The "TTR" reference is to "Toronto Terminals Railway".
Please take a look at this Wikipedia article for more details: https://en.wikipedia.org/wiki/...
The program tools are organized into 15 separate categories, which range in scope from aeronautics and propulsion, to system testing and handling, according to the catalog.
For example, the Vehicle Sketch Pad, or OpenVSP, is a tool NASA uses to design aircrafts by way of geometry modeling.
so go have a look and see what kind of use you can get from these tools
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I have yet to see any problem, however complicated, which, when you looked at it in the right way, did not become still more complicated. -- Poul Anderson