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Advanced Attack Helicopter (AAH) (1970-1981)

In August 1972 the Army canceled the Cheyenne helicopter program and started to develop an Advanced Attack Helicopter (AAH), a twin engine, single rotor helicopter designed specifically for use against tanks. Cost and performance characteristics were defined, and, with the approval of the Deputy Secretary of Defense, the Army on 15 November 1972 invited industry to submit proposals for production prototypes. Bell and Hughes helicopter companies were selected to produce the prototypes. The Advanced Attack Helicopter program was won by the Hughes (model 77) YAH-64 in competition with the Bell YAH-63 (1976).

The Army stated that the AAH would be superior to the current attack helicopters in its ability to hover out of ground effect, and operate day or night in adverse weather. The AAH would also have a higher degree of agility, heavier fire support capability, and better survivability than current attack helicopters. The AAH was also intended to have better maintainability than current helicopters. Army force structure plans envisioned a mixed attack helicopter fleet of AH-1 Cobras and AAH's. Fixed-wing fighters would complement the attack helicopters in accomplishing the overall close air support mission.

The Advanced Attack Helicopter was to be a twin engine, rotary wing aircraft designed as a manned aerial weapons system. The Army envisioned it would be capable of defeating a wide range of targets and of performing its mission at night and under adverse weather conditions. The AAH would also be an integral element of ground units and contribute mobile and effective firepower to the anti-armor capability of the Army in the field. Alrcraft armament would include the TOW anti-tank missile system, a 30 millimeter automatic cannon, and 2.75 inch rockets.

In January 1972, a special Army Task Force was established to make an in-depth study of the operational requirements for an attack helicopter in the 1975 to 1985 timeframe. The study was based on analytical Investigatlon, supplemented by engineering flight tests of Sikorsky's Blackhawk, Lockheed's Cheyenne, and Bell's King Cobra Attack hehconter prototypes; field experiments; and Southeast Asia combat experience. As a result of the Task Force report issued in August 1972, the Army approved the initlatlon of a new development program for an AAH.

In November 1972, the Army approved a new Materiel Need document for an attack hellcopter system which would provide greater agility, hover performance and heavier aerial fire support capablllty than currently possessed by existing Army weapons systems. The Army considered the AAH as its primary attack helicopter and a key factor in future military operations. The AAH was structured as a competitive prototype phase of engineering development. Two airframe contractors are competing during this phase and each fabricated two flying prototypes and one ground test vehicle. Three additional flying prototypes would be constructed by the winning contractor during full-scale development.

The Cost Estimate for AAH Program Acquisition Cost in the Selected Acquisition Report (SAP) of September 30, 1973, (which was the first SAR for the AAH Program) was $1,811.4 mlllion. This includes an increase of $11.2 million over the Planning Estimate of $1,800.2 milllon reflected in the MH Development Concept Paper, approved May 17, 1973, by the Deputy Secretary of Defense. The Army planned to purchase 9 development, which includes two ground test vehicles, and 472 procurement hellcopters at a program unit cost of $3.8 million. This Current Estimate included all identified acquisition costs of the program. However, the Army had not yet estimated the logistic support/additional procurement costs for the AAH, which were applicable for the SAR.

The Deputy Secretary of Defense specified a $1.6 mllllon (in 1972 constant dollars) design-to-cost goal for the AAH unit recurring flyaway cost based upon a procurement of 472 aircraft produced at an average rate of 8 per month. This meant that the Army and its contractors were to design a hellcopter which would cost, on the average, no more than $1.6 million each to fabricate . When research and development, spares, support equipment, and other acquisition costs were added to this cost goal, it translated to a program unit cost of $3.8 million m FY 1973 escalated dollars.

On November 10, 1972, the Deputy Secretary of Defense authorized release of the AAH Request for Proposal. The request, as issued to industry on November 15, 1972, specified a development program, including Government competltlve testing and a $1.4 to $1.6 mllllon (constant Fiscal Year 1972 dollars) design-to-cost constraint on production unit recurring flyaway cost. The Government stated it intended to award two engineering development contracts in order to achieve the maximum technical and cost benefits from competition. Each offeror was required to design, develop, fabricate and test two AAH prototypes and one ground test vehicle.

