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McDonnell Douglas has radically changed its approach to new product development under an internal project called Design, Manufacturing and Producibility Simulation (DMAPS). The new process has four steps: concept baseline, concept layout, assembly layout and build-to-package; each of which relies on three dimensional master solid models and a variety of advanced simulation and modeling tools. The result is a disciplined process that eliminates non-value added activity and provides all Integrated Product and Process Team (IP2T) members with the tools needed to effectively perform assigned tasks. McDonnell Douglas applied the new approach to a redesign of the T-45A Horizontal Stabilator. This project demonstrated that three dimensional master modeling can eliminate two dimensional drawings and enable physical mockups to be replaced by computergenerated virtual prototypes.

The U.S. Air Force has recognized the need for an alternative to the conventional hydraulic brake system. Hazards associated with fires and the maintenance required for a hydraulically actuated system are the principal drawbacks of hydraulic brake systems. In addition, an alternative brake system will be required to support a “More Electric” aircraft of the future. The solution to these problems was provided by the “Electrically Actuated Brake Technology (ELABRAT)” program, a three year program sponsored by the Flight Dynamics Directorate at Wright Patterson AFB. ELABRAT developed and demonstrated an Electromechanically Actuated (EMA) brake system to replace the existing hydraulically actuated piston housing and associated hydraulic control hardware.

This paper describes a Robotic Cell, constructed and integrated in the McDonnell Aircraft Robotics Lab, for the purpose of demonstrating “freehand” (unstabilized) drilling and blind fastener installation. The cell operates without the use of hard tooling for end effector stabilization. The cell incorporates a jointed arm robot, a computer controlled drill and countersink end effector, an automatic fastener installation end effector, an automatic head shaving end effector, quick change equipment, and a programmable logic controller. The drill/countersink end effector provides high quality holes and countersinks utilizing a conventional industrial robot without the aid of hard tooling. It can be programmed with multiple feeds and speeds, automatically control chip load and cage force, and has the ability to detect broken bits. The fastener installation end effector employed is capable of installing self locking threaded blind fasteners (blind bolts) of multiple sizes and grip lengths.

The testing of a titanium matrix composite (TMC) F-15 nose gear outer cylinder is discussed. Two cylinders were fabricated. An entire F-15 nose gear was assembled using the first cylinder. This test gear underwent static structural tests to three critical loading conditions and functional evaluations including load-stroke, rebound snubbing, jig drops and strut stroke cycling. The TMC cylinder successfully completed both groups of testing with no signs of structural or functional degradation.

The United States Marine Corps (USMC), the Royal Air Force (RAF) and Royal Navy of the United Kingdom have proven the operational benefits provided by fixed wing powered lift aircraft. The USMC demonstrated the powered lift fixed wing V/STOL light attack concept in the United States with the AV-8A. The Marines eventually needed additional range and payload capability due to expanded mission requirements, but could not afford a simultaneous engine and airframe development program. The AV-8B was developed, fielded, and successfully filled all stated Operational Requirements identified at that time. It is time now to plan for and expand the powered lift capabilities further to keep the AV-8B effective as part of the Marine Amphibious Task Force in the face of growing threat capabilities. The cornerstone of this improvement is the Pegasus −408 growth engine.

Heat powered ECS concepts using a Rankine or Stirling power cycle to drive a vapor compression refrigeration cycle were evaluated for future fighter aircraft. Arrangements with separated power cycle and refrigeration cycle working fluids were considered, as were arrangements combining these cycles via a common working fluid. Promising heat sources and working fluids for these concepts were identified. Haste heat sources in the propulsion system and airframe were compared with regard to heat capacity, temperature level, and collection system design complexity. A screening process, which distinguished between the requirements imposed by the power cycle and refrigeration cycle, was developed to select promising working fluids. Concepts were evaluated using various system arrangements, heat sources, and working fluids to minimize the ECS-related TOGW penalty.