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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.

Numerical simulations indicate that blast loading on aircraft structural joints can impart loading rates in excess of 10 Mlb/sec (ten million pounds per second, Reference 1). Experimental evidence, on the other hand, suggests that mechanical joint failure loads are highly loading rate dependent; for example, the failure load for a dynamically loaded tension joint can double from its static value. This paper discusses the progress and to-date findings of research on the assessment of strength failure of aircraft structural joints subjected to loading rates expected from an internal explosive detonation, and several associated experimental procedures to generate such dynamic loading. This work is conducted at MDC and at the University of Dayton Research Institute (UDRI) in support of the FAA Aircraft Hardening Program.

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.

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.

On the Thermodynamic Spectrum of Airbreathing Propulsion - Insights from 1958 are valid guidelines yet in 1988 - Paul Czysz. Staff Manager, McDonnell Douglas Fellow. McDonnell Douglas Corporation

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.

Effects which normally diminish the value of a manually flown instrument approach are examined in the light of flight test results with the Head-Up Display (HUD). It is possible to avoid shortsightedness (space myopia) and disorientation phenomena associated with poor external visibility, by choice of display position and format, allowing an efficient alternation between display and forward view. The display can also be designed to fit the man, in both static and dynamic characteristics, with benefits of rapid learning and accurate tracking. These results remove the basis for supposing man's intervention in the all-weather landing to be disastrous. On the other hand, man's participation may be necessary, because more information is connected with a safe approach than can be dealt with by an unaided machine. Synthesis of an automatic system with HUD may turn out to be the most acceptable solution to the overall problem of all-weather operation.