Category: Aviation

Communication Prevents Disasters

It’s often forgotten that there’s a need to repeat messages. We are not creatures that retain everything we see and hear. There are exceptional people, it’s true, those who cram away facts and have an amazing level of recall. Often that’s my reaction to watching students leading teams on University Challenge[1]. How on earth do they know those obscure facts?

Most of us do not respond well to those who say, “Well, I told them once. I’m not going to tell them again.” That line is probably one of the most misguided utterances a teacher can make. Like it or not, this approach is part of our heritage. Past ages, when deference was expected, listening was mandatory, and misremembering was entirely the listener’s fault.

We’ve had a cultural shift. Our complex technological society doesn’t work in a command-and-control way. Too many disasters can be traced to miscommunications and misunderstanding. Now, the obligation exists on those delivering a message to go some way to ensure that it’s received with a degree of comprehension. That’s when repetition has a role to play.

One of the pillars of Safety Management Systems (SMS) is Safety Promotion. It’s the Cinderella of the aviation safety world.

Why do I say that? Experience for one. It’s much easier to get policy made and funding for the “hard” sciences like data acquisition, analysis and decision-making systems. These are often perceived as providing tangible results. Actionable recommendations that satisfy the need to be recognised as doing something. Even if that something is questionable.

Communication is key to averting disasters. It’s no good having pertinent information and failing to do anything with it, other than file it. The need to know is not a narrow one. Confined to a specialist few.

Let’s go back to 2003 and the Space Shuttle Columbia accident[2]. This craft was destroyed in a disaster that claimed the lives of its crew. The resulting investigation report is extremely compressive, if slightly overwhelming, but it has some key points to make.

To quote, “That silence was not merely a failure of safety, but a failure of the entire organization.” [Page 192]. In other words, the hidden concerns and internal machinations of an organisation can smother safety messages and led to failure. Since 2003, it’s sad to say that there are multiple occasions when what has been learned has been ignored. The impact has been devastating.

So, to shape the future let’s remember the Cinderella of the aviation safety. Discovering problems is not enough. It’s vital that practical solutions and good practice gets promoted. That needs to be done forcefully and repetitiously.

NOTE: This is, in part, a reaction to watching this video presentation. https://acsf.aero/an-unforgettable-closing-to-the-2025-acsf-safety-symposium-with-tim-and-sheri-lilley/

[1] https://www.bbc.co.uk/programmes/b006t6l0

[2] https://ntrs.nasa.gov/api/citations/20030066167/downloads/20030066167.pdf

My First US Adventure

Let’s wind the clock back. My first trip to the US. It was a big adventure. One that I’d recommend to anyone in their 20s. The trip was a Pam Am fly-drive affair. A travel package that took me and three friends from London Heathrow to Seattle and back. In 1981, I had no idea that I’d be returning to Seattle numerous times in the following decade.

I keep a personal flight logbook. It’s a simple way of keeping track of the dates, times and places. Memory can be unreliable. When 40 years or more has past recollections of individual trips get jumbled up. Although this one is difficult for me to mistake.

We took off in the afternoon and flew across the Atlantic on flight PA 123. Slightly being in awe of the mighty Boeing 747-100. It was the largest aircraft doing that route on a regular basis.

Sadly, the Lockerbie bombing occurred 7-years later to a similar transatlantic Pan Am flight. The airline that brought the Boeing 747 to life didn’t survive after that tragic event.

One of the advantages of being a sandwich student was the ability to earn. To put some money away. To have the funds to plan an exploration like this trip without depending on the bank of mum and dad. To keep the costs down the four of us shared a car, the driving and the motel rooms along the way. In fact, we had a detailed itinerary that didn’t leave much slack time at all. Our travel planning was meticulous. I’d even arranged to visit an offshoot of the Plessey company in the Los Angeles suburbs. It was a real eyeopener. A maker of precision metals for the aerospace industry.

We arrived in Washington State only a year after the deadliest volcanic eruption[1] in US history. Naturally, being the students we were, we drove as close to the devastated area as the open roads would let us. I took pictures of that too. Views of forests felled like matchsticks.

We packed an enormous amount into August 1981. Returning to our final year as soon as we got back. This trip always reminds me that if you plan well and are determined enough you can do a hell of a lot in a short time. We drove over 6000 miles and took in a lot of the West Coast.

