Important to all Procedure designers - 1

28.10.2004

Submission:

I think this is just a tool to calculate OAS surface height at a given location X, Y. I doubt that it can calculate OCA(H). I do not think there is any need to worry for other Pans-Ops software suppliers!


Stein-Erik Sandvik
Advisor-Procedures design -AIS -AVINOR/Norway

Answer or Commentary:

(I.W.

The thin edge of the wedge, I agree. The OCH calculator is basically an Excel spread sheet but how do we know that the software calculates the Z value correctly in all cases. Who checked it and was the checking process rigorously documented? I have the suspicion that the OCH calculator was added to the CD-ROM as an after thought and that it was only checked by the programmers themselves. I hope I turn out to be wrong but the ICAO/software company liability issue is still there - everyone will get dragged into any incident.

In my opinion if this trend towards software development by ICAO is to continue it needs perspectives to insure that resulting software doesn't reflect someone's interpretation of Pans-Ops and that it's sufficiently tested/validated as safety critical software. In fact future work will require a much more rigorous beginning with the resolution of ambiguities in criteria, drawings and implementation practices.)