We still don’t really know how bicycles work

Forget mysterious dark matter and the inexplicable accelerating expansion of the universe; the bicycle represents a far more embarrassing hole in the accomplishments of physics.

Let’s be honest, a bit of the pleasure at Chris Froome’s victory in the Tour de France is down to this being our second victory in a row and to the thought that the French haven’t won it since 1985. What must be worse for them, though, is that when it comes to the science of team cycling, even the Belgians are in front.
 
At the University of Mons, researchers are developing something called the Anaconda. It’s never going to be much of a speed machine because it is, in effect, a chain of monocycles with handlebars. These units are connected, by means of hinges that allow them to snake along, to a normal two-wheeled bike at the front. Every rider in the chain can be going in a slightly different direction, which means it takes an enormous amount of control and collaboration to move the thing forward. According to Olivier Verlinden, chief engineer on the project, the main qualification for riders is to be unafraid of falling off.
 
It’s fun, apparently. The idea is to unleash it as a beach-resort bike, the kind of thing that stag and hen parties will use to terrorise seaside towns across the world. But it is also scientifically interesting. Why? Because we still don’t really know how bicycles work.
 
It is rare that most people appreciate the bicycle, but it is quite an extraordinary machine. Push a riderless bike, letting it roll freely at high enough speeds, and it can withstand pushes from the side – it will wobble a little, but quickly recover. In the conventional analysis, that is because the gyroscopic force of the front wheel, its mass and the spontaneous turn of the handlebars all act together to keep the bicycle rolling forwards. This has something to do with the gyroscopic effect, the force that keeps a spinning top upright. You can feel this by removing a wheel from your pushbike and spinning it while you hold the axle spindles. If you try to change the orientation of the wheel, you’ll feel it push back against you.
 
The first mathematical analysis of bicycles suggested that this is also what keeps a moving bike on its wheels. But although the equations were written down in 1910, physicists always had nagging doubts about whether this was the whole story.
 
The most definitive analysis came exactly a century later. It involved an experimental bicycle that had all its gyroscopic effects cancelled out by a system of counter-rotating wheels. The effort of building such a strange contraption was worth it: the resulting paper was published the prestigious journal Science.
 
The publication plunged bicycle dynamics back into chaos. It turns out that taking into account the angles of the headset and the forks, the distribution of weight and the handlebar turn, the gyroscopic effects are not enough to keep a bike upright after all. What does? We simply don’t know. Forget mysterious dark matter and the inexplicable accelerating expansion of the universe; the bicycle represents a far more embarrassing hole in the accomplishments of physics.
 
And it may not be solved any time soon; very few researchers are working full-time on bicycle dynamics and there’s very little money in it. Once we’ve discovered exactly how these contraptions work, it might be possible to come up with bold new designs of bicycle – perhaps even better than the Anaconda. But nobody is desperate for that to happen; not even the French.
 
Maybe that’s OK. In an age where we have worked out the history of the cosmos and the secret of life, it’s rather nice that the humble bicycle keeps our feet on the ground. 
 
Cyclists during the Tour de France. Photo: Getty

Michael Brooks holds a PhD in quantum physics. He writes a weekly science column for the New Statesman, and his most recent book is At the Edge of Uncertainty: 11 Discoveries Taking Science by Surprise.

This article first appeared in the 29 July 2013 issue of the New Statesman, Summer Double Issue

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The Brexit Beartraps, #2: Could dropping out of the open skies agreement cancel your holiday?

Flying to Europe is about to get a lot more difficult.

So what is it this time, eh? Brexit is going to wipe out every banana planet on the entire planet? Brexit will get the Last Night of the Proms cancelled? Brexit will bring about World War Three?

To be honest, I think we’re pretty well covered already on that last score, but no, this week it’s nothing so terrifying. It’s just that Brexit might get your holiday cancelled.

What are you blithering about now?

Well, only if you want to holiday in Europe, I suppose. If you’re going to Blackpool you’ll be fine. Or Pakistan, according to some people...

You’re making this up.

I’m honestly not, though we can’t entirely rule out the possibility somebody is. Last month Michael O’Leary, the Ryanair boss who attracts headlines the way certain other things attract flies, warned that, “There is a real prospect... that there are going to be no flights between the UK and Europe for a period of weeks, months beyond March 2019... We will be cancelling people’s holidays for summer of 2019.”

He’s just trying to block Brexit, the bloody saboteur.

Well, yes, he’s been quite explicit about that, and says we should just ignore the referendum result. Honestly, he’s so Remainiac he makes me look like Dan Hannan.

But he’s not wrong that there are issues: please fasten your seatbelt, and brace yourself for some turbulence.

