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The Architectural Assessment Tool - enhanced Model (AATe)

Disclaimer: This material is being kept online for historical purposes. The model, simulation or tool described is no longer maintained. It is no longer available on request, and/or may not function on current computer systems.


The Architectural Assessment Tool - enhanced (AATe).
The Architectural Assessment Tool - enhanced (AATe).

The AATe is an MS Excel based application with a relatively simple graphic user interface for a cost or operations analyst to define the design of each stage of a reusable launch system. The AATe works ideally for reusable booster definition at a conceptual level. Results are best used relatively, such as relative to Shuttle or relative to other concepts assessed with the tool. However, absolute values may be used as rough-order-of-magnitude (ROM) estimates in the cost analysis of recurring ground systems effort.


The AATe requires at least 29 inputs per element (an element is usually akin to a stage, but with some more flexibility in definition). For increased fidelity 62 inputs can be defined. Example Input Types are:

  • Degree of Sub-systems Integration
  • Number of Toxic Fluids
  • Reliability, Loss of Vehicle
  • Payload per Flight
  • Scale of the concept (length, width, etc).
  • Margin


  • Recurring Yearly Operations Costs
    • Operations Fixed Costs (yearly)
    • Operations Variable Costs (per flight)
  • Cycle Times for Landing, Turnaround, Integration and Launch processes (calendar days)
    • Fleet size required to achieve a flight rate per year
  • Non-Recurring Operations Costs
    • The AATe includes elements of a previous rough-order-of-magnitude "FACGSE" Facility and Ground Support Equipment (GSE) spreadsheet calculator. With this a user can gain insight into historical data and analogous:
      • Facility and Ground Support Equipment (GSE) Acquisition costs
      • Facility and GSE requirement (numbers of major facilities) required to achieve a flight rate per year


In using any model to contribute significantly or even partially to an important decision, users should be aware of the limitations of the model. Users should be aware that the AATe:

  • Emphasizes reusable vehicle design complexity and it's relation to operational complexity and effectiveness.
  • Captures design features that favor operational, recurring launch, "-ilities".
  • Does not address organizational design, as inputs or drivers (efficiency, process, practices, acquisition approach, supply chain management, best practices or business approaches).

Papers & Presentations: