[Peetwo]

The Su_Spence SAGA continues...

Courtesy CM, via the UP...

When our “system of aviation safety” produces and perpetuates the least safe option

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When I learnt to fly in the mid-80s, there were some fundamental rules and priorities reinforced throughout the training. Those rules and priorities have their foundations in lessons learned from accidents and lives lost. They should be ‘taken as read’. They don’t need to be meddled with or obscured. That’s because, as with so many things in life, survival in aviation depends on being able to comprehend, focus on and mitigate the inbound 155mm howitzer round sized risks and not being distracted too much by the myriad marshmallow sized risks. (I don’t remember any ‘pledge’ during my training, though. It was more: If you don’t want to die, best to concentrate on … . But as part of my ‘learning journey’ I’ve resolved to take the ‘aviation safety pledge’ on the day that the first drone taxi with a passenger takes off from the first Vertiport in Australia.)

My apologies for the long post, but its length is a manifestation of Brandolini’s Law, otherwise known as the bull##### asymmetry: The time and resources it takes to undo bull##### is an order of magnitude greater than it took to create it.

The ‘default’ left hand circuit rule

One of the fundamentals reinforced throughout my training was the ‘default’ left hand circuit rule at what are now called ‘non-towered’ aerodromes. That rule is currently ‘enshrined’ in CASR 91.385. It’s now a bit different from when I learnt to fly, because the ‘default’ left hand rule now only applies after joining the circuit for a landing or while flying in the circuit after take off, whereas it used to apply even to turns joining the circuit. And now it’s not mandatory to fly at least 3 legs before landing.

As well as the safety benefits arising from consistency, of itself, there is a physical reason for the ‘default’ left rather than it being the result of a coin toss between right and left: Many fixed wing aircraft have two seats in the front and, in most of those aircraft, the PIC sits in the left seat. Left hand circuits give those PICs a better view of the manoeuvring area of the aerodrome. (For anyone who doesn’t understand the point: Think about what would happen if the side of the road on which we drive in Australia was changed to the right, but all our cars remained right hand drive.)

Therefore, there have to be substantial grounds – or at least there should be substantial grounds – like a safety case supported by the outcomes of a risk assessment on which to require right hand circuits, sufficient to outweigh and justify the corresponding inherent reduction in safety. Although requiring a right hand circuit on a runway will achieve consistency (assuming pilots are aware of and comply with the requirement if they’re turning in the circuit), it sacrifices the better visibility for many PICs and could entail further, new risks, depending on the specific circumstances.

That is why the decision has to be made – or at least should be made - by a person with the power to make, and therefore bearing responsibility for making, the decision to impose a requirement for right turns in a circuit.

Responsibility focusses one’s attention. And there has to be – or at least there should be – a clear record of that person’s decision and the basis of that person’s power to make it. ‘Back in my day’, there was a piece of squashed tree, signed by a human being, specifying the person’s name, citing the source of the person’s power to make the decision and stating, in black and white, what decision the person had made.

As a consequence of a protracted and ongoing tragi-comedy at Cootamundra (YCTM) – and other disconcerting circumstances that increasingly prevail in aviation - it appears to me that our “system of aviation safety” has deteriorated to the point at which decisions like turn directions in circuits are increasingly being made in a Monty Python-esque anarcho syndicalist commune where it’s not clear who actually makes the decision, when or why.

A bolt from the blue in our sleepy hollow

Welcome to YCTM, one of the many Australian aerodromes steeped in rich aviation history. Part of that was a locally-based ‘commuter’ airline running noisy piston twins.

Right hand circuits were directed for YCTM’s RWY 34 at night (HN). There’s rising terrain to both the east and west, and back then the township was concentrated almost entirely to the southwest of the aerodrome. Right hand circuits HN on RWY 34 kept the noisy twins away from above the centre of the township and the rising terrain to the west and southwest of the town at night. And everyone was happy.

Right hand circuits HN on RWY 34 YCTM was a typical example of the kind of circumstances referred to in the note on page 26 of AC 91-10 v 1.3 – the current version published by CASA as at the date of this post: “At many aerodromes, the circuit direction at night is different to the direction during the day. This is generally because of terrain, obstructions or noise abatement.” None of that is rocket surgery.

Decades after the imposition of the requirement for right hand circuits HN on RWY 34, YCTM has – like many country aerodromes – become very quiet. The ‘commuter’ airline is long gone. The amount of HN traffic can usually be counted on the fingers of one finger or no fingers at all. And now that straight-ins are legal, what little HN traffic there is rarely does a circuit. The requirement for right hand turns in the RWY 34 circuit HN is therefore of almost no practical contemporary consequence, either safety-wise or noise abatement-wise. (I should note here that my first touch and go at YCTM was in the mid-80s and I now live here and monitor the CTAF and area frequencies to the east and west.)

