.


Three proposals were received and evaluation began in February 1988. In October 1988, the Navy selected Lockheed as the winner of the competition. Lockheed's proposal was significantly lower in cost than proposals submitted by Boeing and McDonnell Douglas.


It was also judged to be technically superior, with a less risky technical approach. On January 4, 1989, the Defense Acquisition Board,(DAB) recommended full-scale development of the program. The next day, the Navy awarded a fixed-price incentive contract to Lockheed to design, develop, fabricate, assemble, and test two prototype aircraft, designated the P-7A.


The contract had a target cost of $600 million and a ceiling price ofabout $750 million. In March 1989, the Navy estimated acquisition of125 P-7A aircraft at about $7.9 billion (escalated dollars). Of this total, development cost was estimated at $915 million (escalated dollars).

Procurement of each production version aircraft was estimated at about $56.7 million. In November 1989, Lockheed announced a $300-million cost overrun in its development contract due primarily to schedule and design problems. In the following months, Navy and Lockheed officials held extensive but unsuccessful discussions in an attempt to address the contract issues.


By letter dated July 20, 1990, the Navy terminated the P-7A development contract for default, citing Lockheed's inability to make adequate progress toward completion of all contract phases. The bulk of funds in the amended FY1991 budget request for the P-3 modernization program were for the P-7 LRAACA aircraft program. Continuation of the P-7A contract was one option that was presented to the Defense Acquisition Board (DAB) in November 1990. Both the House and the Senate fully funded the request.


In order to avoid prejudicing the DAB decision process, the Congress decided to authorize an amount that would fully fund the fiscal year 1991 effort of any of the alternatives to be considered by the DAB. The program was finally cancelled by the DAB at the end of 1990, on the grounds that it had fallen behind schedule, which called for the two prototypes to be delivered in 1992. Some 123 production P-7As had been planned. This decision left the Navy without a program to replace its aging P-3 aircraft. The Boeing Update IV avionics upgrade, an important element of the P-7A, was was initially to have been applied to 109 earlier US Navy P-3Cs, but in 1992 this work was also cancelled. The British Nimrod MR2P was to have been replaced by the P-7A, but cancellation of that program forced the British Ministry of Defence to issue requirement SR(A)420 for a replacement maritime patrol aircraft (RMPA).

[ 本文最後由 jacklf2004 於 07-10-7 03:03 PM 編輯 ]

克里斯Chris

Specifications(數據)
	P-3C	P-7A
Max Takeoff Gross Weight	139,760 lbs	171,350 lbs
Flight Design Gross Weight (3.0g)	135,000 lbs	165,000 lbs
Maneuver Weight (3.5g)		137,000 lbs
Design Zero Fuel Weight	77,200 lbs	105,000 lbs
Maximum Payload	22,237 lbs	38,385 lbs
Fuel Capacity	62,587 lbs	66,350 lbs
Maximum Landing Weight	114,000 lbs	144,000 lbs
Design Landing Weight	103,880 lbs	125,190 lbs
Sonouoy Capacity	84	150-300
Wing Span	99.6 ft	106.6 ft
Wing Area	1300 sq ft	1438 sq ft
Fuselage Length	116.8 ft	112.7 ft
Height	34.2 ft	32.9 ft

[ 本文最後由 jacklf2004 於 07-10-7 03:04 PM 編輯 ]

克里斯Chris

武器介紹：

P-7 (LRAACA) 遠程空中反潛戰飛機






P-7是洛克希德公司在P-3C反潛機的基礎上改進研製的換代反潛機，過去曾用代號P-3G。1987年美國海軍提出P-3C的後繼機「遠程空中反潛戰飛機」(IRAACA)的招標要求。主要的設計要求有4個：一是裝載先進的航空電子設備，含150枚聲納浮標等；二是續航時間在4小時以上，航程不小於3000公里，巡航速度在0.55馬赫以上；三是以反潛為主，兼顧反艦和佈雷，可載8枚MK-46或MK-50魚雷及4枚「魚叉」反艦導彈；四是可使用P-3C的設施，能以最大重量在2438米長的跑道上起飛。

