Some may feel that the future of supersonic aviation is about as rosy, as an empty glass of tap water.
But!
A flight across the Atlantic in three-and-a-half hours, as is promised by the Boom Overture, is below the four-hour travel limit, where average people start to get anxious about being banged up!
Not for nothing do UK train companies want to get London and Edinburgh services below, the magic four-hour time.
Technology will get better to reduce the noise and carbon emissions of all aircraft and not just supersonic ones!
I don’t put it outside the genius of engineers to by 2050, be able to create a supersonic, almost noise-free aircraft.
These are comparisons of the Boom Overture to Concorde.
Engines – Three as opposed to four.
Length – Similar
Wingspan – 71 % of Concorde
Passengers – 75 % of Concorde
It’s almost as if the Boom Overture is a three-quarter scale model of Concorde.
The Wing/Airframe
When I left Liverpool University in 1968, I wasn’t totally sure, what I wanted to do. So I visited a lot of engineering and aerospace companies including both BAC and Hawker Siddeley. Including my own University, I must have visited about four or five large wind tunnels in that period and every one had a Concorde-like model for the wind tunnel.
Every company had their own ideas on what a supersonic wing, should look like.
And surprise-surprise they were all very similar!
Take the advertising off Formula One cars and paint them all silver and very few could tell them apart.
Aerodynamics defines the shape so strongly, they all look the same.
It’s the same with supersonic aircraft and I’m not surprised that wing planform of the Boom Overture appears to be similar to Concorde, but narrower.
Perhaps the more dart-like shape significantly reduces the drag? It should be noted that drag is proportional to cross-sectional area.
In Concorde’s Wikipedia entry there is a section called Development, which explains how the Royal Aircraft Establishment developed the slender delta wing planform, used by Concorde and now likely to be used by Boom.
Although, it would be different inside the wing, as Concorde was mainly made from metal and the Overture is a composite aircraft.
Perhaps composite construction helps with creating the perfect aerodynamic shape. I don’t have any experience of composites, but they surely mean more aerodynamic shapes and they are regularly used for airframes.
I suspect that Concorde was a nightmare to build, but that the challenge helped develop a large number of machining and fabrication techniques.
The Fuselage
As I said earlier, the length of the plane is similar to Concorde, but the wingspan is 29 % smaller and the number of passengers is around 25 % less.
But if you look at the picture of the aircraft in the Times article, where it is emerging from the hangar, it’s almost as if the fuselage has a square cross section than Concorde.
I wonder about this square cross section. I remember an interview on the radio with Barnes Wallis, where he talked about his latest idea for a fast supersonic aircraft capable of flying between the UK and Australia.
This paragraph is from Barnes Wallis’s Wikipedia entry.
In the late 1950s, Wallis gave a lecture entitled “The strength of England” at Eton College, and continued to deliver versions of the talk into the early 1970s, presenting technology and automation as a way to restore Britain’s dominance. He advocated nuclear-powered cargo submarines as a means of making Britain immune to future embargoes, and to make it a global trading power. He complained of the loss of aircraft design to the US, and suggested that Britain could dominate air travel by developing a small supersonic airliner capable of short take-off and landing.
It sounds to me that he would have been a Brexiteer.
Could this supersonic airliner, be what I heard him talking about?
I distinctly remember that he was advocating a fuselage with a square cross section for supersonic flight.
It would have given more space inside for passengers.
Concorde was a bit pokey with small windows!
The picture in The Times of the interior of the Boom Overture is certainly spacious.
Have Boom, been looking through Barnes Wallis’s ideas?
One quote I heard Barnes Wallis say, in an interview with Chris Brasher was this.
There is no greater thrill in life, than proving something is impossible and then showing how it can be done.
Boom may not have been able to develop a small supersonic airliner capable of short take-off and landing, but it does sound, they’ve developed a smaller supersonic airliner capable of shorter take-off and landing.
The Engines
In the Boom Overture’s Wikipedia entry there is a section called Engines, where this is the last sentence.
In July 2020, the company announced that it had entered into an agreement with Rolls-Royce to collaborate on engine development.
As Rolls-Royce built the engines for Concorde, they probably have some experience locked away.
The engines were fitted with afterburners, as the extra thrust was needed for take-off.
According to Wikipedia the engines had a high thermal efficiency in supersonic cruise.
According to Wikipedia, there was an engine without afterburning for a longer range Concorde under development.
Over the years, there have been various proposals for supersonic aircraft, in military, commercial and business fields, so I suspect Rolls-Royce have done significant work in powering supersonic flight.
But then other engine companies would have gone down similar routes!