Then a ‘bolt out of the blue’ around a year ago: The ERSA entry for YCTM was amended to require right hand circuits on RWY 34 during daylight hours (HJ) as well as HN. All of us locals had a whisky tango foxtrot moment. Who came up with that idea, and why?

Who’s responsible?

My attempts at getting a clear answer to the questions “who” and “why” quickly bogged down. I asked those questions of CASA, who effectively pointed at the aerodrome operator, but the aerodrome operator pointed at CASA.
I made an FOI request for the instrument – surely there’d be a piece of paper – signed by a delegate of CASA’s power – surely it’s CASA’s power – recording that individual’s exercise of that power so as to require right turns in the RWY 34 circuit HJ. But that request appeared not to make sense to CASA’s FOI officer. (I’m not criticising CASA’s FOI officers. They have always been very efficient and professional in response to my FOI requests.)

I changed the request to any documents with any relevance to right hand circuits in the last couple of years. The returned documents left me none-the-wiser as to what individual made the decision or that person’s reasons for it. But the documents did reveal one astonishing circumstance: The aerodrome operator had, as a consequence of us locals pointing out the risks that had been created by the change and a REPCON I submitted to ATSB, put out a NOTAM in an attempt to effectively reverse the decision, but CASA quashed the NOTAM!

Cue the Monty Python Flying Circus theme music

For a while, us locals speculated that the change may have been purportedly justified on noise abatement grounds, but subsequent events and intel I’ve gathered reveal this Python-esque course of events that explains how stuff makes it into AIP these days:

Someone who’s apparently a CASA Aerodrome Inspector – a Mr Iain Bailey - had what I can only describe as a thought bubble. His thought bubble was that there is a material risk of pilots coming to different conclusions as to whether it is HJ or HN at the same time at the same location, and that risk – according to Mr Bailey - created a safety risk at YCTM because RWY 34 was right hand only HN. Mr Bailey had a further thought bubble as to how to mitigate the safety risk he perceived: Require right hand turns in the circuit HJ as well as HN on RWY 34.

Mr Bailey apparently put those risks and the mitigation to the aerodrome operator, whose personnel have no aeronautical experience and who therefore assumed – reasonably – that Mr Bailey’s thought bubbles were the product of competent analyses of the objective facts and operational risks, and the aerodrome operator ‘requested’ a change that was, in fact, Mr Bailey’s proposed solution to a problem perceived by Mr Bailey.

Let’s assume, for a moment, that the safety risk perceived by Mr Bailey is a material one.

The immediate questions that would have jumped to my mind would have been: First, why was that risk created and allowed to exist for decades at YCTM and the “many” other aerodromes, referred to in AC 91-10, at which “the circuit direction at night is different to the direction during the day”? Was there some recent change such as to render pilots, in the vicinity of YCTM, more likely to come to different conclusions about when daylight ends and begins and more likely not to hear or see each other while one of them has mistaken daylight for darkness or vice versa? The objective answer to the latter question is: No.

I’d therefore have to consider the possibility that all those aerodromes referred to in the note I quoted from AC 91-10 are a safety timebomb waiting to explode around the beginning or end of daylight, and that perhaps YCTM has been lucky enough to have been saved.

Therefore the next question that would have jumped to my mind would have been: What would the worst possible outcome be in the event that two pilots do, in fact, come to different conclusions as to whether it is HJ or HN at the same time and place where their chosen RWY has left hand circuits HJ and right hand circuits HN? Assuming they decide to fly a circuit rather than doing a straight-in (the latter option being available irrespective of the circuit direction and whether it’s HJ or HN), I would have thought they end up on downwind on opposite sides of the RWY. One is on a right hand downwind, believing it’s HN and the other is on a left hand downwind, believing it’s HJ. That does not strike me as being a particularly dangerous situation.

Then they turn head-head-on base, but that’s at ‘low’ speed with flaps out and at least one of them is lit up like a Christmas tree because the pilot of one of the aircraft believes it’s HN. Or they join the circuit on head-to-head base legs, but still at ‘low’ speed with flaps out and at least one of them is lit up like a Christmas tree. Yet neither pilot hears or sees the other aircraft during any of this? (At this point I’m thinking of the Ministry for Silly Walks sketch.)