The Government did, however, reserve the right to award a single contract for five prototypes and one ground test vehicle. On February 15, 1973, five contractors responded with proposals. An Army Source Selection Evaluation Board reviewed the proposals and negotiated contracts with each offeror. Board findings were submitted In June 1973 through the Source Selection Advisory Council to the Secretary of the Army for the selection decision. Airframe development contracts were awarded to Bell Helicopter Company (Bell) and Hughes Helicopters (Hughes) in association with Hughes Aircraft Company on June 22, 1973, for the competitive phase of engineering development.

The General Electric Company provided the engines for the competitive flight test program under a July 23, 1973, modification to the company's Utility Tactxal Transport Aircraft System engine contract with the Army.

Two flying prototypes and one ground test vehicle per contractor were fabricated during the competitive development phase. 'Three additional flying prototypes were to be constructed by the winning contractor durxng fullscale development.

On March 6, 1972, the Army signed a contract with the General Electric Company for the design, development, qualiflcatlon and support of the T-700-GE-700 gas turbine engine for the Utility Tactical Transport Aircraft System. The contract was modified on July 23, 1973, to provide engine support for the AAH competitive flight test program. General Electric was to deliver four ground test and 32 flight test engines for the AAH program. The $20.3 milkon target price for the AAH engines did not include any design, development, or qualiflcatlon costs. However, any additional qualification testing or hardware fabrication efforts unique to the AAH was incorporated into the General Electric contract by supplemental agreement.

On November 29, 1973, the General Electric contract was modified to include a production design-to-cost obJective of $78,700 (average recurring price in FY 1972 constant dollars) based on 4,700 production engines, including both AAH and Utlllty Tactical Transport Aircraft System engines. The design-to-cost objective was based primarily upon total buy, schedule, and performance parameters. Variance of one or all of the parameters could impact on the design-to-cost objective. An incentive fee toward the accomplishment of that objective was establlshed within the contract's existing maximum and minimum fee limitations. No change was made to total contract target fee or cost.

For the first 30 days of the contracts, the contractors were limited to clarifying their efforts toward achieving the program's design-to-cost goal of $1.6 million unit recurring flyaway cost. For this 30-day effort, the Deputy Secretary of Defense directed that Government obligations to the airframe contractors would not exceed $1 million each. No increase in target cost or fee was authorized for the effort. Practical design trade-offs were to be identified which would reduce unit production cost, wlthout degrading the minimum performance characteristics in the contract. Initial trade-offs were accomplished and incorporated into the alrframe contracts by modification. Both contractors were given authority on July 20, 1973, to continue with their engineering development programs.

The Army requested OSD to approve a new schedule which would change the initial production contract award date from April 1978 to January 1979. This revised schedule also contained a new Initial Operational Capability date which is five months later than the date shown in the September 30, 1973 SAIL The first production dellvery date was not expected to be changed from April 1980. The need to reschedule the contract award date was primarily caused by an extentlon of the second phase of engineering development by approximately six months as agreed during contract negotletions. The operational capability date was changed to comply with a new standard Army definition of achievement of Initial Operational Capability. This change was caused only by the new definition and not by a change to the program. As of March 11, 1974, the revision had not been approved by OSD.

The tests on the first General Electric T700 engine for the Utility Tactical Transport Aircraft system began February 27, 1973, five days ahead of the schedule milestone date for First-Engine-to-Test. The design specification for the General Electric T700 production engine was 1,536 horsepower. As of December 31, 1973, General Electric's engine testing had attained 1,600 shaft horsepower. The initial flight test engine for the AAH was scheduled for delivery in November 1974.

The airframe contractors' prototype hellcopters were tested and evaluated by the Army during the competitive flyoff, scheduled to be conducted from December 1975 through March 1976. Each of the flying competitive prototypes were instrumented and had basic weapon fixing systems installed and functional. Target acquisition, tracking equipment, and fire control systems were not installed. The flight tests during competitive development wwere to determine basic airframe and engine performance, and establish safe operating conditions for future testing. Flight testing during full-scale development were to expand the vehicles' performance limits and test all integrated subsystems, Each of the three flying prototypes to be fabricated during this phase of development had all systems installed and operable.