[1] The Mount St. Helens major eruption of May 18, 1980.

Transform of Future Careers

My education was an industrial one. I guess I was fortunate. No “A” levels for me.

Part of my apprentice programme was to move around the different departments of a major electronics company. That included a range from demanding technical areas, testing new designs, to the everyday pressure of a print room run by an ex-Army man who ran it as if he’d never left the Army. Yes, print rooms were once a staple part of an engineering company. Huge dyeline machines that constantly ponged of ammonia twinned with the noisiest dot-matrix printers ever made. I even got to learn some COBAL[1] with the business unit that put together our payslips. Amazingly enough I was introduced to mathematical concepts, like Fast Fourier Transforms (FFT), at a time when the digital logic needed to implement such algorithms consisted of large cabinet loads of discrete electronics. Now, my simple mobile phone can crunch numbers in this way.

Several weeks here, and several weeks there. One excursion meant spending hot summer days in the Mendip Hills at a quarry testing equipment in deep water. Another meant time working in a former brick-built railway shed that served as a small machine shop.

Of all the different experiences that I had in those formative years (16-18 years) the one that I’ll never forget was a secondment to a London based factory. The company’s training officer recognised that this small village country boy needed to go to the big city. Uppark Drive, Ilford no longer exists as a manufacturing plant. That’s no surprise. In the late 1970s that factory handled the company’s long-lived products. Technology that has gone forever.

Anyway, this is not so much about me. What I’m led to speculate about is what sort of modern-day engineering apprenticeship offers. Does it offer the variety of experiences that I had? Is industrial sponsorship as generous and altruistic as it once was? Do industry and government work hand in hand to ensure a future workforce has the skills that are needed?

Simply the answer is probably “no”. In fact, the structure and organisation of design and manufacturing organisations has changed dramatically. In aerospace there are some companies that have a major factory with every facility at their heart but most subcontract extensively. Colleges have been turned into educational shops, paid by student numbers.

Here’s a thought. It’s not so much what’s taught that’s key as much as the exposure to a variety of ways of thinking and working. A variety of exposure give a student a toolbox from which they can then draw. Finding interesting work will depend on adaptation and repurposing past skills. That’ll be the only way to assure the world doesn’t pass by at an ever-increasing pace.

I’m sure that advances in artificial intelligence (AI) will affect everyone[2]. The idea that all AI will do is displace people is wrong. It just means that, like my recollections above, the types of activities that needs to be done will be entirely different in 2065. Unless I’m highly unusual, I will be long gone. But if you are 25 years old this is worth a thought.

[1] https://archive.org/details/historyofprogram0000hist/page/n7/mode/2up

[2] https://nap.nationalacademies.org/download/27644#

Tragic Helicopter Crash

The record of sightseeing helicopters is not a good one. In the most recent case 6 people perished as helicopter crashed into the Hudson River in New York City. It’s with a heavy heart that I offer my condolences to the family and friends of those involved. These are devastating events for all concerned.

It’s certainly far to early to say why this helicopter fell from the sky. Eyewitness reports suggest a catastrophic occurrence. Also, that the helicopter tumbled and hit the water inverted. Again, suggesting an occurrence where the pilot had no opportunity to avoid the outcome.

Initially, the indications are that the local weather was not a significant factor in the accident. Also, reports are that no other aircraft was involved. In this fatal accident the US National Transportation Safety Board (NTSB) will be on the scene as they manage the technical investigation. They have already published initial information.

Given the size and nature of operations there will be no Flight Data Recorder (FDR) installed on this helicopter. There is a strong argument for requiring light weight flight recorders on small helicopters. It will be interesting to read of what electronics are recovered from the accident site. Images from a mobile phone may be most useful to the investigators.

The helicopter’s maintenance records will be reviewed for indications of mechanical problems. However, it is highly unusual for a complete rotor system to fall apart in flight. Mechanical failures often have some precursors that give an indication that all is not well.

The list of Bell 206 type helicopter accidents and incidents is long[1]. That’s not an indicator of their relative safety. This is a popular single engine small helicopter with a long history. Both civil and in other variants, military. First flight dates to 1966. It’s going back a while, but I clearly remember a sightseeing flight I took on such a helicopter back in the 1980s.

