Air Taxi 3

Urban mobility by air, had a flurry of success in the 1970s. However, it did not end well.

Canadian Joni Mitchell is one of the most celebrated singer-songwriters and my favourite. She has tapped into the social and environmental issues that have concerned a lot of us for decades. Of her large catalogue, I can’t tell you how much I love this song[1]. The shear beauty of the lyric.

Anyway, it’s another track on the album called “Hejira” that I want to refer. When I looked it up, I found out, I was wrong. The song I want to refer to is on the 1975 album “The Hissing of Summer Lawns”. The song “Harry’s House[2]” contains the line “a helicopter lands on the Pan Am roof like a dragon fly on a tomb.” Without going into what it’s all about, the lyrical image is that flying from a city skyscraper roof was seen as glamorous and the pinnacle of success.

In 1970, prominent aviation authorities were talking about the regulatory criteria needed for the city-centre VTOL[3] aircraft of the future. Then on the afternoon of 16 May 1977, New York Airways Flight 971, a Sikorsky S-61 helicopter, crashed[4] on Pan Am’s building rooftop heliport[5]. That ghastly fatal accident reset thinking about city centre operations air transport operations.

So, what’s different 50-year on? Proposals for city centre eVTOL operations are much in the News. City planners are imagining how they integrate an airborne dimension into public transport operations. Cars, busses, trains and eVTOL aircraft may all be connected in new multimodal terminals. That’s the city transport planners’ vision for less than a decade ahead.

For one, the vehicles are radically different. Yes, the physics of flight will not change but getting airborne is quite different between a conventional large helicopter and the plethora of different eVTOL developments that are underway across the world.

Another point, and that’s why I’m writing this piece, is the shear amount of safety data that can be made available to aircraft operators. Whereas in the 1970s, a 5-parameter flight recorder was thought to be neat, now the number of digital parameters that could be collected weighs in over thousands. In the 1970s, large helicopters didn’t even have the basic recording of minimal flight data as a consideration. The complexity in the future of eVTOL will be, not how or where to get data but what to do with all the data that is streamed off the new aircraft.

Interestingly, this changes the shape of the Heinrich and Bird “safety pyramid” model[6]. Even knowing about such a safety model is a bit nerdy. That said, it’s cited by specialist in countless aviation safety presentations.

Top level events, that’s the peak of the pyramid, remain the same, but the base of the pyramid becomes much larger. The amount of safety data that could be available on operational occurrences grows dramatically. Or at least it should.

POST: Growing consideration is being given to the eVTOL ecosystem. This will mean a growing need to share data Advanced Air Mobility Portal (nasa.gov)


[1] https://youtu.be/nyj5Be5ovas

[2] A nice cover https://youtu.be/bjvYgpm–tY

[3] VTOL = Vertical Take Off and Landing.

[4] https://www.nytimes.com/1977/05/17/archives/5-killed-as-copter-on-pan-am-building-throws-rotor-blade-one-victim.html

[5] https://www.thisdayinaviation.com/16-may-1977/

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

Air Taxi 2

As a quick effort at simple research, I looked at several local government websites searching for Air Taxi or Urban Air Mobility (UAM) or Advanced Air Mobility (AAM). The result was lots of blanks with one or two exceptions[1][2]

There’s numerous articles about e-scooters and how they might be integrated into cityscapes.

Addressing local governments, much of what has been published to date concerns the use of drones. Yes, the use of drones is happening here and now, so this is not such a surprise. However, to me, this was a reminder that the frenetic world of aviation often discussed the future in rooms full of like-minded people. Embracing a wider audience is overdue.

In the case of UAM/AAM, innovations in civil aviation are move beyond airports, upper airspace, and specialist technical interest. If the electrification of flight is to take hold it will touch the lives of many more people than conventional commercial aviation.

These new aviation developments will generate new business models and offer new services. This is challenging stuff. It’s clear to me that, without the agreement of local authorities such enterprises will be dead before they start.

National governments may take a regulatory approach that imposes on local governments. That would be ill advised and ultimately unsustainable. A cooperative partnership would open a smooth transition from transport novelty to accepted everyday part of mobility.

Local authorities will need to adapt their formal local plans to include planning considerations of zoning, land-use, multi-modal matters, environmental impact, construction, utilities/support infrastructure, public privacy and much more.

