Leaddie
Ostensibly small words can often have substantially big differences in reality. The word “final” in the next sentence is an example:
I am firmly of the view that the navigation tolerances quoted do NOT constitute a direction as to the final track of an aircraft flying in G, in an area close to a CTA boundary.
I am firmly of that view, too.
So what? Infringing the buffer isn’t the offence.
The direction requires a tolerance to be applied to the “intended” flight path.
In order to comply with the direction, people must first know the direction exists and what it means.
It means, for example, that if someone intends to go from A to B, VFR by day, at an altitude that will result in the aircraft being at around 4,000’ AGL, the person must check that no point on the line A to B is closer than 2NM from the boundary of controlled or restricted airspace. If the line is at any point closer than 2NM to the boundary, the intended flight path must be changed from, for example, A to C or B to D.
When someone flies a perfect track 0.5NM parallel to the boundary of controlled airspace, the very strong inference is that the person:
- doesn’t know about or hasn’t complied with the direction to apply the required tolerance to the intended flight path; and
- isn’t navigating by visual reference to the ground or water.
In contrast, when someone plans to fly a leg A to B that is 2NM parallel to a boundary, takes off, gets to the leg A to B, gets a visual fix on A, takes up the planned heading to get to B, drifts to a point 1NM from the boundary, takes a visual fix and alters heading to restore the intended track (and therefore required tolerance), the very strong inference is that the person:
- does know about and has complied with the direction to apply the required tolerance to the intended flight path; and
- is navigating by visual reference to the ground or water.
If you want to implicitly assure people that they’ll always be OK provided they’re always just outside controlled or restricted airspace, that’s your risk. But I’d also be urging them to be prepared to:
- show an FOI a flight plan with the intended flight paths that comply with the required tolerances; and
- have a credible explanation as to why the actual tracks were so different.