克里斯Chris

續:


該項目由波音公司的波音757改、麥道公司的MD-91改、洛克希德公司提出的P-7A三個方案競標。1988年洛克希德公司的方案入選。P-7A遂於1988年10月開始研製，原計劃於1991年9月出廠，同年12月首次試飛，井初始生產 l架原型機，6架預生產型。但由於該公司招標時考慮不周，認為新機可以大量衍用原P-3C的設計基礎，實際開工時卻發現兩者只有3％的共通性，近似於全新開發，所以經費大幅超標，於是該計劃被擱置多年。直至1997年，北約及其它西方國家要求更新反潛機的呼聲日益高漲，加上法國達索公司開始積極發展「大西洋」ATL-2型反潛機，意欲搶奪市場的姿態咄咄逼人，因而迫使洛克希德公司重新啟動並加速了P-7A的研製。

P-7A採用下單翼，翼上四發動機短艙佈局，與P-3相比，加長了機身、尾罩，去掉了磁異常信號探測器尾桿，蒙皮使用鋁合金半硬殼抗破損安全結構，採用數字式電傳操縱系統。動力裝置為機翼上的發動機艙內4台通用電氣公司的TF407渦槳發動機，單台功率3729千瓦(5000馬力)，驅動15WF型五葉複合材料螺旋槳。發動機採用全數字調節和紅外信號抑制排氣口，機內燃油37703升，裝有 GPCT133-7輔助動力裝置用以驅動控制系統和150千瓦發電機。

克里斯Chris

續：

座艙內共有9名乘員，兩人駕駛艙內裝有6個彩色顯示器和平顯，機身中段為戰術協調員與4名設備操作員工作室。前面為計算機艙和兩個休息床，機翼以後為投放式聲納發射艙，後艙內有兩個目視觀察員及增加兩個作戰控制台，最後面是乘員休息艙。

現代核動力潛艇的水下續航力驚人，為了對其進行連續監視，北約及其它西方國家的反潛機必須頻繁交替換班，以完成偵測、標定、鑒別和跟蹤的任務。所以彼此之間的信息轉換經常發生，如果反潛設備規格不統一，必然造成兼容性問題，影響作戰效率的發揮。基於這種情況，新一代P-7反潛機的綜合反潛系統將由美、英、德等三國共同開發，力求全面協調。該機預計2001年前將可全部交付使用。

克里斯Chris

武器數據：

動力裝置  
  動力裝置為機翼上的發動機艙內4台通用電氣公司的TF407渦槳發動機，單台功率3729千瓦(5000馬力)，驅動15WF型五葉複合材料螺旋槳。

  主要機載設備
  主要機載設備以「更新IV」型綜合反潛設備為基礎，其中包括：能探測低噪音潛艇的聲納系統、戰術電子支援系統、AN/APS-137(V)3型合成孔徑雷達、數字式磁異信號探測器、AN/AAR47型導彈告警器、先進威脅告警與干擾發射裝置、LTN-72型慣性導航系統、微波著陸系統、飛行管理系統、激光陀螺和GPS。


  武器裝備
  在機身內有長4.7米的武器艙，機翼下有12個外掛架。在武器艙與外接架上能攜帶的反潛武器包括：深水炸彈、水雷、Mk-46魚雷、Mk-45魚雷、照明彈、「魚叉」反艦導彈、「小牛」空對地導彈、箔條彈紅外干擾彈撤布系統。


  尺寸數據  
  機長34.37米，翼展32.49米，機高10米  

  重量
  空重33520千克，正常起飛重量74843千克，載重17411千克，零燃油重量47727千克，最大載油量30096千克。


  性能數據
  最大巡航高度：10668米
作戰半徑：3500千米(巡邏4小時)
巡邏時間：5小時50分鐘(離基地2960千米)。