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Flight safety
Letters Infringement concerns
I
found the article My Infringement in January’s magazine (p10) deeply disturbing, starting with the title. The pilot never saw more than 2,450ft on his altimeter while beneath the 2,500ft TMA. The CAA acknowledged that there was no action they needed to take and alluded to a ‘loss of separation’ being the reason for their interest. That could be caused by NATS bringing IFR traffic too close to the base of controlled airspace so that any transponder error will generate an apparent loss of separation when none actually exists. All this suggests that in Richard’s case no actual infringement ever took place. The CAA then issued a thinly veiled threat to the pilot who, having done nothing wrong, is faced with having this non-event put on his record in case he is involved in any further reports in the future. This is like the police acknowledging that you didn’t break the speed limit, but they are going to put this encounter with them on file for future use against you. Is this legal? NATS has foolishly programmed no margin into their ‘Controlled Airspace Infringement Tool’, CAIT. Transponders are inaccurate devices tested every year and will pass even when a 200ft error exists. This test is carried out on the ground and takes no account of static pressure errors in the air. In the intervening 12 months who knows how inaccurate they will become? Add altimeter error and the error caused by CAIT perhaps not using the same QNH to convert FL to altitude as that set by the pilot, and it is easy to see that the transponder readout seen by NATS can easily differ by over 300ft from the actual altitude. It is the pilot’s responsibility to fly by the altimeter, not the transponder readout, which is not displayed on many transponders. If NATS is serious about maintaining a minimum separation between IFR and VFR traffic’s transponder readouts, then it needs to move the IFR traffic higher within controlled airspace, not expect VFR pilots to fly ever closer to the ground. In the South East with obstacles on higher terrain rising up to 1,000ft or more amsl, and 1,000ft being the minimum height over congested areas, VFR traffic is already operating in a narrow band between 2,000 and the 2,500ft TMA base. We don’t need NATS trying to make that band even narrower by forcing us to fly below 2,200ft to allow for transponder errors. They need to
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stop accusing pilots of infringing unless the transponder indicates at least 300ft into the airspace to take into account the errors listed above. Our sport flying associations, the LAA, BGA, AOPA etc. should be fighting our corner and not letting the CAA and NATS intimidate pilots who never came within controlled airspace. Nothing in this letter should be read as suggesting that genuine, proven infringements are not a serious matter. Regards, Peter Kynsey.
Response from Steve Slater:
As you can imagine, the CAA is not in a position to respond directly to an individual case, but having as a matter of courtesy discussed these comments in some detail with those involved, I’m writing this in my capacity as the LAA representative to the CAA’s Airspace Infringement Working Group. This is the forum where members of all the GA associations work together with the CAA to proactively reduce the risk of infringements. Pete makes some interesting observations and is a very experienced pilot, so his comments are well worthy of note. However, I don’t agree with some of his interpretations of the processes raised in Richard’s article. I certainly welcome this letter though as it helps draw more attention to the debate. By drawing attention to infringements, it will, I hope, drive greater awareness and perhaps reduce the risk of a future similar event. I can’t agree with Pete’s use of the term ‘corner fighting’. We present our arguments, robustly at times, but all stakeholders including the LAA, BMAA and BGA, are committed to reducing airspace infringements by identifying their root causes in a ‘Just Culture’ environment. In my discussion with the Chair of the Infringement Coordination Group (ICG) which investigated the incident, he was at great pains to point out that throughout the investigation, and after the occurrence was closed, Richard was regarded as a champion of Just Culture in GA. In the CAA’s words: “Richard’s values epitomise the Culture.” In their view, Richard’s article was a perfect example of the Just Culture philosophy in sharing his experience in an open and positive manner and they’ve been highly complementary
about the way Richard has used the incident to offer his experience to others. As Peter points out, there is clearly work needed by CAA and NATS to correct the incorrect perception of the handling of infringement MORs filed by ATC units. At a more strategic level, we are continually raising the subject of lower airspace design and it is good to see that, partly based on evidence given by the LAA to the Kirkhope parliamentary enquiry in 2018, the Department for Transport is pushing the CAA and DfT hard to review their processes. I do agree with Pete that the lack of margin for variance of transponder height and altimeter height programmed into the NATS ‘Controlled Airspace Infringement Tool”, CAIT, can potentially lead to an unfair accusation of an infringement when it did not occur. However, I’ve had it made clear to me that there is no automatic assumption of anything; the CAA’s independent investigation is carried out based on MOR and pilot reports. The more evidence and information that is presented by both parties, the better. Transponder error is considered in the investigation. Where it is proven and shows that no infringement took place, then the MOR is closed with no further action. Whilst the specific details of the MOR, pilot report and investigation will not be discussed by the CAA, they have pointed out that at no time in his article does Mr Warriner claim that he did not infringe; he simply states that he did not see his altimeter showing an ’altitude greater than 2,450ft’. They accepted that a pilot in such circumstances is unlikely to focus his/ her attention solely on the altimeter when flying VFR. It was also noted that Richard has never claimed that the transponder was overreading by more than its permitted amount. One lesson to be learned here are, whatever Peter’s concerns regarding the erosion of margin, that one of the best ways to avoid the risk of infringement is to ensure a little margin for error when flying close to controlled airspace, both laterally and vertically. As Richard wrote: “Horizontal positioning has had millions of years of evolution, vertical positioning is a more recent skill”! October 2019 | LIGHT AVIATION | 9
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