Local government is a partner in risk management too. Just as highway authorities wrestle with improving road safety so, no doubt, UAM/AAM accidents and incidents will be on their agenda.

Fostering public-private partnerships is talked about but few examples have moved beyond theory and into practice.

POST 1: These issues have been highlighted at ICAO this year Urban Air Mobility and the Role of Air Transport – ICAO 2022 Innovation Fair – ICAO TV

POST 2: The organisation is looking at possible future operations https://varon.aero/

POST 3: People taking a holistic view http://www.supernal.aero


[1] https://www.civataglobal.org/

[2] https://www.urbanairmobilitynews.com/global-map/

Air Taxi

My daily routine once comprised of walking across a bridge over the Rhine to an office in Ottoplatz in Köln-Deutz[1]. That’s in Cologne, Germany on the eastern side of the river.

In the square outside the railway station is a small monument to a man called Otto. A small monument marking a massive transformation that took place in the way transport has been powered for well over than a century. This monument honours Nicolaus August Otto who created the world’s first viable four-stroke engine in 1876.

Today, the internal combustion engine hasn’t been banished. At least, not yet and Otto could never have known the contribution his invention would make to our current climate crisis. But now, rapid change is underway in all aspect of transport. It’s just as radical as the impact of Otto’s engine.

As the electrification of road transport gathers apace so does the electrification of flying. That transformation opens new opportunities. Ideas that have been much explored in SiFi movies now become practically achievable[2]. This is not the 23rd Century. This is the 21st Century. Fascinating as it is that in The Fifth Element the flying taxi that is a key part of the story, has a driver. So, will all flying cars of the future have drivers?

I think we know the answer to that already. No, they will not. Well, initially most of the electric vehicles that are under design and development propose that a pilot (driver) will be present. Some have been adventurous enough to suggest skipping that part of the transition into operational service. Certainly, the computing capability exists to make fully autonomous vehicles.

The bigger question is: will the travelling public accept to fly on a pilotless vehicle? Two concerns come up in recent studies[3][4]. Neither should be a surprise. One concerns passengers and the other concerns the communities that will see flying taxies every day of the week.

Public and passenger safety is the number one concern. I know that’s easy to say and seems so obvious, but studies have show that people tend to take safety for granted. As if this will happen de-facto because people assume the authorities will not let air taxies fly if they are unsafe.

The other major factor is noise. This historically has prevented commercial public transport helicopter businesses taking-off. Strong objections come from neighbourhoods effected by aircraft constantly flying overhead. Occasional noise maybe acceptable but everyday operations, unless below strict thresholds, can provoke strong objections.

So, would you step into an air taxi with no pilot? People I have asked this question often react quickly with a firm – No. Then, after a conversation the answer softens to a – Maybe.


[1] https://www.ksta.de/koeln/innenstadt/ottoplatz-in-koeln-deutz-eroeffnet–das-muss-nicht-gruen-sein–2253900?cb=1665388649599&

[2] https://www.imdb.com/title/tt0119116/

[3] https://www.easa.europa.eu/en/newsroom-and-events/press-releases/easa-publishes-results-first-eu-study-citizens-acceptance-urban

[4] https://verticalmag.com/news/nasa-public-awareness-acceptance-of-aam-is-a-big-challenge/

Next Please

There’s no celebration. No fanfare. Today, the UK get a new PM. The 4th in 6-years. We have seen Cameron, May, come and go. Now Johnson is going in favour of Truss. If there’s a celebration, it’s that Johnson is going out of Number 10 Downing Street. The removal van is, no doubt, fully laden.

This is a transition that needs to be made as quickly as possible. For too long the Johnson cabal has been lingering and doing little of any use to the nation. However, the jobs are distributed it’s a time when decisions must be made fast, but with a degree of smart flexibility.

Truss has none of Johnson’s ability to bluff and shtick. The new PM has a delivery that’s wooden and gaff prone. Nevertheless, Tuss has beaten others who would dearly love to be in the hot seat. Although, there’s good reason to question why anyone sane would want to be PM in September 2022, given the vast size of the in-tray that is waiting.