Rolls-Royce though probably have all the data on the engine ideas for Concorde that failed.
I wouldn’t be surprised, if one of the major aero-engine companies has a solution to the powerplant for the Boom Overture, based on the chase for supersonic speeds forty and fifty years ago.
But Rolls-Royce because of the Concorde experience could be closer to a successful development.
So I think signing with Rolls-Royce could be a very sensible move.
The Afterburners
The Wikipedia entry for the Boom Overture says this about afterburners.
Boom wants to use moderate bypass turbofans without afterburners, unlike Concorde’s Rolls-Royce/Snecma Olympus.
Could that be one piece of complication, that improvements in technology has eliminated?
The Engine Intakes
The Wikipedia entry for the Olympus 593 engines has a section called Intakes.
They were thought to be clever in the 1960s, but they just look complicated to me, with all my extra experience.
The intakes seem to have used very comprehensive digital control systems, but these days controls like these will be even more comprehensive and a lot more sophisticated, as computing has moved on.
I very much feel that if the Boom Overture needed sophisticated variable-geometry engine intakes like Concorde, we have the knowledge to create them and the computer expertise to make them act as needed.
The Exhaust Nozzle
The Wikipedia entry for the Olympus 593 engines has a section called Exhaust Nozzle.
These too are complicated and a lot of what I said for the intakes, would apply to the nozzles.
The Fuel
The Wikipedia entry for the Boom Overture says
The aircraft is intended to run on Sustainable Aviation Fuel.
It is likely, that Sustainable Aviation Fuel will be used for commercial aviation until there is a significant move to hydrogen.
In the UK, a company called Altalto is building a large plant to make the fuel at Immingham from household and industrial waste.
One idea being pursued by some companies is to create the fuel from used disposable nappies.
Wikipedia indicates that the fuel could cut CO2 emissions by between 20-98%.
Altalto is backed by British Airways and Velocys, who are a spin-out from Oxford University.
There is certainly a lot of money and technology being thrown behind Sustainable Aviation Fuel to make it a net-zero alternative for the powering of aircraft.
The Noise
This Youtube video shows Concorde’s last take-off from New York.
It was certainly a noisy aircraft.
Concorde’s engines had afterburners.
It also needed a long take-off run, so it made more noise on the ground.
It used to take off with a high angle of attack with the nose high.
All of these factors would have increased real and perceived noise levels.
I feel that if the Boom Overture is going to have significantly lower noise levels than Concorde, then its design will need to be radically different.
The lack of afterburners will make some difference.
It carries only about 75 % of the passengers of Concorde.
It is roughly, the same length as Concorde, but the wingspan is nearly thirty percent smaller.
It looks like Alstom’s hydrogen-powered Class 600 train will not be ready for COP26.
But I suspect that the French would not like to be upstaged by a rolling stock leasing company and a university on the one hand and a company with scrapyard-ready redundant London Underground trains on the other.
I think, they could still turn up with something different.
They could drag one of their Coradia iLint trains through the Channel Tunnel and even run it to Scotland under hydrogen power, to demonstrate the range of a hydrogen-powered train.
Alstom have recently acquired Bombardier’s train interests in the UK and there have been rumours of a fleet of battery-electric Electrostars, even since the demonstrator ran successfully in 2015. Will the prototype turn up at COP26?
Alstom’s UK train factory is in Widnes and I’ve worked with Liverpudlians and Merseysiders on urgent projects and I wouldn’t rule out the Class 600 train making an appearance.
CAF
Spanish train company; CAF, have impressed me with the speed, they have setup their factory in Newport and have delivered a total of well over a hundred Class 195 and Class 331 trains to Northern.
I wrote Northern’s Battery Plans, in February 2020, which talked about adding a fourth-car to three-car Class 331 trains, to create a battery-electric Class 331 train.
Will the Spanish bring their first battery-electric Class 331 train to Glasgow?
I think, they just might!
After all, is there a better place for a train manufacturer looking to sell zero-carbon trains around the world to announce, their latest product?
Hitachi
A lot of what I have said for Alstom and CAF, could be said for Hitachi.
Hitachi have announced plans for two battery-electric trains; a Regional Battery Train and an Intercity Tri-Mode Battery Train.
I doubt that either of these trains could be ready for COP26.
But last week, I saw the new Hitachi Class 803 train speeding through Oakleigh Park station.
This is not a battery-electric train, where battery power can be used for traction, but according to Wikipedia and other sources, it is certainly an electric train fitted with batteries to provide hotel power for the train, when the overhead electrification fails.
Are these Class 803 trains already fitted with their batteries? And if they are, have they been tested?
