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👩‍✈️On the menu

There was no way of getting around the news about American Airlines last month. The airline placed an order for up to twenty, with an option for sixty, supersonic commercial aircraft from Boom. A Denver, Colorado, based start-up called. And that after United Airlines already put down an order for 15 aircraft. This issue will analyse the chances of succes for this new supersonic venture.

• Starter: Remember the Concorde?

• Main course: Will this be the next chapter in supersonic aviation?

• Desert: Getting rid of the sonic boom

🍜Starter

Remember the Concorde?

Of course you do. It was the world's first ever supersonic passenger aircraft. Developed by the British Aircraft Corporation and Sud Aviation from France. 20 aircraft where produced of which 6 where for non-commercial purposes. The design and the Mach 2 speed were ground breaking. Flying eighty passengers from New York to London in less than three hours was record breaking.

However, that speed came with a price. A very high price. In the 1970's a round trip ticket London - New York would cost $12.000 which in today's money is about $50.000. In that price range you have to compete with private jets.

And the ticket prices weren't the only problem. The operational opportunities of the aircraft were very limited because of the noise it made. Like all supersonic aircraft, the Concorde created a 'sonic boom'. A thunder-like noise that is produced repeatedly throughout the flight and can be heard from the ground. After several studies, leading to tens of thousands of noise complains, the Federal Aviation Administration (FAA) decided in 1973 that it was forbidden for civil flights to fly supersonic overland. Many other countries followed. This made it only possible to fly supersonic to and from coastal areas which limits the added value of the aircraft severely. It didn't take long before the Concorde would only fly between Paris, London and New York.

To what extend the crash of flight AF4590 influenced retiring the aircraft in 2003 is difficult to say. Even before 2000 is was no secret that the Concorde wasn't a commercially viable product. That crash probably gave it its last push.

🍲 Main course

Will this be the next chapter in supersonic aviation?

Now, nearly two decades after saying the Concorde farewell, the company Boom is developing the Overture. An aircraft that is supposed to fly Mach 1.7 with a range of 4.250 nautical mile (or 7871 kilometers) and 65 to 80 passengers on board. Being able to fly at such a high speed for so many miles sounds too good to be true. And when something sounds too good to be true, then it usually is.

You can be enthused by an entrepreneur who wants to revolutionize aviation and even gets two major airlines to tag along. Or you can look forward to seeing an aircraft as good looking as the Concorde once did at your local airport.

However, when you dive into Boom's plans it is difficult to be optimistic about their chances of success. And here is why:

Before take-off

Before any Boom aircraft can take off on a commercial flight, there are a couple of problems that need to be solved.

First off, there is no engine. Boom has been able to design a good looking airframe, but there is no sign of a power plant. Boom and Rolls Royce (the manufacturer of the Concorde engines) agreed to look into a new engine design in 2020. However, that collaboration ended last week. If the new aircraft would have been a regular passenger jet there would have been many options already available on the market. It would still take years to fully integrate the engine and the airframe, but the foundation would be there. The engines on the Concorde where specifically designed by Rolls Royce to fit that aircraft. Boom will need the same tailor made solution which is very expensive and will take years of development.

One requirement for the engine that has been published is that it needs to be able to fully run on Sustainable Aviation Fuel (SAF). This type of fuel produces much less carbon dioxide and is thus considered to be much more sustainable than regular aviation fuel. Boom wants to use SAF to cover for the immense fuel consumption and pollution that supersonic aircraft suffer from.

SAF is used in aviation at the moment, but only in small amounts. This is because it is not yet possible to produce it in large amounts and it is around 2,5 times more expensive than regular kerosene. IATA experts state that in 2025 about 2% of the total amount of required fuel can be produced as SAF. And even if SAF would be easily available and cheap, regulations prevent airlines from using more than 50% of SAF per flight due to technical restrictions. Companies like Airbus, GE, Bell and Safran are experimenting with flying on 100% SAF. Yet, the first commercial flight based on this type of fuel won't be here anytime soon.

The last hurdle to take before take-off is certification. Experts expect Boom to have difficulties with this as well. First, certification agencies like the FAA and EASA do not have much experience certifying supersonic aircraft that run on SAF. So it will take them a while to set up the proper certification requirements. Secondly, Boom hasn't got experience in certification processes at all. Even experienced companies like Boeing and Airbus have certification issues every now and then. Delaying the delivery of their aircraft by months or even years. Boom will definitely hire experts that are well versed in aircraft certifications. However, with so many novelties in one aircraft, it is difficult to project smooth sailing.

It is named after its biggest problem

Let's say that Boom will overcome the earlier mentioned problems and that it will be able to manufacture and certify the supersonic Overture. It will still have to overcome its major problem, the one thing it is named after: the supersonic boom.

As mentioned with the Concorde, due to legal restrictions, it was practically only possible to fly supersonic above an ocean. This won't be any different for the Overture.

Below are three maps that show the range of the Boom Overture from New York (JFK), Beijing (PEK) and London (LHR). Boom states that they aim for a range of 4250 nautical mile. The maps project a range of 3825 nautical mile, which is 10% less. This is because due to ATC-restrictions or weather, it is difficult for aircraft to reach their maximum range.

For the aircraft to be economically profitable it needs to pair large cities with enough residents that are willing to pay a high price to cut a few hours off their flight time. And because of the boom, there cannot be much land between the two airports or else the Overture won't be able to fly supersonic.

Looking at the maps you'll see that there are few city-pairs available. It will be possible to fly from the east coast of the USA and Canada to Europe. London or Paris to New York for example, like the Concorde did. From eastern Asia, an area with a lot of potential costumers, it is not possible to reach major cities in the USA and Canada (due to a lack of range) or Europe (because the entire flight would be overland). Flights between Beijing, Tokyo and Seoul will be too short for the Overture to make a difference.

So looking at the economics based on the range and the operational limitations of the supersonic boom, the possible routes will be comparable with the ones that the Concorde flew. Without much profit. 

So the Boom Overture will probably not be the next chapter in supersonic aviation. Mainly because it is not able to overcome the problems that lead to the end of the Concorde. Especially the supersonic boom, what the company is named after, is a hurdle that will be too big to overcome.

🍦 Desert

Getting rid of the sonic boom

Will it ever be possible to fly supersonic without the boom?

It isn't possible yet, but NASA is currently working on achieving this revolutionary step. Together with Lockheed-Martin, NASA is building an aircraft that is so aerodynamically shaped that its sonic boom is a lot less loud than with current supersonic aircraft. Watch this video if you want to know more about the project, how a sonic boom is created and the future of supersonic aviation.

You made it to the end! 👏

Thank you for reading this third issue of Airline Food for Thought. If you have any questions or suggestions you can contact me via [email protected] or send me a message via LinkedIn.For more about me, visit giel.io