“Tool based” procedure design philosophy

The PHX instrument flight procedure design software package is a set of tools that can be used by a professional procedure designer to design instrument flight procedures. The PHX procedure design software is not automated software but is a “tool based” procedure design software package.

The philosophy of “tool based” software is that the instrument procedure designer is given a set of tools from which he/she can select the appropriate tool to design any type of instrument procedure. The “Tool based” procedure design philosophy relies heavily upon the fact that a qualified procedure designer is an integral part of the procedure design process. The two philosophies of procedure design software can be summed up in the following two sentences:

Automated system:
“The system shall design XXX and check for obstacles”

Tool based system:
“The procedure designer will design XXX and check for obstacles with help from the system”

A procedure design software package that is “tool based” has many advantages over an “automatic” system.

  • The control of the software is firmly in the hands of the procedure designer not the computer programmer with only second hand practical knowledge of procedure design.
  • Any types of instrument procedures can be designed not just the procedures programmed into the automatic system.
  • The procedure designer actively dictates how the instrument procedure is designed and not that the software dictates how to design the procedure.
  • It is a know fact that ICAO Pans-Ops has inconsistencies within it. With a “tool based” software package the procedure designer can make a qualified decision on how the procedure is designed and not have to leave this decision up to the software programers.
  • Efficient instrument flight procedures can be designed by taking into account the experience and knowledge of the procedure designer not the second hand knowledge of the computer programer.
  • A “tool based” procedure design software has the flexibility to design non-standard but safe procedures. This can not be accomplished with a strictly automated software.
  • A “tool based” procedure design tool does not immediately become obsolete when ICAO Pans-Ops criteria changes and can continue to be efficiently used until a new update is released.
  • In some cases there is not a specific tool for a specific task but a combination of various tools in a “tool based” software package can be used to accomplish a needed goal. An automated system does not give this level of flexibility to the procedure designer.
  • It is now an ICAO recommendation that procedure design software is validated. In a “tool based” software package this process for each new software version is faster and more reliable as only the new tools in the software need to be validated. In a fully automated procedure design software the person doing the validation must validate the entire software package for each update as some interconnected parts of the program could have changed.