Technology – Page 3 – John Vincent

The Human Touch

One of the most irritating aspects of bureaucracy is codification. What I mean is the need to tick a box that describes you or your problem. Restaurants, retailers, charities, religions, politicians and government departments all do the same. Sophisticated or crude administrative systems fall back on the same methods.

It’s immensely unsatisfying. Applicable to me, at this stage in life, is the age tick box. It doesn’t matter where the questionnaire or data gathering exercise comes from there’s always this box that starts at 65 years old. The previous box finishes at 64 years old.

This fits the respondent into the next step-up in age. Following from this simple date is a whole plethora of assumptions about the nature of a persons’ likes and dislikes, needs and wishes. An unsympathetic algorithm can then crunch numbers and send adverts for sheltered retirement homes, medication and certain types of undemanding travel opportunities.

Now, I could join the chorus of cries against bureaucracy. That would be popular but dumb. It’s a bit like the textiles we put on daily. We could go around naked as the day we were born. Trouble is that our present society doesn’t work well in the case where everyone is naked. Cold too.

So, it is with bureaucracy. It’s not going away anytime soon. The best we can do is to hunt for better ways of collecting data and making it useful for decision-makers and those who want to sell us something. Or even political parties that are keen to target us with their messages.

In the News this week is as good a sketch for an updated Yes Minister as any. Revolution is afoot. Suddenly the pen pushers who tie you up in red tape are going to be replaced with super-efficient algorithms and artificial intelligence to return us to paradise.

I think that’s the only reason Adam and Eve had to leave the garden of Eden. Nothing to do with apples. Well, not the ones that hang on trees. It was an iPad that had fallen though a time warp. Filling in a questionnaire on happiness it seems that one of them ticked the wrong box.

I see a difficulty with replacing civil servants with robotic algorithms and artificial intelligence. It might be the case that for routine activities, where the pattern of human behaviour is straightforward and well understood, a set of operations can be undertaken with a high degree of confidence that a good outcome will be provided.

Where I see the difficulty is that humans are notoriously messy. Inclined to irritation and not the least bit logical in their personal lives. Nothing that has been said this week is about truly eliminating bureaucracy, although that’s the illusion. It’s more about mechanising it using whizzy technology that’s so much better that that which has gone before (so they say).

Let’s just grow-up. We need public administration. We need it to work well. Fundamentally, it takes people to make it work. People who are motivated to work for the public good. People who are adaptive, caring and enabled to do a good job. Give them the tools to do the job. But are we kidding ourselves if we think complex algorithms and artificial intelligence are our saviours?

The Evolution of Air Traffic Control

Until civil air traffic started to grow the need for its control wasn’t the number one consideration. The pilot was the master of the skies. A basic “see and avoid” approach was taken. See another aircraft and avoid it at all costs. Note, I am talking about the early 1920s.

If you want a nice exploration of how it all started keep an eye on the site of the Croydon Airport Visitor Centre[1]. The first London airport was not Heathrow or Gatwick. No, there’s a stretch of grass, a hotel, industrial units and out of town shopping standing on the site in Croydon of the first London airport.

Firstly, we can thank Marconi for the first radiotelephony. Providing a means for pilots to speak to airports enabled the development of Air Traffic Control (ATC)[2]. It got going out of necessity because there was limited space on the ground and many aircraft wanted to take-off and land.

Aerial navigation took off in the 1920s. A hundred years ago. WWII drove advancement in every aspect of technology. After WWII, the basic having been established, an international body was established to set standards for international flying. That’s where today’s ICAO originated.

Radar and VHF radio transmissions were the cutting-edge technology that enabled air traffic to grow. Radio navigation aids developed as did automatic landing systems. So, by the time the jet-age started there was a whole selection of technology available to manage air traffic. Not only that but the standards required for these systems to interoperate around the globe were put down on paper.

That legacy has served aviation remarkably well. Incremental changes have been made as new capabilities have been developed. Most notable of that evolution is to return elements of control to the cockpit. A traffic alert and collision avoidance system (TCAS) does just that. It provides a safety net.

What we have available to manage dense airspace and busy airports is a complex, highly interconnected, interdependent set of systems of systems and procedures that is not easy to unravel. Each part, in each phase of flight, plays its role in assuring safe operations.

News and rumours are that quick fixes are being demanded in the US. Responding to recent accidents and a perception that all the above in antiquated, a well know tech guru has been thrown at the “problem”. I shouldn’t be a cynic, as having a fresh pair of eyes looking at the next steps in the development of air traffic management should be good – shouldn’t it?

