Reasons for Infringements

[FlyOnTrack]

In preparation for the new 2010 'flying season', (whenever that is), FlyOnTrack is beginning to expand the 'ATC/Pilot' reports' section with brief (dis-identified) snippets written by the pilots (or instructors) involved in infringements, the idea being to share the cause of their problems, in case reading about theirs prevents a future one.

There are four 2009 ones there to start off, (plus a previous longer report) and there will be more infringement snippets (from last year) released over the next few weeks. See http://www.flyontrack.co.uk and click on 'ATC Pilot Reports'. Feel free to discuss!

[Brian Hope]

It is interesting that two of the posted infringements were of instructors with student pilots, no doubt in club aircraft. Neither mentions using GPS, by far the best tool to quickly check your position in relation to controlled airspace if as in one case the instructor became unsure of his position, and in the other the visibility was poor and he had to modify his track to avoid an ATZ.
If instructors from bases near controlled airspace can get into trouble, it does not seem unreasonable to assume that many of the infringements in those areas are probably caused by club pilots flying without a GPS 'safety net'. Let us hope the NATS Aware GPS becomes standard issue in those areas.
Interesting too that two of the reports are for the Stansted TMZ, and both would probably (no mention is made of a height bust) have not been infringements six months ago because the aircraft would have been underneath the actual controlled airspace. In the case of North Weald (and any other field in a similar location), would it not be adviseable for ATC to advise departing pilots to either call for TMZ clearance or insure that their transponder is turned on? I would expect leaving and forgetting to get a TMZ clearance might be a regular problem.

[NATS General Aviation Lead]

Brian

You pick up on a very important point. We do not regard an incursion of the Stansted TMZ (SFC-1500ft alt) as an infringement for our statistical purposes. By default we will probably not know at the time of incident what altitude the observed contact is operating and we will therefore avoid the contact on the basis that it MAY be operating above 1500ft alt. This may be disruptive to operations inside of controlled airspace but it does provide a significant safety benefit over the situation we previously faced of 'deeming' aircraft to be below 1500ft alt and then subsequently finding the contact had infringed resulting in a loss of separation. If subsequent tracing action suggests that the contact was operating below 1500ft alt. but failed to comply with the access arrangements to the TMZ then we will offer information and advice and forward the Mandatory Occurrence Report to the CAA but we do not regard the incident as an infringement of CAS because, as you point out, clearly it is not.

We have been extremely pleased with the relatively low number of incursions of the Stansted TMZ during its first few months of operation and the access arrangements appear to be working well. Most importantly, the safety benefit derived by no longer, routinely, 'deeming' non-Mode C aircraft as being below the CTA stubs means we have not experienced any high-risk infringements in the airspace since the introduction of the TMZ.

You make a further good point about local airfields offering some protection and/or reminders of the TMZ. North Weald, Andrewsfield and Hunsdon PPR procedures all carry a reminder of access arrangements although the passing of reminders and the allocation of alternate conspicuity code (7010) by Air/Ground operators is not a concept that SRG are comfortable with. I do hope to re-visit this issue in the light of operational experience.

[FlyOnTrack]

here are four more 'pilot' reports ( Nos 5 to 8 ) - http://www.flyontrack.co.uk/content/reports.asp - latest four at the top of the list.