This type of small helicopter is often operated in difficult conditions. They have the advantage of being highly maneuverable. However, there are maneuvers that can case serious problems. The term “mast bumping” was used by the US Army[2]. In the worst cases this results in catastrophic occurrences.

One of the factors in such accidents and incidents is a significant change in the helicopter’s center of gravity and an inappropriate response to that condition.

POST 2: Pictures of the recovery of the rotor system from the river suggest structural failure. It’s as if the rotating mechanical parts ripped themselves from the body of the helicopter. Bell 206 L-4 helicopter crash, Jersey City, New Jersey (April 10, 2025) | Flickr

POST 1: Social media is littered with theories, as per usual. One seems highly unlikely. Namely, fuel exhaustion. Another, concerning a strike of a flock of birds over the river is worth investigation. In that possible case evidence will surely be easily uncovered.

[1] https://asn.flightsafety.org/wikibase/495847

[2] https://youtu.be/_QkOpH2e6tM?si=AtMfqztc_cjrUOSm

Safety Analysis

In discussions about safety one model is often called up. Its simplicity has given it longevity. It also nicely relates to common human experience. The model is not one of those abstract ideas that take a while to understand. If you have been on a safety training course, a lecturer will give it couple of minutes and then use it to draw conclusions as to why we collect and value safety data.

On illustration, and it’s a good one for sticking in the memory, is a picture of a big iceberg. Most of an iceberg is underwater. One the surface we only see a fraction of what is there. This is the Heinrich pyramid. Or Heinrich’s Law[1] but it’s not really a law in the sense of a complete mathematical law.

The logic goes like this. In discissions about industrial major accidents, there are generally a lot more minor accidents that precede the major ones. Although this was drawn up in the 1930s the model has been used ever since. And we extend its useful applicability to transport operations as much as workplace accidents.

Intuitively the model seems to fit everyday events. Just imagine an electrical cable carelessly extended over the floor of a hanger. It’s a trip hazard. Most of the time the trips that occur will be minor, annoying events, but every so often someone will trip and incur a major injury.

What we can argue about is the number of precursor events that may occur and their severity. It wouldn’t be a simple universal ratio, either. Heinrich said there were generally about 30 accidents that cause minor injuries but 300 accidents with no injuries. A ten to one ratio.

Forget the numbers. The general idea is that of the iceberg illustration. Underlying that example of the pyramid is the notion that there are a lot more low severity events that occur before the big event happens. Also, that those low severity events may not be seen or counted.

It’s by attempting to see and count those lesser events that we may have the opportunity to learn. By learning it then becomes possible to put measures in place to avoid the occurrence of the most destructive events.

In British aviation I will reference the 1972 Staines air accident[2]. A Brussels-bound aircraft took off from London Heathrow. It crashed moments later killing those onboard. One of the findings from this fatal aircraft accident was that opportunities to learn from previous lesser events were not taken. Events not seen or counted.

Thus, Mandatory Occurrence Reporting[3] was born. Collecting data on lesser events became a way of, at least having a chance of, anticipating what could happen next. Looking at the parts of the iceberg sitting under the water.

How many fatal accidents have been prevented because of the safety analysis of data collected under MOR schemes? If only it was possible to say.

[1] https://skybrary.aero/articles/heinrich-pyramid

[2] https://www.bbc.co.uk/news/uk-england-surrey-61822837

[3] https://www.caa.co.uk/our-work/make-a-report-or-complaint/report-something/mor/occurrence-reporting/

From Prescription to Performance-Based Regulation

One regulatory development that has stuck since the start of the new century is the idea that we need to transition from prescriptive requirements to performance-based requirements. It’s not too hard to understand where the motivation to change has come from but there are several strands to the path. Here’s three that come to mind.

For one, the intense dislike of overbearing governmental regulators who adopt an almost parental attitude towards industry. It’s true that safety regulatory bodies have a duty to serve the public interest. The difficulty arises in interpreting that brief. Not as police officers sometimes did, imagining everyone as a potential miscreant.

My experience as a regulator started at a time when traditional institutional approach was quite common. There was a respectful distance between the airworthiness surveyor or operations inspector and the aviation industry that they oversaw. I think, even the term “surveyor” was one inherited from the insurance industry at the birth of flying.