It’s my observation, as an engineer who knows a thing or two about these things, is that any simple solution means that the parties have not thought long enough about the problem. In this case there are no quick fixes. However, there’s likely to be incremental improvements and they will not come cheap.

[1] https://www.historiccroydonairport.org.uk/opening-hours/

[2] https://www.historiccroydonairport.org.uk/interesting-topics/air-traffic-control/

Future of Single Pilot Operations in Aviation

Flying embraces automation. Now, there’s a statement that didn’t ought to be controversial, but it can be. Even before we became engulfed by the modern digital age, analogue autopilots could assist in the task of flying. Some early ones were mechanical.

The need for full-time hands-on piloting of the physical controls that linked a human and an aircraft’s control surfaces is not fundamental. Large transport aircraft have stepped further, somewhat mimicking what their military counterparts did, and fly-by-wire systems have become commonplace.

As far as technological evolution is concerned, we remain in a transitionary phase. Commercial aircraft that fly overhead are a mixed community. Some, like the Boeing 737 series continue to have cables and pulleys that link aircraft systems and controls. Others, like the Airbus A320 series are the fly-by-wire digital aircraft types in regular service.

Between the pilots in the cockpit and the motion of an aircraft there is a computer. In fact, several computers arranged in a manner so that they continue to work even when subject to failures. A great deal of thought and effort has gone into designing aircraft systems that will be reliable in-service.

Looking at the safety numbers, starting in the 1980s when fly-by-wire was introduced, the overall service experience is extremely good. The practice of system safety assessment has delivered dependable and robust aircraft. Rigorous certification processes are applied.

Through the technical developments that marched on from the 1980s one requirement has remained. That is that two pilots are needed in the aircraft cockpit. Granted there are exceptions to this rule for smaller transport aircraft. Single pilot operations are not new. For example, in many countries, the Cessna Caravan[1] is approved for a single pilot.

It’s 2025. It’s difficult not to notice the debate around Single Pilot Operations (SPO). That is to open large transport aircraft operations to a new rule. Lower operating costs may be achievable by making a change. It’s even said that this move is a way of continuing aviation’s growth as it becomes more and more difficult worldwide to increase the number of qualified pilots.

It’s good to see this subject being taken up in a forthcoming conference.

RAeS Flight Operations Conference 2025: Single Pilot Operations – Logical Progression or a Step Too Far?[2] 19 March 2025 – 20 March 2025. Royal Aeronautical Society Headquarters in London.

SPO may be enabled by use of complex systems to help make mission-critical decisions. The next step maybe with real-time “artificial” copilots and intelligent monitoring. Will this move the aviation industry toward safer and more efficient aircraft operations? That is the question.

[1] https://cessna.txtav.com/en/turboprop/caravan

[2] https://www.aerosociety.com/events-calendar/raes-flight-operations-conference-2025-single-pilot-operations-logical-progression-or-a-step-too-far

Advancements in Flight Recorder Technology and Regulations

My last posting addressed accident flight recorders and airworthiness requirements. That’s not enough. It’s important to note that aircraft equipage standards are addressed in operational rules. So, the airworthiness requirements define what an acceptable installation looks like but as to whether an operator needs to have specific equipage or not, that’s down to the operational rules in each country.

Internationally, the standards and recommended practices of ICAO Annex 6 are applicable. These cover the operation of aircraft. Flight recorders are addressed in para 6.3.1. and Appendix 8. Let’s note that ICAO is not a regulator. There are international standards but operational rules in each country apply to each country’s aircraft.

One of the major advances in accident flight recorders technology is the capability to record more data than was formerly practical. This has led to standards for Cockpit Voice Recorders (CVRs) advancing from 2-hour recording duration to 25-hours.

Proposed rule changes have been hampered by the impact of the global pandemic. Some new operational rules apply only to newly built aircraft. That means some existing aircraft can retain their 2-hour CVRs.

Another technology advance is what’s known as Recorder Independent Power Supply (RIPS). RIPS can provided power to the CVR for at least 10 minutes after aircraft electrical power is lost. The RIPS is often offered as a relatively straightforward aircraft modification.

I do not know if the South Korea Boeing 737-800 was required to have accident recorders with the capabilities listed above. If they were not, then there’s a good basis for recommending that changes be made to existing aircraft.

