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AH-64D Longbow Block III (lots 1-6)

The Defense Acquisition Board decision regarding full-rate production for the Apache Block III helicopter program announced 24 October 2012 also approved re-designating the Apache Block III as the AH-64E model. The Army planned a Block III upgrade of the AH-64D, with funding starting in FY06 for Longbow Block III Improvements. Initially, the service had planned that only the 284 Block I aircraft would undergo the Block III modifications. However, with funding freed up from the cancellation of the RAH-66 Comanche, the Army intends to modify all 501 AH-64Ds to the Block III standard. Redeliveries of Block III aircraft are slated to begin in October 2007.

The Apache Block III (AB3) Modernization was an incremental integration of block modifications providing the capabilities for the Longbow Apache to transition to the Future Force (FF), to increase survivability, and reduce the logistics footprint. AB3 satisfies the updated Longbow Apache Capability Development Document (CDD) mandates for modernization. Among other items, the Block III upgrade includes an open system avionics architecture, the Joint Tactical Radio System (JTRS), fly-by-wire flight controls, a pure General Electric T700-GE-701D engine fleet [common with the UH-60], a new transmission, and composite rotor blades. Block III was to include a series of structural, propulsion, and avionics modifications to the helicopter. The fire-control radar on Longbow Block III was the same fire-control radar that Block I Comanche would have used.

Apache Block III (AB3) will provide Network-Centric capabilities to 634 Apache Longbows at a critical time as the Army transitions from the current force to the future force. AB3 capability enhancements are achieved via planned technology insertions such as: Future Force (FF) Connectivity-Seamless Global Information Grid Communications (Interim Communications Suite embedded in an Open Systems Architecture (OSA); Off-Board Sensors - Extended Range Sensing; Increased Survivability; Cognitive Decision Aiding System (CDAS) which speeds Critical Battle Tasks; Improved Aircraft Performance: Reduced Operations and Support (O&S) Cost and Logistics Footprint, and Increased Aircraft Readiness. To Complete (TC) funding procures the remaining components required to achieve fully configured AB3 aircraft. AB3 satisfies the updated Apache Capability Development Document (CDD) requirements for modernization. Other Support procures Table of Distribution and Allowances (TDA) Salaries, In-house Matrix and Contractor Support.

Longbow Apache Block III (AB3) was a combination of twenty three technologies aimed at enhancing crew effectiveness in battle while reducing operations and support costs. This technology insertion provides net centric warfare capabilities in the multi role combat helicopter of the US Army, future force. To enable battle-space dominance, the program incorporates open systems architecture; wideband network communications; extended range sensing; level IV control of unmanned aerial vehicles; extended range fire control radar; extended range missiles; and data fusion to merge off and on board sensor imagery. The AB3 interfaces with Stryker Brigade Combat Teams and Future Combat Systems with a fully compatible and rapidly reconfigurable open systems architecture mission processor design.

The US Department of Defense (DoD) completed a comprehensive, independent technical assessment and actionable execution plan to ensure that the minimum essential requirements were met to support successful entry of the AB3 into System Development and Demonstration (SDD). The Director of the Weapons System Technology Information Analysis Center (WSTIAC) participated in the overall assessment of the AB3 based on a review of documents, including the draft Integrated Product Team, Overarching Integrated Product Team, Program Support Review, and briefings and meetings with government and contractor personnel. Included in the review were drafts of the Acquisition Strategy Report, Acquisition Program Baseline, Test and Evaluation Master Plan, Systems Engineering Plan, and the Capabilities Development Document. WSTIAC evaluations verified that sound systems engineering principles are being developed and applied, thus permitting the proper tradeoffs between cost, schedule, and overall weapons system performance in preparation for DoD approval of the AB3 to enter the production and deployment phase at a Milestone C level.

The Longbow Apache Block III program entered the system development and demonstration phase in July 2006. On approval, the Defense Acquisition Board directed the Army to extend the development schedule due to an aggressive test plan that resulted in a higher development cost for the program. Also, the Longbow Apache Block III's production decision slipped from March 2009 to April 2010.

The Longbow Apache Block III program entered the system development and demonstration phase with one critical technology, an improved drive system, approaching full maturity. The Block III program planned to complete three phases of development and meet requirements through a series of technology insertions, each requiring integration, test, and qualification activities. The Army reported that at the start of development, these technology insertions were fully mature. Only the first phase of insertions would need to be installed at the factory. The others could be installed in the field. A production decision for the first phase was scheduled for 2010. Also, when it was approved for development, the Army was directed to extend the development schedule due to an aggressive test schedule, thereby increasing development cost.

According to a March 2007 report by the General Accountability Office, the Army was reporting on 15 critical technologies prior to development start of the Block III program. However, as it reached development start, the Army opted to report on only 1 technology as critical. The remainder of the 15 technologies were not considered critical.