Smaller taxes and smaller Government may have been Truss’s shop window to Tory members but that’s not what’s necessary to dig the country out of the doldrums. This is a time for intervention. We have markets that are actively working against the interests of the British people.

Denying the aftereffects of Brexit also needs to go in the dustbin. It’s only by recognising a problem that a better path can be taken.

The last thing we need is a laissez-faire leadership. The textbooks of the Reagan era do not contain the solutions to the problems of the 2020s. Immediate changes to the energy market are needed. Regulation is a major part of those changes. Not micromanagement but structural change. The accumulation of huge profits because of our peculiar regulatory structure can’t continue.

On this momentous day, change must happen. However, as a word of caution, that transformation must not disregard the real and urgent nature of climate change. If our hot summer wasn’t an indicator sufficient to catch the attention of the new PM, and whoever is appointed as energy secretary, then look at what’s happening in Pakistan[1].

Winter is coming. Short-term measures must prepare us for winter, but the long-term perspective is vital. Not only do we need to decarbonise but reducing demand for energy for heating is achievable. For too long the benefits of improving Britain’s housing stock have been neglected. We don’t need more spiel and the hands-off approach should be for the dustbin.


[1] https://www.msn.com/en-gb/news/world/pakistan-floods-more-than-450-children-killed-in-e2-80-98horror-show-e2-80-99-with-death-toll-feared-to-rise-further/ar-AA11uXnL

Sun & Wind

My morning routine includes switching on the radio. That already marks me down as being of a certain age. News and current affairs isn’t always a cheerful way to start the day but, at least, as a result I feel a bit better informed about the world and its ways.

Listening to Vince Cable[1], at the end of the BBC’s Today programme this morning[2] I agree. [At run time 2:37]. Sir John Vincent Cable, yes that makes me even more inclined to listen to him, has a wealth of knowledge and experience and puts his case well.

Yes, we have had four major shocks to the British economy. The banking crisis, Brexit, COVID pandemic, and war in Europe. Amongst these Brexit was self-inflicted and has cost the UK a great deal. To lump on top of all that we have had incompetence in Government the like of which hasn’t been seen for decades.

The blatant idiocy of suggesting that the answer is fracking to produce more gas and more exploratory drilling is needed are the ultimate in short-term planning. The UK is not the US. Believe it or not, there is a global climate crisis and burning more fossil fuels makes it worse. Short-term planning is one of the reasons that the UK economy is underperforming. Proposing more of that approach is to further embed reckless incompetence.

Vince is right. We should make it easier to build onshore wind turbines in the UK. I’m not saying completely deregulate the planning systems. That would be entirely foolish. However, in local development plans we have ridiculous absurdities that name wind turbines and solar farms as a particular danger to the character of the landscape. So, any proposal that is brave enough to come forward gets slapped down immediately. Local politicians run for the hills.

Like all such regulatory issues, there needs to be a balance struck. There are numerous places in the UK were wind turbines and solar farms have a great deal more positive impact than negative. Proposals for renewable energy developments should be given a leg up. The UK is blessed with renewable energy assets in wind, seas, rain, and enough sun to make a difference.

I am first in-line to defend the beauty of our countryside but not everywhere is equal in that respect. Not only that but compared to nuclear power stations of any size, wind turbines and solar farms can be removed after a life of service with little sign of their former presence.


[1] https://en.wikipedia.org/wiki/Vince_Cable

[2] https://www.bbc.co.uk/sounds/play/m001bbsv

Energy cap

The letters “Of” have been used as shorthand for “Office of” in the names of several regulators in the UK. There are at least two of them that are gaining an unparalleled reputation for incompetence[1]. Maybe, I’m being unfair. Afterall, a regulator can only do what the legislation that created it will permit it to do. They are not lawmakers. They can only interpret the law in respect of their own responsibilities. That law, however amended, is relatively stationary in the face of events.

One way of explaining what has happened is to admit that the ethos and rules in place were devised to serve past times. In the world of services provided by industry, the environment has changed dramatically, in more ways than one. A cacophony of events, Brexit, recuring political ineptitude, war, and climate change have made the framework created for British regulation obsolete.

It’s like trying to use a Thatcher / Blair era computer in the world of today’s internet and mobiles.

