Project Checkpoint

The Project Checkpoint is a decision point, usually internal to the project team, and is the point where the design team declares it is satisfied with the airspace concept’s suitability for implementation, or decides to re-develop the airspace concept or, in the worst case, elects to abandon the project altogether.

What could be the deciding factors?

During the validation process, it should become evident whether the proposed PBN implementation is possible and will meet both the project’s performance and safety objectives.  Therefore, this is the most likely place to make the decision as to whether to progress the effort and go ahead with implementation. Other factors that can influence the ‘Go’ decision and could prevent the implementation going forward:

1.  A change to the ATM system, needed to support the implementation, may prove impossible to realise despite careful identification of this enabler and a go-ahead being given by ATM systems engineers.
2.  Dramatic political events which have nothing to do with the Airspace design and which could never have been foreseen when the Traffic Assumptions were chosen, could nullify the entire airspace concept. This could occur, for example, if the entire design concept rested on the (traffic) assumption that 80% of the traffic would enter an Airspace from the west and unforeseen political events change the geographic distribution of traffic completely.
3.  Unforeseen change by the lead operator concerning aircraft equipment upgrades causes the collapse of the Business Case or, for example, Navigation assumptions.

An aware and fully integrated PBN Implementation team should not be caught out by last minute surprises described above.  However, the possibility of unexpected events is one of the reasons why it is necessary to fix a go/no-go date for implementation.