And who is building the batteries for the Class 803 trains?
The traction batteries for Hitachi’s two battery-electric trains are to be produced by Hyperdrive Innovation of Sunderland, which is not far from Hitachi’s train factory at Newton Aycliffe.
As an engineer, I would suspect that a well-respected company like Hyperdrive Innovation, can design a battery-pack that plugs in to Hitachi’s trains, as a diesel engine would. I would also suspect that a good design, would allow an appropriate size of battery for the application and route.
I feel it is very likely, that all batteries for Hitachi’s UK trains will be designed and build by Hyperdrive Innovation.
If that is the case and the Class 803 trains are fitted with batteries, then Hitachi can be testing the battery systems.
This document on the Hitachi Rail web site, which is entitled Development of Class 800/801 High-speed Rolling Stock for UK Intercity Express Programme, gives a very comprehensive description of the electrical and computer systems of the Hitachi trains.
As an engineer and a computer programmer, I believe that if Hyperdrive Innovation get their battery design right and after a full test program, that Hitachi could be able to run battery-electric trains based on the various Class 80x trains.
It could be a more difficult task to fit batteries to Scotland’s Class 385 trains, as they are not fitted with diesel engines in any application. Although, the fitting of diesel engines may be possible in the global specification for the train.
It is likely that these trains could form the basis of the Regional Battery Train, which is described in this infographic.
Note.
The Class 385 and Regional Battery trains are both 100 mph trains.
Class 385 and Class 80x trains are all members of Hitachi’s A-Train family.
Regional Battery trains could handle a lot of unelectrified routes in Scotland.
I wouldn’t be surprised to see Hitachi bring a battery-equipped train to COP26, if the Class 803 trains have a successful introduction into service.
Siemens
Siemens have no orders to build new trains for the national rail network in the UK.
But there are plans by Porterbrook and possibly other rolling stock leasing companies and train operators to convert some redundant Siemens-built trains, like Class 350 trains, into battery-electric trains.
According to Wikipedia, Siemens upgraded East Midlands Railways, Class 360 trains to 110 mph operation, at their Kings Heath Depot in Northampton.
Could Siemens be updating one of the Class 350 trains, that are serviced at that depot, to a prototype battery-electric Class 350 train?
Stadler
Stadler have a proven design for diesel-electric, battery-electric and hydrogen trains, that they sell all over the world.
In the UK, the only ones in service are Greater Anglia’s Class 755 trains, which are diesel-electric bi-mode trains.
The picture shows one of these trains at Ipswich.
They are 100 mph trains.
Diesel, battery or hydrogen modules can be inserted in the short PowerPack car in the middle of the train.
Diesel-battery-electric versions of these trains have been sold for operation in Wales.
The interiors of these trains are designed for both short journeys and a two-hour run.
This article on Rail Advent is entitled COP26 To Showcase Britain’s Sustainable Trains Of The Future Thanks To Network Rail And Porterbrook Partnership.
The article talks about and shows pictures of Porterbrook’s HydroFLEX or Class 799 train, which has been developed by the University of Birmingham, fitted out for COP26.
I have downloaded this picture of the interior from Network Rail’s media centre.
But then some Class 319 trains used by commuters don’t look their age of over thirty years.
These pictures were taken on the Abbey Line in 2018.
There’s also this BBC Profile and video of the technology behind the HydroFLEX train.
Conclusion
It looks like Network Rail and Porterbrook are doing their best to showcase the best that Britain and Scotland can offer.
I am reminded of a tale, that I heard from a former GEC manager.
He was involved in selling one of GEC’s Air Traffic Control radars to a Middle Eastern country.
The only working installation of the radar was at Prestwick in Scotland, so he arranged that the dignitaries and the sales team would be flown to Prestwick in GEC’s HS 125 business jet.
As they disembarked at Prestwick and walked to the terminal, the pilot called the GEC Manager over.
The pilot told him “The Scottish Highlands at this time of the year, are one of the most beautiful places in the world! Would you and your guests like a low-level tour on the way back? I can arrange it, if you say so!”
Despite knowing GEC’s draconian attitude to cost control he said yes.
The sale was clinched!
Are Network Rail, Porterbrook, the UK and Scottish Governments, setting up the same Scottish treatment to all the delegates to COP26?
What this blog will eventually be about I do not know.
But it will be about how I’m coping with the loss of my wife and son to cancer in recent years and how I manage with being a coeliac and recovering from a stroke. It will be about travel, sport, engineering, food, art, computers, large projects and London, that are some of the passions that fill my life.
And hopefully, it will get rid of the lonely times, from which I still suffer.
The Anonymous Widower 