Now, what’s clear is that we have a bunch of Ministers who haven’t a clue what to do when faced with this problem. Conservatives keep a picture of Sid[2] on their bedroom walls.

The call has come from the Greens to nationalise everything[3]. This too is an inept solution to current problems. This was the dogma that Labour once held dear. How the political landscape changes.

Despite the calamities befalling us, we must get off fossil fuels. Again, Conservative politicians are on the wrong page. Britons needs encouragement to switch and insulate[4] not to stoop to fossil fuels industry lobbyists. The notion that the solution to a painful recession is to burn the future is absurd.

Let’s get out of the rut. Defending, and being constrained by a framework of organisation that’s out of date is no use to anyone. That is why the Liberal Democrat proposal to freeze the energy price cap is a good start. We desperately need to buy time, with escalating inflation, to come up with a new regulatory scheme. One that works for customers. One that works for the environment. One that works for you and me.


[1] Ofgem – the Office of the Gas and Electricity Markets and Ofwat – the Water Services Regulation Authority

[2] To encourage individuals to become shareholders, the gas privatisation offer was advertised with the “If you see Sid…Tell him!” campaign.

[3] https://www.bbc.co.uk/news/uk-politics-62577830

[4] Home insulation has been slashed by the current Government

Safety Performance Indicators

What’s happening? Two words, and what seems like the easiest question in the world. Open your phone, look at the screen and a myriad of different sources of information are screaming for your immediate attention. They are all saying – look at me, look now, this is vital and don’t miss out. Naturally, most of us will tune out a big percentage of this attention-grabbing noise. If we didn’t life would be intolerable. The art of living sanely is identifying what matters from the clutter.

So, what happens in aviation when a Chief Executive or Director turns to a Safety Manager and askes – what’s happening? It’s a test of whether that manager’s finger is on the pulse, and they know what’s happening in the real world as it happens.

This is a place I’ve been. It’s a good place to be if you have done your homework. It’s the way trust is built between the key players who carry the safety responsibility within an organisation.

One of the tools in the aviation safety manager’s toolbox is that of Safety Performance Indicators (SPIs). In fact, it’s part of an international standard[1] as part of a package for conducting safety assurance. Technically, we are talking about data-based parameters used for monitoring and assessing safety performance.

The ideas are simple. It’s to create a dashboard that displays up-to-date results of safety analysis so that they can be viewed and discussed. Like your car’s dashboard, it’s not a random set of numbers, bar-charts, and dials. It should be a carefully designed selection of those parameters that are most useful in answering the question that started this short blog.

That information display design requires great care and forethought. Especially if there’s a likelihood that serious actions will be predicated on the information displayed. Seems common sense. Trouble is that there are plenty of examples of how not to do this running around. Here’s a few of the dangers to look out for:

Telling people what the want to hear. A dashboard that glows green all the time it’s useless. If the indicators become a way of showing off what a great job the safety department is doing the whole effort loses its meaning. If the dashboard is linked to the boss’s bonus, the danger is that pressure will be applied to make the indicators green.

Excessive volatility. It’s hard to take indicators seriously if they are changing at such a rate that no series of actions are likely to have an impact. Confidence can be destroyed by constantly changing the tune. New information should be presented if it arises rapidly, but a Christmas tree of flashing lights often causes the viewer to disbelieve.

Hardy perennials. There are indicators, like say; the number of reported occurrences, which are broad brush and frequently used. They are useful, if interpreted correctly. Unfortunately, there’s a risk of overreliance upon such general abstractions. They can mask more interesting phenomena. Each operational organisation has a uniqueness that should be reflected in the data gathered, analysed, and displayed.

For each SPI there should be an alert level. It can be a switch from a traffic light indication of green to amber. Then for the more critical parameters there should be a level that is deemed to be unacceptable. Now, that might be a red indicator that triggers a specific set of significant actions. The unscheduled removal or shutdown of a system or equipment may be tolerable up to a certain point. Beyond that threshold there’s serious safety concerns to be urgently addressed.

The situation to avoid is ending up with many indicators that make seeing the “wood from the trees” more difficult than it would otherwise be. Afterall, this important safety tool is intended to focus minds on the riskiest parts of an operation.


[1] ICAO Annex 19 – Safety Management. Appendix 2. Framework for a Safety Management System (SMS). 3. Safety assurance. 3.1 Safety performance monitoring and measurement.

