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
John Vincent 