Both airframe contractors and the engine contractor were required to establish, maintain and use Cost/Schedule Control Systems, in accordance with DOD Instruction 7000.2, Performance Measurement for Selected Acquisitions.

General Electric's system was reviewed and formally accepted on August 15, 1973. Neither Bell's nor Hughes' system had been approved for the AAH program as of December 31, 1973. An Army official said that the Army withheld validation of Bell's system until a minor problem regarding charging of overhead 1s resolved. Hughes' validation was dependent upon the contractor's correction of current discrepancies. The Army assisted Hughes so that their system can be validated as quickly as possible. Both Bell's and Hughes' systems were forecast for validation before the end of June 1974.

General Electric submitted monthly Cost Performance Reports on its projected program in accordance with contract requirements. The contractor's September 1973 report showed that the AAH engine program was 4.6 percent schedule and 57.2 percent under cost. According to General Electric, the variances were primarily caused by lower than anticipated airframe manufacturer support requirements and delays in shifting emphasis to the AAH program.

Both airframe contractors submitted monthly Cost Performance Reports on their internal cost and schedule projectlons. However, Hughes' September 1973 report showed only actual cost of work performed. No budgeted cost figures were reported. Since Hughes' and Bell's Cost Schedule Control Systems were not validated, precise measurement of performance could not be initially be accomplished. By early-1974, both contractors were slightly behind schedule and over cost. In large part, this can be attributed to the unprogrammed 30-day cost validation effort prior to full go-ahead for the contracts. This additional effort beyond the original statements of work delayed the scheduled start of design work and resulted in additional costs.

Army testing of the Advanced Attack Helicopter (AAH) provided an example of the type of activities that occur during development testing/ technical testing. The early DT&E of the AAH was conducted by the Army Engineering Flight Activity (EFA). The test was conducted in conjunction with an Early Operational Assessment (EOA), and candidate designs were flown more than 90 hours to evaluate flight handling qualities and aircraft performance. This test also included the firing of the 30 millimeter cannon and the 2.75-inch rockets. Reliability, Availability, and Maintainability (RAM) data were obtained throughout the test program; and these data, along with RAM data provided from early contractor testing, became a part of the system's RAM database. After evaluating the results, the Army selected a contractor to proceed with the next development phase of the AAH.

During the contractor competitive testing of the Army AAH, prime contractor and subcontractor testing included design support tests, testing of individual components, establishing fatigue limits, and bench testing of dynamic components to demonstrate sufficient structural integrity to conduct the Army competitive flight test program. Complete dynamic system testing was conducted utilizing ground test vehicles. Besides supporting the contractor's development effort, these tests provided information for the Army technical review process as the systems, Preliminary Design Reviews (PDRs), and Critical Design Reviews (CDRs) were conducted.

Following successful completion of the ground test vehicle qualification testing, first flights were conducted on the two types of competing helicopters. Each aircraft was being flown 300 hours before delivery of two of each competing aircraft to the Army. The contractor flight testing was oriented toward flight-envelope development, demonstration of structural integrity, and evaluation and verification of aircraft flight handling qualities. Some weapons system testing was conducted during this phase. Government testers used much of the contractor's testing data to develop the test data matrices as part of the government's DT and OT planning efforts. The use of contractor test data reduced the testing required by the government and added validity to the systems already tested and data received from other sources.

The advanced attack helicopter (AAH) remained one of the Army's high-priority items in 1976. Contractors completed developmental flight tests on the AAH airframe, and four prototype aircraft were delivered to the Army in May 1976. Competitive testing was completed in September and selection of a winner was expected in December 1976.

In February 1976, the Defense System Acquisition Review Council approved the full-scale development of the Hellfire modular missile system as the primary antitank weapon on the advanced attack helicopter. This decision followed cost and operational effectiveness analyses that indicated an advanced attack helicopter armed with the Hellfire missile would be more effective than one armed with the TOW. On 30 March 1976 the Deputy Secretary of Defense authorized the full-scale engineering development of the laser HELLFIRE. It was also decided to arm the Advanced Attack Helicopter (AAH) with the HELLFIRE. Following the review council decision for the Hellfire missile development, a request for proposals was released. Proposals from Hughes Aircraft Company and Rockwell International were under evaluation.

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Page last modified: 15-02-2014 17:32:53 ZULU