Is Airworthiness Dead? 2/

Where I left the discussion there was a question mark. What does conformity mean when constant change is part of the way an aircraft system works?

It’s reasonable to say – that’s nothing new. Every time, I boot up this computer it will go through a series of states that can be different from any that it has been through before. Cumulative operating system updates are regularly installed. I depend on the configuration management practices of the Original Equipment Manufacturer (OEM). That’s the way it is with aviation too. The more safety critical the aircraft system the more rigorous the configuration management processes.

Here comes the – yes, but. Classical complex systems are open to verification and validation. They can be decomposed and reconstructed and shown to be in conformance with a specification.

Now, we are going beyond that situation where levels of complexity prohibit deconstruction. Often, we are stuck with viewing a system as a “black box[1]. This is because the internal workings of a system are opaque or “black.” This abstraction is not new. The treatment of engineered systems as black boxes dates from the 1960s. However, this has not been the approach used for safety critical systems. Conformity to an approved design remains at the core of our current safety processes. 

It’s as well to take an example to illustrate where a change in thinking is needed. In many ways the automotive industry is already wrestling with these issues. Hands free motoring means that a car takes over from a driver and act as a driver does. A vehicle may be semi or fully autonomous. Vehicles use image processing technologies that take vast amounts of data from multiple sensors and mix it up in a “black box” to arrive at the control outputs needed to safely drive.

Neural networking or heuristic algorithms may be the tools used to make sense of a vast amount of constantly changing real world data. The machine learns as it goes. As technology advances, particularly in machine learning ability, it becomes harder and harder to say that a vehicle system will always conform to an understandable set of rules. Although my example is automotive the same challenges are faced by aviation.

There’s a tendance to see such issues as over the horizon. They are not. Whereas the research, design and development communities are up to speed there are large parts of the aviation community that are not ready for a step beyond inspection and conformity checking in the time honoured way.

Yes, Airworthiness is alive and kicking. As a subject, it now must head into unfamiliar territory. Assumptions held and reinforced over decades must be revisited. Checking conformity to an approved design may no longer be sufficient to assure safety.

There are more questions than answers but a lot of smart people seeking answers.

POST 1: Explainability is going to be one of the answers – I’m sure. Explained: How to tell if artificial intelligence is working the way we want it to | MIT News | Massachusetts Institute of Technology

POST 2: Legislation, known as the Artificial Intelligence Act ‘Risks posed by AI are real’: EU moves to beat the algorithms that ruin lives | Artificial intelligence (AI) | The Guardian

POST 3: The world of the smart phone and the cockpit are here How HUE Shaped the Groundbreaking Honeywell Anthem Cockpit


[1] In science, computing, and engineering, a black box is a device, system, or object which produces useful information without revealing information about its internal workings.

Is Airworthiness dead?

Now, there’s a provocative proposition. Is Airworthiness dead? How you answer may depend somewhat on what you take to be the definition of airworthiness.

I think the place to start is the internationally agreed definition in the ICAO Annexes[1] and associated manuals[2]. Here “Airworthy” is defined as: The status of an aircraft, engine, propeller or part when it conforms to its approved design and is in a condition for safe operation.

Right away we start with a two-part definition. There’s a need for conformity and safety. Some might say that they are one and the same. That is, that conformity with an approved design equals safety. That statement always makes me uneasy given that, however hard we work, we know approved designs are not perfect, and can’t be perfect.

The connection between airworthiness and safety seems obvious. An aircraft deemed unsafe is unlikely to be considered airworthy. However, the caveat there is that centred around the degree of safety. Say, an aircraft maybe considered airworthy enough to make a ferry flight but not to carry passengers on that flight. Safety, that freedom from danger is a particular level of freedom.

At one end is that which is thought to be absolutely safe, and at the other end is a boundary beyond which an aircraft is unsafe. When evaluating what is designated as “unsafe” a whole set of detailed criteria are called into action[3].

Dictionaries often give a simpler definition of airworthiness as “fit to fly.” This is a common definition that is comforting and explainable. Anyone might ask: is a vehicle fit to make a journey through air or across sea[4] or land[5]? That is “fit” in the sense of providing an acceptable means of travel. Acceptable in terms of risk to the vehicle, and any person or cargo travelling or 3rd parties on route. In fact, “worthiness” itself is a question of suitability.