A wave of liberalisation swept into the 1980s. It was an anathema to those who started their careers as men from the Ministry. The idea that regulators should be in a partnership with industry to meet common goals was not easily accepted. Undoubtably a change was necessary and, naturally, easier for an up-and-coming generation.

The next move away from regulatory prescription came as its value declined. That is, not that there will not always be an element of prescription by matter of the written law. However, for detailed technical considerations it became less and less practical to say, this is the way it must be. The minute decision-makers were faced with the complexity of a microprocessor it become clear that it’s not effective to simply prescribe solutions.

Much of the changes that took place can be traced to the evolution of system safety assessment and the use of probabilistic methods in aviation. In mechanics, prescribing a safety guard for a chain drive is straightforward. For complex electronics saying when a flight system is safe enough requires a different approach. Regulators are now driven to set objective rather than dictate solutions.

My third point is a future looking one. Whatever the history and heritage of aeronautical innovation, it’s true that a “conservative” but rapid adoption of new technology continues to be a source of success. Great safety success as well as commercial success.

Hidden amongst the successes are products, and ways of working that don’t meet the grade. The joke goes something like this: “How can I make a fortune in aviation?” Answer: “Just start with a big one.” Implicit in this observation is a wiliness to innovate at risk. That means, amongst many things, having confidence, adaptability and not be so constrained as to be assured failure. An objective or performance-based approach to safety regulation opens opportunity to innovate more freely whilst still protecting the public interest in safety.

There’s no fixed destination for regulatory development.

1985 to 2025 Trends

On reading J. C. Chaplin’s paper on the first 100-years of aviation safety regulation in the UK[1], it struck me that the journey from the 1910s to the 2010s was one of constant change. That change has not slowed down. In fact, the last 40-years of my aviation career have seen dramatic technological changes that have demanded ever new regulatory methods and practices.  

Overwhelmingly aviation history writings obsess about the early days of flying or the start of the jet age. It’s as if those periods were so dominated by great pioneers that nothing worthy has happened since. I exaggerate for effect, but I think you get the meaning of my comment.

So, what of the race from the 1985 to the 2025? I think that is useful period to look at. One of the reasons is that those years are mark the transition from an analogue era to a digital one.

The early 1980s saw experimentation with the potential for digital technologies, most particularly fly-by-wire systems. Quickly the military understood the increase in aircraft performance that could be gained by use of such technologies. Groundbreaking was Concorde in that it demonstrated that critical electronic control systems could safely go into everyday operation. That project drove the development of new regulatory methods and practices. 

A turning point occurred in the mid-1980s. That silicon revolution that impacted so much of life was dramatically put to use in civil aviation. Computing power had so miniaturised and become affordable so that past theoretical possibilities could now be practically realised.

The Airbus A320 aircraft first flew in 1987. It was a shaky start. Not everyone was convinced that safety critical systems were indeed safe. The not so obvious discovery that the human factor was even more important for a computerised aircraft. Learning to adapt and adjust ways of operating didn’t happen overnight.

The lesson is that learning lessons must be part of the process. Through applying continuous improvement, the Airbus A320 family has grown ever since.

Maybe there needs to be a short paper to cover civil aviation safety regulation from 1985 to 2025. It’s needed now. It’s needed because the next 40-years are going to see equally dramatic changes. In the time to come the main driver will be the environment.

[1] https://www.aerosociety.com/media/4858/safety-regulation-the-first-100-years.pdf

The Revolutionary Role of Hydrogen

Hydrogen has a history with aviation. What could be better. A gas that is so light. So easily produced and with no need heat it up. With a lightweight gas-tight bag and a fair amount of rope, balloon construction took-off. Literally. The proof that hydrogen gas could lift a balloon goes back to the 1780s in France.

Sadly, the downside of this gaseous element is its propensity to combine with other elements. In fact, where would we be without liquid water. On this planet, that most basic and prolific combination of hydrogen and oxygen. Not so much sadly but more luckily.

Step forward about 250 years and we have a different vision for hydrogen in aviation. If it’s combined with the oxygen in the air that we breath, we get nothing more noxious than water. Since, the other forms of combustion, that populate our everyday lives, is distinctly noxious, surely hydrogen has a lot to offer. Talk about downsides. Burning fossil fuels is distinctly unsustainable. Polluting the atmosphere.