SONAR in Ocean Wreckage Recovery

Finding aircraft wreckage in the deep ocean is possible. However, it requires a degree of good fortune. Most of all, it requires the searcher to look in the right places. Lots of other factors come into play, particularly if the ocean floor is uneven or mountainous.

The primary tool for imaging the ocean floor is SONAR. That’s using the propagation of sound in water. SONAR can be of two types. One is called “passive” and the other called “active”.

The first case is like using a microphone to listen to what’s going on around. Of course, the device used is named appropriately: a hydrophone. It’s a device tuned to work in water and not air. Afterall, sound travels much faster in a liquid than it does in air.

Passive SONAR depends on the object of interest making a noise. Just like we have directional microphones so we can have directional hydrophones.

Passive SONAR is only useful if the aircraft wreckage is making a noise. Since in the case of Flight MH370, the battery powered underwater location beacons attached to the accident flight recorders have long since stopped working this kind of SONAR isn’t going to be much use.

Active SONAR is analogous to RADAR. That is where a pulse of high frequency sound is sent out through a body of water. Then sensitive hydrophones pick up a reflection of that pulse. It is detected and all sorts of miraculous digital signal processing is done with the acoustic signal, and an image is then formed. From that displayed image the human eye or sophisticated algorithms can make sense of what they are looking at on the sea floor.

Active SONAR can give both range and bearing (direction). Timing the sound pluses from their transmission to reception can give a way of calculating range. Or distance from the object providing a reflection. Bats know how to do this as they navigate the dark.

In sea water, there are complications. Sound does not always travel in a straight line in sea water. The speed of sound in water depends on salinity, temperature and pressure. All three of these factors can be measured and compensated for in the SONAR signal processing that I mentioned above. Helpfully at ocean depths beyond a kilometre the calculations become easier.

The average depth of the Indian Ocean is over 3 kilometres. It’s mountainous underwater too. So, what are the chances of finding flight MH370 on the ocean floor after 10-years[1]? This prospect goes back to my earlier comment. It requires the searcher to look in the right places.

Just imagine encountering the Grand Canyon for the first time. It’s nighttime. An important object is lost in the canyon. You only have the vaguest theories as to where the object has come to rest. With a handheld touch you go out to search. What are the chances of finding the object?

There are several factors that are in your favour. One, you know what the object might look like or, at least, in part. Two, the easy search locations (flat/smooth) may be covered relatively quickly. Three, certain areas of the rocky canyon have already been searched. Still the odds are against finding the lost object without a high degree of good fortune.

I wish the new planned searchers much good future[2].

NOTE 1: one of my student apprentice projects was to design and build a Sing-Around Velocimeter for use in relatively shallow sea water[3]. It worked but was cumbersome in comparison with the simple throw away devices used for temperature depth profiling.

NOTE 2: To get down to the ocean depths required it’s a side-scan sonar that may be used. This active sonar system consists of a towed transducer array that can be set to work at different depths. Imaging objects on the seafloor and underwater terrain is done as a towed array moves slowly forward through the water. The scanning part is the acoustic beam sweeps left and right. Each scan builds up part of an image.

In operation, as the frequency of the sound in water goes up so does the resolution of a potential image but, at the same time, the range of the sonar system goes down. Thus, a sonar system used for surveying may have low and high frequency settings. Unlike sound in air, here high frequency means above 500kHz.

NOTE 3: What will an aircraft accident recorder look like after a decade in the deep ocean? It might have survived well given the nature of the dark cold pressured environment. This picture is of an accident recorder recovered from relatively shallow sea water (Swiss Air Flight 111).

POST: Nice view of what SONAR can do, at least in shallow water Bristol Beaufort wreckage found

[1] https://www.cbsnews.com/news/mh370-plane-malaysia-new-search/

[2] https://www.bbc.co.uk/news/articles/cewxnwe5d11o

[3] https://apps.dtic.mil/sti/tr/pdf/AD0805095.pdf

What If Semiconductors Didn’t Exist?

There are moments when it’s dark and grey outside. Moments to ponder a what-if. That’s a what-if something hadn’t happened or physical laws aren’t what they have been found to be.

In my youth I do remember making a “crystal” radio receiver[1]. A relatively fragile germanium diode and a couple of other components scraped from junk radios, record players and TV sets. It worked quite well. It was a good introduction to the theory of amplitude modulation (AM). The diode detector demodulates the radio signal and provides a faint signal to listen to. The whole arrangement is crude but cheap and simple. It depends on that useful device – a semiconductor diode.