My provocative proposition isn’t aimed at the fundamental need for safety. The part of Airworthiness meaning in a condition for safe operation is universal and indisputable. The part that needs exploring is the part that equates of safety and conformity.

A great deal of my engineering career has been accepting the importance of configuration management[6]. Always ensuring that the intended configuration of systems, equipment or components is exactly what is need for a given activity or situation. Significant resources can be expended ensuing that the given configuration meets a defined specification.

The assumption has always been that once a marker has been set down and proven, then repeating a process will produce a good (safe) outcome. Reproducibility becomes fundamental. When dealing with physical products this works well. It’s the foundation of approved designs.

But what happens when the function and characteristics of a product change as it is used? For example, an expert system learns from experience. On day one, a given set of inputs may produce predicable outputs. On day one hundred, when subject to the same stimulus those outputs may have changed significantly. No longer do we experience steadfast repeatable.

So, what does conformity mean in such situations? There’s the crux of the matter.


[1] ICAO Annex 8, Airworthiness of Aircraft. ISBN 978-92-9231-518-4

[2] ICAO Doc 9760, Airworthiness Manual. ISBN 978-92-9265-135-0

[3] https://www.ecfr.gov/current/title-14/chapter-I/subchapter-C/part-39

[4] Seaworthiness: the fact that a ship is in a good enough condition to travel safely on the sea.

[5] Roadworthy: (of a vehicle) in good enough condition to be driven without danger.

[6] https://www.apm.org.uk/resources/what-is-project-management/what-is-configuration-management/

Safety Research

I’ve always found Patrick Hudson’s[1] graphic, that maps safety improvements to factors, like technology, systems, and culture an engaging summary. Unfortunately, it’s wrong or at least that’s my experience. I mean not wholly wrong but the reality of achieving safety performance improvement doesn’t look like this graph. Figure 1[2].

Yes, aviation safety improvement has been as story of continuous improvement, at least if the numbers are aggregated. Yes, a great number of the earlier improvements (1950s-70s) were made by what might be called hard technology improvements. Technical requirements mandated systems and equipment that had to meet higher performance specifications.

For the last two decades, the growth in support for safety management, and the use of risk assessment has made a considerable contribution to aviation safety. Now, safety culture is seen as part of a safety management system. It’s undeniably important[3].

My argument is that aviation’s complex mix of technology, systems, and culture is not of one superseding the other. This is particularly relevant in respect of safety research. Looking at Figure 1, it could be concluded that there’s not much to be gained by spending on technological solutions to problems because most of the issues rest with the human actors in the system. Again, not diminishing the contribution human error makes to accidents and incidents, the physical context within which errors occur is changing dramatically.

Let’s imagine the role of a sponsor of safety related research who has funds to distribute. For one, there are few such entities because most of the available funds go into making something happen in the first place. New products, aircraft, components, propulsion, or control systems always get the lion’s share of funds. Safety related research is way down the order.

The big aviation safety risks haven’t changed much in recent years, namely: controlled flight into terrain (CFIT), loss of control in-flight (LOC-I), mid-air collision (MAC), runway excursion (RE) and runway incursion (RI)[4]. What’s worth noting is that the potential for reducing each one of them is changing as the setting within which aviation operates is changing. Rapid technological innovation is shaping flight and ground operations. The balance between reliance on human activities and automation is changing. Integrated systems are getting more integrated.

As the contribution of human activities reduces so an appeal to culture has less impact. Future errors may be more machine errors rather than human errors.

It’s best to get back to designing in hard safety from day one. Safety related research should focus more on questions like; what does hard safety look like for high levels of automation, including use of artificial intelligence? What does hard safety look like for autonomous flight? What does hard safety look like for dense airspace at low level?

Just a thought.


[1] https://nl.linkedin.com/in/patrick-hudson-7221aa6

[2] Achieving a Safety Culture in Aviation (1999).

[3] https://www.flightsafetyaustralia.com/2017/08/safety-in-mind-hudsons-culture-ladder/

[4] https://www.icao.int/Meetings/a41/Documents/10004_en.pdf