This week, I was looking out to sea. At the English Channel (No name changes there, I see). Standing on the pebble beach at Budleigh Salterton. They ought to have an award just for that name. It’s a small seaside town in Devon. The towns cliffs are part of a World Heritage Site, namely The Jurassic Coast[1]. 

Forget the 250 years of humans flying, cited above. About 185 million years of the Earth’s history is for all to see on the Devon and Dorset coast. When we say “fossil fuels” what we mean is that we are living off the back of Earth’s history. Society powers modern life on dinosaur juice. Well, not exactly but plant and animal life from hundreds of millions of years ago. How crazy is that?

Hydrogen, on the other hand, is one of the most abundant elements. It’s everywhere.

Modern day dinosaurs (politicians and pundits) insist that we continue to exploit dinosaur juice until it’s all gone. That’s putting aside any concerns about returning all that carbon to the Earth’s atmosphere. Carbon accumulated over millions of years.

Hydrogen can be a clean fuel. The problem is that saying that and then doing it are two different things. There are complexities that come with using Hydrogen as a fuel. It might be reasonably easy to produce, in multiple different ways, but it’s not so easy to transport.

Producing leak proof systems for transport and storage requires innovative thinking. We can’t just treat it with the familiarity of conventional fuels. Whole new regimes are going to be needed to get Hydrogen from where it’s produced to where it’s needed.

Producing leak proof systems for aircraft is a challenge. Given the odourless and invisible nature of this light gas, accurate and extensive detection systems are going to be needed. If the gas is to be consumed by fuel cells to produce electricity, then there’s going to be a constant struggle against complexity and significant expenditures.

What is reassuring is that none of the above is insolvable. At this time in history, we have the materials technology and control systems that make Hydrogen a viable clean fuel.

[1] https://jurassiccoast.org/

Understanding Aviation Safety

The recent dramatic events in Toronto brought to mind the equally dramatic event of Air France Flight 358 back at the latter half of 2005. Then a large aircraft was destroyed but the crew and passengers got away without fatalities. The combination of bad weather and poor decision-making led to a catastrophic runway excursion.

I remember that the year 2005 shook the aviation community. There was a whole succession of fatal aircraft accidents across the globe. In Europe, Helios Airways Flight 522 was particularly tragic. Errors led to the crew suffering hypoxia and as a result the aircraft and everyone onboard was lost. In Italy, lives were lost as an ATR72 aircraft ran out of fuel and plunged into the Mediterranean Sea near Palermo.

West Caribbean Airways Flight 708 fell from the sky killing all on-board. Kam Air Flight 904 hit a mountain killing all on-board. In Indonesian, Mandala Airlines Flight 091 crashed. A few passengers survived but many people were killed on the ground.

I sincerely hope that 2025 is not going to turn into another 2005. However, I do take the view that there is a cyclic element to the occurrence of fatal accidents. We are often proud to be able to say that the time (number of years) between one cluster of aviation accidents and another grows as overall safety improves but we are a long way from zero-accidents.

The global aviation industry is an incredibly safe industry when considering how many passengers are carried every year. However, zero-accidents remain an illusion however it might be touted as the ultimate goal.

As safety practitioners try to be ever more pro-active in our safety regimes there’s inevitably a reactive element to aviation safety. The aftermath of the 2005 experiences led to ICAO holding its first high-level safety conference in 2010 in Montréal. There have been two more such conferences since. One in 2015 and one in 2011.

The results have been to push the aviation industry towards a more pro-active management of safety. It’s not just the industry. In cases, the regulatory weaknesses that exist in individual States has needed to be given attention.

Add all this up over the last 20-years and you would expect everyone to be pro-actively managing aviation safety. Sadly, that’s not the case as some States and organisations are still managing the transition to a more pro-active approach. Some are so resource constrained that they are more inclined to talk about aviation safety than to act upon it.

Regulatory weaknesses exist in some unlikely places. Additionally, with the fashion of the time being to cut “red tape” at every opportunity, more troubles might be just over the horizon.

I’d like to see a break between the association of what is regulatory and what is considered bureaucracy. The two are not necessarily the same. Regulation and standards are synonymous. And what we know is that there is no successful complex industry without standards.

Please let’s not wait for the next accident report to tell us what to do.

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/