My what-if is right there in plain sight. Let’s put aside the physical laws that give certain materials their properties. What-if the whole world of semiconductors didn’t exist?

The most immediate repercussion is that this keyboard, screen and computer would look entirely different, if it existed at all. What I’m doing now is dependent upon millions of semiconductors all doing exactly what they’ve been designed to do. Easy to take for granted – isn’t it. Our modern world is enabled by semiconductors.

Electronics would still exist. Before semiconductors were understood thermionic valves provided the ways and means to control electrical signals. Don’t think that valves[2] have disappeared in the 21^st century. There’re enthusiasts who prefer them for amplification. The sound is better (different) – so they say.

Unlike semiconductors, thermionic valves don’t lend themselves to miniaturisation. A world without semiconductors would be populated by machines that are considerably larger and heavier than those of today. But it wouldn’t be a world without sophistication. Just look at the English Electric Canberra[3]. An incredibly capable aircraft for its day. It lived a long life. Without a semiconductor in sight.

It’s difficult to imagine e-mail without semiconductors. It’s difficult to imagine the INTERNET or the mobile phone. Not that such key markets wouldn’t be satisfied by some other means. The transition to a global dependency on digital systems would probably have been considerably slowed. Maybe the pace of life wouldn’t have accelerated so much.

I don’t think we would have been trapped in a 1950s like society. Only that patterns of work would have taken a different developmental path. Would it have been the one painted in the grim tale of 1984? No. Even that takes a position of a freezing of the state of human progress.

A non-semiconductor existence would have meant less proliferation of electronic devices. It might have led to a less wasteful society where repairing equipment was given more weight.

I suspect that large global corporations would inevitably have a hold over whatever technology was most popular. That side of human behaviour is technology agnostic.

[1] https://www.nutsvolts.com/magazine/article/remembering-the-crystal-radio

[2] https://brimaruk.com/valves/

[3] https://www.baesystems.com/en-uk/english-electric-canberra

H2 Aircraft Design

Cards on the table. I’m a believer. Despite the immense technical challenges, Hydrogen is a viable fuel for future large civil aircraft. That said, operational service of such revolutionary aircraft isn’t going to happen in a hurry.

Reading the history, Concorde was an incredible test of the boundaries of what was possible and that was met, but it didn’t come easy. Breaking new ground is never easy. [A common saying that’s maybe open to challenge]. In aviation making step-changes happens every decade. What’s nearly always required is exceptional determination, almost beyond reason, large sums of money and special people.

Control systems – no big deal. Mechanical components – evolution possible. Turning a gaseous fuel into high-levels of propulsive thrust – can be done. Building a one-off technology proving research vehicle. It’s happening. At least for the light and commuter class of aircraft.

None of this is enough. Because the gap between an aircraft that can fly and an aircraft that can be produced in the thousands and go on to make an operational living and build an impressive safety and reliability reputation, that’s still a million miles off.

Today, there’s artist impressions of all sorts of different H2 aircraft configurations. It’s like people painted pictures of Mars with imaginary canals, long before anyone knew what the planet looked like in reality. Innovation starts with ideas and not all of them are sound.

As I expressed in my last article, crashworthiness must be given much consideration when speculating about future designs. It’s not always explicit in aircraft certification, cabin safety being the exception, but studying the history of accidents and incidents is essential. One of the successes of the authorities and industry working together is to take lessons learned seriously.

I remember looking at the pictures of the wreckage of Air France Flight 358, which crashed on landing in Toronto, Canada[1]. The fact that there were no fatalities from that accident is a testament to good operations and good design practices. The Airbus aircraft burned out but there was enough time for passengers and crew to get away.

My thought is what kind of H2 aircraft configurations would permit the same opportunity?

Considering this large aircraft accident, and others like it, then there’s a message as to where fuel tanks might best be placed. There’re some aircraft configurations that would have little hope of providing the opportunity for rapid evacuation of hundreds of people.

So, in my mind, don’t attached large pressurised cryogenic fuel tanks to the underbody structure of an aircraft fuselage. However robust the design and build of such fuel tanks they would be unlikely to survive as well as the cabin passenger seats, namely 9g[2]. That would not provide a good outcome post-accident.

Maybe, like aircraft engines sitting on pylons off the wings, that too is a good place for fuel tanks.