Not so long ago, aviation was a very national sort of a business: many of the big airports were owned by nation states, and the airline industry was dominated by the state-backed national flag carriers (British Airways, Air France and so on). Since governments set airline regulations too, that meant those airlines were given all sorts of competitive advantages in their own country, and pretty much everyone faced barriers to entry in others. 

The EU changed all that. Since 1994, the European Single Aviation Market (ESAM) has allowed free movement of people and cargo; established common rules over safety, security, the environment and so on; and ensured fair competition between European airlines. It also means that an AOC – an Air Operator Certificate, the bit of paper an airline needs to fly – from any European country would be enough to operate in all of them. 

Do we really need all these acronyms?

No, alas, we need more of them. There’s also ECAA, the European Common Aviation Area – that’s the area ESAM covers; basically, ESAM is the aviation bit of the single market, and ECAA the aviation bit of the European Economic Area, or EEA. Then there’s ESAA, the European Aviation Safety Agency, which regulates, well, you can probably guess what it regulates to be honest.

All this may sound a bit dry-

It is.

-it is a bit dry, yes. But it’s also the thing that made it much easier to travel around Europe. It made the European aviation industry much more competitive, which is where the whole cheap flights thing came from.

In a speech last December, Andrew Haines, the boss of Britain’s Civil Aviation Authority said that, since 2000, the number of destinations served from UK airports has doubled; since 1993, fares have dropped by a third. Which is brilliant.

Brexit, though, means we’re probably going to have to pull out of these arrangements.

Stop talking Britain down.

Don’t tell me, tell Brexit secretary David Davis. To monitor and enforce all these international agreements, you need an international court system. That’s the European Court of Justice, which ministers have repeatedly made clear that we’re leaving.

So: last March, when Davis was asked by a select committee whether the open skies system would persist, he replied: “One would presume that would not apply to us” – although he promised he’d fight for a successor, which is very reassuring. 

We can always holiday elsewhere. 

Perhaps you can – O’Leary also claimed (I’m still not making this up) that a senior Brexit minister had told him that lost European airline traffic could be made up for through a bilateral agreement with Pakistan. Which seems a bit optimistic to me, but what do I know.

Intercontinental flights are still likely to be more difficult, though. Since 2007, flights between Europe and the US have operated under a separate open skies agreement, and leaving the EU means we’re we’re about to fall out of that, too.  

Surely we’ll just revert to whatever rules there were before.

Apparently not. Airlines for America – a trade body for... well, you can probably guess that, too – has pointed out that, if we do, there are no historic rules to fall back on: there’s no aviation equivalent of the WTO.

The claim that flights are going to just stop is definitely a worst case scenario: in practice, we can probably negotiate a bunch of new agreements. But we’re already negotiating a lot of other things, and we’re on a deadline, so we’re tight for time.

In fact, we’re really tight for time. Airlines for America has also argued that – because so many tickets are sold a year or more in advance – airlines really need a new deal in place by March 2018, if they’re to have faith they can keep flying. So it’s asking for aviation to be prioritised in negotiations.

The only problem is, we can’t negotiate anything else until the EU decides we’ve made enough progress on the divorce bill and the rights of EU nationals. And the clock’s ticking.

This is just remoaning. Brexit will set us free.

A little bit, maybe. CAA’s Haines has also said he believes “talk of significant retrenchment is very much over-stated, and Brexit offers potential opportunities in other areas”. Falling out of Europe means falling out of European ownership rules, so itcould bring foreign capital into the UK aviation industry (assuming anyone still wants to invest, of course). It would also mean more flexibility on “slot rules”, by which airports have to hand out landing times, and which are I gather a source of some contention at the moment.

But Haines also pointed out that the UK has been one of the most influential contributors to European aviation regulations: leaving the European system will mean we lose that influence. And let’s not forget that it was European law that gave passengers the right to redress when things go wrong: if you’ve ever had a refund after long delays, you’ve got the EU to thank.

So: the planes may not stop flying. But the UK will have less influence over the future of aviation; passengers might have fewer consumer rights; and while it’s not clear that Brexit will mean vastly fewer flights, it’s hard to see how it will mean more, so between that and the slide in sterling, prices are likely to rise, too.

It’s not that Brexit is inevitably going to mean disaster. It’s just that it’ll take a lot of effort for very little obvious reward. Which is becoming something of a theme.

Still, we’ll be free of those bureaucrats at the ECJ, won’t be?

This’ll be a great comfort when we’re all holidaying in Grimsby.

Jonn Elledge edits the New Statesman's sister site CityMetric, and writes for the NS about subjects including politics, history and Brexit. You can find him on Twitter or Facebook.