The next question that would have jumped to my mind would have been: Would requiring right hand turns on RWY 34 HJ create any new risks? The objective answer to that question is: Yes. First, there’s the increased risk inherent in the change (the fundamental basis of the ‘default’ left turn rule). Secondly and more importantly, it creates the new risk of the most dangerous of scenarios: pilots choosing opposite direction runways in nil-to-little wind situations, ending up head-to-head at high speed on opposite downwinds HJ – one right hand for 34 and the other left hand for 16 - with each being a stationary speck in the other’s windscreen. (That scenario highlights another safety benefit of the default rule: If different pilots choose opposite direction runways in nil-to-little wind conditions but choose to fly a circuit and comply with the default rule, they won’t end up head-to-head at high speed on opposite direction downwinds or crosswinds.)

The final question that would have jumped to my mind would have been: What new risks would arise if the requirement for right hand turns in the circuit on RWY 34 HN was revoked and the default rule prevailed 24/7? If the answer to that question were no new risks, the mitigation of the risk of and arising from pilots coming to different conclusions as to whether it is HJ or HN becomes pretty obvious: revert to the default rule HN and HJ.

Isn’t the existence and location of any infringing obstacles relevant to the decision as to the required circuit direction?

Perhaps it was pure coincidence but, after I submitted my REPCON about the increased risks created by the change to right hand circuits HJ on RWY 34, a NOTAM was promulgated which identified and detailed all of the infringing obstacles in the vicinity of YCTM. And the closest and tallest of the identified obstacles are under or close to a right base leg for RWY 34. In contrast, no infringing obstacles were identified under or near a left base leg for RWY 34.

None of the identified infringing obstacles is marked on any aeronautical chart. And they’re not mere bushes infringing by a mere 4’, per the infamous YSSY NOTAM. The two closest obstacles infringe by 185’ and 146’ respectively and are within the circuit area.

The closest, tallest and most infringing of the obstacles is a cell tower/digital TV tower erected on a hill in the circuit area long after the ‘commuter’ airline operating out of YCTM went defunct. That tower presents only a remote risk to the rare HN traffic at YCTM, given that it and the nearby infringing radio tower are illuminated and very easy to spot at night from the air. It’s not so easy to spot them from the air during the day in some circumstances, and impossible to see if there’s an engine cowl or wing in the way. But that wasn’t much of a problem when 34 was left hand HJ.

That’s why us locals had the whiskey tango foxtrot moment when the change to right hand circuits on 34 HJ came out of the blue. But we’re not most ‘at risk’, precisely because we know about all the obstacles. The most ‘at risk’ are ‘outsiders’ who, when flying in, make the reasonable assumption that no “system of aviation safety” would deliberately concentrate circuit traffic over the only infringing obstacles in the circuit area when there were available and safer alternatives and, in any event, infringing obstacles like comms towers in the circuit area would be marked on aeronautical charts.

Are objective facts and risks affected by a popularity contest?

Another result of the REPCON was that the aerodrome operator then consulted local operators about the change. Although I’m not criticising the aerodrome operator’s personnel, as they were merely being pulled from pillar to post, the concept of consulting about these kinds of changes is surreally silly. The objective facts and risks are what they are, unaffected by a popular vote or personal opinions.

Infringing obstacles are where they are and are the height they are, and are as easy or difficult to spot as they are in different circumstances, despite any consensus or disagreement otherwise. Risks inherent in right hand circuits rather than left hand circuits are what they are. The risk of pilots coming to different conclusions as to whether it is HJ or HN at the same time at YCTM are what they are. The risks of pilots choosing opposite direction runways in nil-to-little wind situations, ending up head-to-head at high speed on opposite direction downwinds HJ are what they are. Noise is either a problem or it isn’t and, if it is, it’s either solvable by a change in circuit direction or it isn’t. (As it turned out, and unsurprisingly to me, the consensus of those consulted by the aerodrome operator– with combined aeronautical experience of centuries and tens of thousands of hours - was contrary to the thought bubbles. That’s what led to the aerodrome operator issuing the NOTAM trying to address the risks, which NOTAM was quashed by CASA.)

ERSA was then subject to the usual amendment cycle. The obstacle data from the NOTAM was incorporated into the ERSA entry for YCTM but the requirement for right hand circuits on RWY 34 HJ and HN remained. When I asked CASA what was going on, I was told CASA was waiting for “a data item” from the aerodrome operator.

Please provide a risk assessment to undo a change that was not supported by a risk assessment

The aerodrome operator then revealed to local users that CASA had asked the aerodrome operator for a risk assessment to remove the right hand circuit requirement! That was, apparently, the ‘data item’ for which CASA was waiting before it would change the circuit direction text in the YCTM ERSA. The aerodrome operator asked local users how to do the risk assessment because the aerodrome operator does not have the operational expertise to do that assessment. (And for that request the aerodrome operator is to be commended. But I note that the circumstances are a demonstration of the fact that the Part 139 and Part 175 provisions about the qualifications and competence of aerodrome operator personnel and aeronautical information originators are practically meaningless.)