[1] https://asn.flightsafety.org/asndb/322361

[2] https://www.easa.europa.eu/sites/default/files/dfu/NPA%202013-20.pdf

Societal Change and AI

Societal change is inevitable. It seems hack to analogise with reference to the printing press. Look what happened, an explosion of communication. Dominance of the book for centuries. Expanding literacy. Progressive shaping of society resulting in this era.

We are only where we are because we stand on the shoulders of the giants who went before[1]. Not just the giants. There is massive amount of human contribution that is never accounted. The unseen heroes and the occasionally rediscovered thinkers and doers.

Along the way of history those who battle the battle of glass half full or glass half empty chatter away. We are either in a glorious age or a minute away from Armageddon. Polar ends of our future, both stories have merit. Who has a crystal ball that works?

I’ve been aware of neural-networks and joked about Bayesian Belief Networks for at least two decades. Having been involved in the business of data analysis that’s no surprise. Even so the rapid advance of a multitude of different forms of artificial intelligence (AI) is a surprise.

Talking generally, we have this foolish mental picture of the world that everything is linear. Progression from one state to another takes proportionate steps forward. It’s a hangover from the analogue world which is where we were until the 1960s/70s.

This fetish for straight lines and normal curves is deeply embedded. It’s odd. Although a lot of rules in nature do have a linear form, one that Sir Isaac Newton would recognise, there’s far more that follows other rules.

In the last few weeks this fetish played out at a global scale. We are all treating climate change as if it’s a water clock. Drip, drip by drip the climate changes. A reaction to a progressive degradation. Yet, environmental reality might have a step change in degradation ahead.

In my view it’s right to try to vision ahead about the path AI technology might take. It’s right to consider more than progressive development and evolutionary change. Information systems have a habit of either falling into disuse or marching on at the pace of Moore’s law[2].

Another example. The math of Fourier transforms has been around a long time. Doing Fast Fourier Transform (FFT) in the 1970s required a couple of chunky cabinet full of power-hungry electronics. For the few, not the many. Today, every smart phone[3] in the world can crunch FFT algorithms. For the many, not the few.

Can we use a simple graphical representation to say where AI is going[4]? Will “intelligence” double every year or two? Well, I suspect that developments will go faster than a doubling. Like Moore’s law these conditions tend to become self-fulfilling. It’s a technological race.

[Why? To a machine there’s no sleep. To a machine there’s 86,400 seconds in a day. Everyone is meaningful and useful. To a complete and successful electronic machine only a tiny fraction of its operating time needs to be spent fixing itself. Or that might be one job left to us.]

POST: The impact of this high speed race makes interesting study U.S. Should Build Capacity to Rapidly Detect and Respond to AI Developments – New Report Identifies Workforce Challenges and Opportunities | National Academies

[1] Sir Isaac Newton, English scientist, “If I have seen further, it is by standing on the shoulders of giants.”

[2] https://www.asml.com/en/technology/all-about-microchips/moores-law

[3] https://www.bbc.co.uk/news/business-38320198

[4] https://www.nature.com/articles/d41586-024-03679-6

Next Generation with Practical Experience

Backwards and forwards the discussion goes on platforms like LinkedIn. Everyone recognises the expected demand for engineers. This century will be as much an engineering century as any century that has gone before. Science advances rapidly. New materials are available. Computation power is shooting off the charts. It’s now possible to design, build and test more systems to do more tasks than ever before.

The question is where’s the next generation of engineers going to come from?

Here’s one aspect of the debate that I find mildly irritating. Despite that discomfort, I’m prepared to be a hypocrite on this point. It’s to discuss future education and training with an almost blinkered reference to one’s own experience. For me, that’s to look back 45-years and then project forward. This is a natural tendency that should be handled with extreme care. However much it’s good to cherish past successes they do not guarantee future ones.

My first paid job involved Rotring[1] ink pens and pencils. Drawing film and large dyeline printers. Ammonia vapour filled the print room. It’s the sort of place the term “blueprint[2]” emerged. Drawing a myriad of small mechanical components used to make-up cabinets of electronics. I’d follow them through to the workshop where they would be turned into hardware.

That world has gone almost entirely. At that time, an infant was growing. A chunky electronic pen that could be used to move straight lines around on a bulky computer screen. That infant was computer aided design. Methodically and slowly computer digitisation was taking over. Soon the whole job description; engineering draftsman, disappeared into the history books.

Today’s infant is Artificial Intelligence (AI) or at least, if we discard the hype, massive infinitely flexible computing power. As a result, we have no idea how many jobs will next disappear into the history books. So, if I have a point to make it’s along the lines of being mighty cautious about what could inspire the next generation of engineers.