The technology insertions were divided into two primary categories: those related directly to processor upgrades and those independent of processor upgrades. The first phase of planned insertions addressed some of the processor upgrades and all of the nonprocessor upgrades. The processor-dependent insertions involve both hardware and software upgrades and were not field retrofitable. They included level IV unmanned aerial vehicle control, improved electronics/modular open system approach, aircraft survivability equipment, interim communications suite, modernized signal processor unit, instrument meteorological conditions/instrument flight rules hardware and software, and radar electronic unit. Those insertions that were independent of the processor include the improved drive system, engine enhancements, composite main rotor blades, airframe life extension, and training device concurrency. This phase was planned to be complete in 2014. The second and third development efforts were processor upgrades that were software modifications and were field retrofitable. Phase two was scheduled for completion in 2016 and included the insertion of embedded diagnostics and a common data link. The final phase included cognitive decision aids, image fusion, aided target, detection and classification, supportability improvements, multimode laser, fire control radar, and radio frequency interferometer improvements. The final phase was planned to be completed after 2016.

According to program officials, the technical risk involved with these technologies was low even though no backup technology exists. If, for some reason, the technology was unavailable for insertion at its given time, the program would proceed with existing technology until the new technology could be incorporated. Further, cost impact for incorporating the technologies was expected to be minimal given the ability to add software changes in the field and because the helicopter would have to be returned to the production plant only once to accomplish upgrades.

The Block III program was again the subject of a GAO report in March 2008. The GAO reported that to upgrade and modernize the Apache system, a time-phased series of technical insertions was planned for development. The Apache Block III funding profile as of the report did not allow all of the required system improvements to be fielded with the first aircraft lot. The insertion plan was based on (1) program funding availability, (2) aircraft going to the factory one time for modification, and (3) a single final Block III configuration. The technology insertion approach was to leverage other development programs with mature, production ready technologies that would require integration, test, and qualification on the Apache Block III platform.

The GAO described system development as occuring in three phases. The first phase would complete integration qualification of all required hardware changes applied to Apache Block III helicopters. 2 limited development phases with follow-on improvements requiring further technical insertions would be necessary. With the exception of the common data link hardware, the follow-on development phases would consist of software improvements that although limited in scope, still required planning, test, and evaluation. These insertions would be applied in the field, and aircraft would not be required to return to the factory to achieve the later configuration upgrades. A low-rate production decision for the first phase of development was scheduled as of March 2008 for April 2010, with a full-ratedecision scheduled for April 2012. Subsequent configuration upgrades for the remaining development phases would be dependent on successful interim design reviews scheduled for fiscal years 2014 and 2016.

The assessment also noted that since the start of program development, the Vice Chief of Staff of the Army approved a program change increasing the Apache Block III production quantity from 597 to 634. Further, deliveries were restructured from 60 to 48 a year, thereby stretching the program schedule by 4 years. The costs associated with both the remanufacture of the additional 37 aircraft and the stretched delivery schedule led to an increase in total procurement costs, reported in a December 2006 Selected Acquisition Report.

The Boeing Company celebrated delivery of the first AH-64D Apache Block III multi-role attack helicopter to the U.S. Army Nov. 2, 2011 in Mesa. The Block III Apache began a new era in combat aviation by delivering advanced technologies and capabilities to benefit soldiers and battlefield commanders. Boeing was to produce 51 AH-64D Apache Block III helicopters for the Army under Low Rate Initial Production. The Army's acquisition objective stood at 690 Apache Block III aircraft. In addition, a growing number of defense forces worldwide had contracted for, or were considering, upgrading to or adding the Apache Block III to their rotorcraft fleets.

The Apache Block III incorporated 26 new technologies designed to enhance the aircraft's capabilities. The improved drive system features a new split-torque face gear transmission that increased power capability to 3,400 shaft horsepower. The new composite main rotor blade accommodated that power increase, resulting in improved aircraft performance with increased payload. Integrating the T700-GE-701D engine with the enhanced digital electronic control unit and other drive system technologies resulted in an increase in hover ceiling altitude at greater gross weight on a 95 degrees Fahrenheit day.

The Defense Acquisition Board decision regarding full-rate production for the Apache Block III helicopter program was announced 24 October 2012, by Army officials at a briefing in Washington, DC. Additionally, Apache project manager Col. Jeffrey Hager confirmed that the Apache Block III was being re-designated as an AH-64E model. According to the Apache Project Office, the Defense Acquisition Board, or DAB, granted approval for full-rate production, or FRP, in August and the Air Force communicated the model designation change in a September 2012 memo to the Army. Actions were under way to begin implementation of the E model designation for subsequent use by the military and industry.

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Page last modified: 27-08-2013 19:18:06 ZULU