Then a meeting occurred between Mr Bailey, aerodrome operator representatives and user representatives, at which the aerodrome operator made clear that right hand circuits on RWY 34 were not its idea and weren’t required for noise abatement reasons and the local user representatives made clear their safety concerns about the prevailing, new arrangements. But Mr Bailey defended those arrangements and invited a written submission to him as to why they should be changed.

Pause here to ponder the surreal silliness of the course of events.

The new requirement for right hand circuits on RWY 34 HJ was pressed on the aerodrome operator by CASA, without any risk assessment having been done and documented by CASA or the aerodrome operator. CASA then attributed the change to the aerodrome operator because the aerodrome operator had requested it, but the aerodrome operator had actually been pressed by CASA to make the request. When the risks arising from the change became evident to the aerodrome operator and the aerodrome operator tried to do something about it, CASA thwarted those attempts and is now perpetuating the new requirement on the basis that the aerodrome operator has not done and submitted a risk assessment to CASA, which risk assessment the aerodrome operator is not competent to conduct. During this ‘process’ a popularity contest was run and the new arrangements lost, but that outcome is objectively and practically irrelevant.

And Mr Bailey continues to defend the change as a good idea.

You could not make this stuff up.

My thoughts on what a competent risk assessment would have identified

I reckon that had a competent risk assessment been done, it would have identified that:

- Left hand circuits for fixed wing aircraft are generally inherently safer than right hand. (Hence the default rule and why there should be a safety case supported by a competent risk assessment to justify any departures from that rule.)
- Not only did the justification for the original HN right hand circuit requirement on RWY 34 YCTM no longer exist, infringing obstacles had subsequently been erected under or close to the right base leg for RWY 34. Changing to the default left hand circuits HN (and leaving it the default left hand HJ) would move the tiny amount of HN RWY 34 circuit traffic away from those obstacles.
- The infringing obstacles in the YCTM circuit area are not marked on any aeronautical chart.
- An aircraft maintaining a perfect 500’ above YCTM aerodrome – the circuit height expressly recommended in CASA advisory material for ‘low performance’ aircraft - would be less than 200’ above the top of the closest and tallest of the infringing obstacles. Changing to the default left hand circuits HN on RWY 34 and leaving it left hand HJ would not only move the tiny amount of HN circuit traffic away from those obstacles, it would keep HJ aircraft with ‘less than perfect’ altitude management and altimeters away from those obstacles while descending on base for 34.
- Right hand circuits on 34 HJ and left hand circuits on 16 HJ would create the new risk of the most dangerous of scenarios: pilots choosing opposite direction runways in nil-to-little wind situations, ending up head-to-head at high speed on opposite downwinds HJ, with each being a stationary speck in the other’s windscreen. Leaving RWY 34 left hand HJ would avoid creating that new risk.
- Obstacles on the ground can be difficult to spot from the air HJ, because they are sometimes obscured by ground clutter and, in any event, are impossible to see through an engine cowling or wing. Changing to the default left hand circuits HN on RWY 34 and leaving it left hand HJ would move or keep traffic descending on base for RWY 34 away from those obstacles, thus mitigating the risk of the obstacles being difficult to spot or impossible to see from the air.
- There are no infringing obstacles under or near a left base leg for RWY 34. Thus, changing to the default left hand circuits HN and leaving it left hand HJ on RWY 34 would not put aircraft descending on base nearer to any infringing obstacles.
- The probabilities of pilots coming to different conclusions as to whether it’s HJ or HN at the same time at the same aerodrome, multiplied by the probabilities of neither hearing nor seeing the other at all, results in extraordinarily remote probabilities. How many reported accidents or incidents have been caused by those differing conclusions? Unable to find one. [Every experienced pilot with whom I’ve discussed the HJ/HN different conclusions thought bubble risk considers it to be – expletives deleted - laughable. It’s a marshmallow sized risk.]
- Assuming instead that Mr Bailey is correct and the risk of and arising from pilots coming to different conclusions as to whether it’s HJ or HN at the same time at the same aerodrome is material, changing to the default left hand circuit HN and leaving it left hand HJ on RWY 34 at YCTM would mitigate that risk without creating any new ones. If the default rule applied day and night, different conclusions from different pilots about whether it is night or day at the same time at the same place would make no difference to the required turn direction in the circuit. It would either be left or … left.