Moving to the next step in my early career path. Given that I made solid progress and having an exceptionally progressive employer[3], I moved through departments each time having a go at something new. My pathway to electronic design (analogue) was step by step.

I’ve pictured an oscilloscope because that’s one of those key steps. What it provides is a way of seeing what can’t normally be seen. Sitting in a classroom learning about frequency modulation, or such like, is necessary. Doing the sums to pass exams is essential. But nothing beats hooking-up a few bits of equipment on a workbench and seeing it for yourself.

So, that’s my recipe for inspiring the next generation of engineers. Create opportunities for them to see it for themselves. Even in the massively complex digital soup that we all swim in.

Theory is fine. Being able to visualise is the best tool. Or is that just me?

[1] https://www.rotring.com/

[2] https://youtu.be/7vnGY9vXgsQ

[3] https://en.wikipedia.org/wiki/Plessey

Harmonisation

There’s an example in of itself. I’ve used the British English spelling. Perhaps I should have standardised on the American spelling, namely Harmonization. Or does it matter at all given that the definition of the word remains the same, whatever. Oh, I can’t resist the temptation to say; you say Tomato, I say Tomato.

“You say tomato, I say tomato.

You eat potato and I eat potato,

Tomato, tomato, potato, potato,

Let’s call the whole thing off.”

Naturally, in the voice of Fred Astaire[1]. Nice though this is, my subject is not pronunciation.

Aviation is a highly regulated business. It’s been that since its potential for transporting huge numbers of people around the globe was recognised. Safety must be number one. Although, it’s not if you read the first few words of the all-important Chicago convention.

Article 1: Every state has complete and exclusive sovereignty over airspace above its territory.

In the minds of those who signed the convention it was sovereignty that took first place. That didn’t mean abusing the word “sovereignty” as has to often been done. Afterall, the whole basis of the Convention on International Civil Aviation was international cooperation. It still is.

Let’s put that to one side for a moment. One of the challenges of international aviation has been the different rules and regulations in place in each country. There’s a level of harmony in the standards of the International Civil Aviation Organization (ICAO). But ICAO is not a regulator and it’s for each country to interpret agreed standards within their domestic law.

Europe, or at least the European Union (EU) is different in this respect. Since there’s European law and an active European regulator then there’s common rules and regulation set for a regional grouping of countries. So far, Europe is the only region to go this far.

When it comes to aircraft airworthiness this has been a topic of a lot of discussion in the last four decades. In the 1990s, that discussion centred around the idea that a single worldwide code was a desirable achievement. That the time the two major entities engaged in the business of aviation rulemaking, and the maintenance of rules were the FAA (US) and the JAA (Europe).

A single worldwide code could greatly facilitate the movement of aviation produces around the globe. That done to ensure that common safety standards were maintained on every occasion. It proved hard to get to this utopian condition. That said, a great deal was achieved in the harmonisation of existing civil aviation codes. Today, we benefit from that work. I’d say we even take it for granted.

In around 2000, after much study, countries concluded that it was fine to seek some form of equivalence between respective rules rather than having to write done one single set of rules. Mutual recognition has flourished in the form of agreements between countries that has smoothed the path for the aviation industries.

That last major study of the pros and cons of harmonisation is now nearly a generation old. A lot has moved on. For one, in Europe the JAA transition to the EASA.

At the same time the manufacturing countries worked closely together to agree on measures to ensure that there was no great divergence in rules and regulations. Now subjects, like Safety Management Systems (SMS) became codified. However, sovereign countries continued to develop and maintain their own aviation rules and regulations.

International working groups often achieve remarkable commonality and convergence on detailed technical topics. Often because the few people who were deeply embedded in a technical subjects all knew each other and shared information relatively freely.

Discussion as to the viability of a single worldwide code has not completely faded into the past. In fact, there’s some good reason to breath life back into this historic debate. Here’s what’s added to the dynamics of the situation:

Ongoing moves from prescriptive rules to more performance-based rules,
Entirely new products in development, like eVTOL aircraft,
Interdependency, interconnection, and integration all increased since 2000,
Security and safety are becoming inseparable,
Digitisation is changing the ways that we ensure that an aircraft is airworthy.

If you have knowledge of, and thoughts on this subject, I’d be happy to hear from you.

[1] https://youtu.be/LOILZ_D3aRg