(I think that a competent risk assessment would also conclude that the only YCTM runway for which a departure from the default rule may be justified is RWY 28. Requiring right hand turns in the RWY 28 circuit would move its base leg away from the infringing obstacles and move its downwind leg away from above the township over to the farm paddocks on the northern side of the aerodrome. But maybe the ‘head-to-head’ downwind risk RWY 10/28 would outweigh the benefits. Someone with expertise should turn their mind to these matters.)

I’d welcome any feedback as to any mistakes I’ve made as to facts and logic. Maybe I’ve overlooked some glaringly obvious factor that makes sensible an outcome that seems patently absurd to me. Or maybe the purported justification for the change is just a smokescreen for some other agenda but, as they say, if you have to make a choice between a conspiracy and incompetence, pick incompetence.

Where we are at: The least safe option

CASA has implemented the least safe option and CASA is the reason it remains in place. The wrong mitigation has been applied to a marshmallow sized risk, thereby unnecessarily creating a new, bigger risk.

The safer and simplest option is the default rule.

As I said in my most recent email to CASA on this subject, it’s like the maritime safety regulator knowingly mandating a shipping lane that concentrates traffic over the shallowest water in a harbour instead of an available deeper route with no disadvantages. What competent maritime safety regulator would do that? And maybe it would be a good idea to get the submerged rocks marked on the nautical charts?

Post script – maybe none of this matters?

These days I’m frequently forced to confront the possibility that none of this really matters. After the change at YCTM, plenty of traffic continued to do left hand circuits on RWY 34 HJ, the pilots evidently blissfully unaware of the change. And an increasing number of pilots take the view that they are allowed to do a turn in the circuit contrary to whatever requirement applies, simply by announcing what they’ve decided to do.

The latter phenomenon particularly fascinates me. It seems to me to be something that is deliberately trained these days and must, therefore, be contained in training documentation given the smiley face of approval by CASA or observed by CASA in its surveillance activities. But I’m yet to find the regulatory provision that authorises the practice, unless it’s in circumstances of extreme weather or other unavoidable cause. In the case of turns in the circuit, there are some exceptions ‘built into’ CASR 91.385, but I can’t find the one covering all turns that a pilot happens to announce. (I might give this a go some time: I’ll announce on the Cootamundra Matters Facebook page that I’m doing a ‘non-standard’ approach to the Woolies carpark by driving down the right hand side of main street and entering the carpark though the exit. I guess the police will be fine with that if there happens to be nobody coming the other way during my approach.)

I used to think that avoiding approach points on departure from a GAAP – sorry, ‘Metropolitan Class D’ – was a fundamental rule, but apparently departures via The Oaks were (remain?) SOP at YSCN.

When I asked CASA whether the ERSA entry for YOAS: “All CCT to W of AD”, was an instruction requiring and therefore authorising right hand turns in the RWY 18 YOAS circuit, I did not understand the answer I was given. Silence remains the stern reply to my supplementary question to CASA: “Is that a ‘yes’ or a ‘no’?” Ditto my supplementary question as to where an aerodrome operator derives any power to decide what the rules are in the air above and in the vicinity of the aerodrome. I always thought that that was CASA’s power and therefore responsibility.

Every time I pop into YCWR these days I just shrug and laugh at this chronic nonsense in ERSA: “RWS not AVBL for TKOF or LDG”. That’s the product of the incompetent leading the unqualified, but most pilots evidently don’t realise that those words technically mean that you’re not allowed to land or take off anywhere inside the 90 metre wide RWS which, by definition, includes the RWY. I therefore suppose the words don’t really matter and it’s OK to load up ERSA with whoever’s thought bubbles inflate from time to time.

VFR “departure calls” on CTAF? If this is a manifestation of being “professional” – per The Pledge – then please be really “professional” and give your departure call on the Area frequency where Centre will hear you. If it’s about safety, Centre should be able to hear your departure call, shouldn’t they, because Centre’s knowledge of your existence and intentions will add safety to your flight, won’t it?

Perhaps the relatively-recent spate of mid-airs is just the result of random chance rather than any loss of focus on fundamental rules and priorities during training and subsequent reviews. And maybe there’s been no loss of corporate competence in CASA. ATSB evidently thinks so, given the frequency with which it chooses not to investigate ‘light aircraft’ accidents. But then I can’t help asking myself: Given that the ATSB, like CASA, is part of the system of aviation safety, who has the competence and responsibility for reviewing whether ATSB’s decisions are objectively justified?

Yours in aviation safety.

You can visit the UP thread - HERE - to see the commentary/posts that followed...

MTF...P2