A car’s handbrake is the lever to a completely mechanical braking system, which will bypass the primary hydraulic system if it fails. When the handbrake is applied, the brake cable passes through an intermediate lever, to increase the force of your pull; this force is then split evenly between your brakes by an equaliser.
Typically, a mechanical lever is added to the existing disc or drum brakes on the car. In drum brakes, the handbrake cable runs directly to a lever on the brake shoes. In disc brakes an additional lever and corkscrew is added to the existing calliper piston. When the handbrake is pulled, the lever forces the corkscrew against the piston, which would normally be activated by the hydraulic foot pedal system.
Although it is reassuring to have a secondary braking system for emergencies, the primary use of the handbrake tends to be when parking as they remain engaged until a release button is pressed; stopping your car potentially rolling away. This is good practise, as it keeps your brake cable from seizing up, ready for when you really need it. In fact, using your handbrake to stop a moving car can actually damage the brake system, so it is best to save this for real emergencies!

On board an aircraft carrier

Our article on how to take off and land on an aircraft carrier back in issue 5 was so popular we’ve gone a step further to bring you an insight to life on board the magnificent Nimitz Class carrier USS Abraham Lincoln. Discover what happens on this floating island – from the nuclear power at its heart to the aircraft stowed in the hangars and on the flightdeck.

Titan – the wonder of Saturn’s largest moon revealed

We take a look at the fascinating Titan and learn about the unusual activity that takes place on and below the surface of this, the most Earth-like of all the bodies in our solar system. A real eye-opener, this article explains the mystical methane rain that falls slowly through Titan’s dense atmosphere.

iPhone 4

Our cover feature comes complete with all you need to know about Apple’s latest smartphone. Read on to discover just what this anticipated update is capable of and follow our step-by-step guide to making your first FaceTime video call. We explain iOS4, the three-axis gyroscope and the A4 chip plus much more. And of course, all the gory insides are dissected for your viewing pleasure.

Cleaning up an oil spill

The headline-dominating disaster in the Gulf of Mexico has captured the attention of the world, and the grave situation has affected both the environment and the economy. Discover what is being done to seal the leak and clean up the mess in this feature that explores the techniques for ridding the world’s oceans of slicked oil.

Megastructures

Your jaw will drop when you consider the mammoth feats of engineering behind Earth’s biggest man-made structures. Learn how the longest bridge in the world was constructed, find out how the longest ever road tunnel beat the world record by seven kilometers, discover the pendulum swinging at the heart of the famous Taipai 101 skyscraper, plus loads more unbelievable megastructure facts.

King of the swingers

This bumper guide to our closest relatives reveals the lives and anatomy of the highly specialised and highly intelligent primates. See what happens when a group of chimps gives chase, learn about their amazing gripping hands and prehensile tails, and find out what is putting these incredible creatures at risk.

PLUS: today’s cutting-edge car technology, hangovers, baggage handling, adrenaline, in-flight refuelling, air bags, Facebook’s new privacy settings, blood vessels, the T-34 tank, mammoths, ion engines, dry cleaning, the Mars 500 mission, the Mavizen TTX02 electric superbike, air conditioning, IMAX cinemas, power drills, tree rings, starfish anatomy, the history of duelling, amphibian skin, beehives, Leyden jars, heatwaves, and much more besides.

Look out for How It Works issue 10 when it hits the shops 15 July – earlier if you’re a subscriber. And don’t forget, if you can’t get to the shops, you can also download the awesome PixelMag on your shiny new iPad, or your old iPhone or iPod touch. Just visit the Apple App Store and search for How It Works, then download any issue for just £1.79. Check it out today!

The Solar Impulse, an experimental aircraft that is powered solely from sunlight, has made its first ever 24-hour flight. Pilot André Borschberg eased the Solar Impulse aircraft on to the runway at Payerne airfield, about 31 miles south-west of the Swiss capital, Berne, at 9am local time today. The news comes as welcome relief for the dedicated team who have worked on the Impulse for over seven years and who recently had to delay the launch due to a malfunctioning part that needed to be replaced. It also brings the team one step closer to their ultimate goal of encircling the Earth purely by solar power.

For more information on the Solar Impulse refer to issue 7 of How It Works.

Don’t miss issue 9, which is packed full of articles to really feed your brain. Kicking off is an exhilarating four-pager on roller coasters and the science of thrills, and if you’re trying to decide between iPhone and Android, we’ve put them head to head in a useful buyer’s guide centred on how they work. Another close-to-home feature looks at superfast broadband and how new technology is capable of providing faster, more efficient internet services. An excellent feature on the nervous system reveals what keeps our bodies functioning and communicating properly, but if that doesn’t get your synapses firing we have another biology article that explains what heart bypass surgery entails. A mighty four-page article explaining the nature of explosives will keep you hooked while a hot and steamy spread on geysers will enlighten you on these spectacular geological features. Never get caught short during an avalanche as we explain what they are and how to survive them. If you want to learn how the most deadly chopper in the world works, check out our teardown of the Apache Longbow. Meanwhile, for information on the engineers attempting to break the land speed record take a look at our article on the race to 1,000mph. In space, we have a complete guide to Mercury, a look inside Jupiter’s moon Io, details about the Cassini-Huygens mission and how that’s working, plus a huge feature exploring our search for new Earth-like planets in the galaxy. Discover how the Greeks took to the seas and did battle in huge warships called Triremes, find out why the Tower of Pisa leans and how the west was won in our Wild West weapons article as well as a look at how the Battle of Britain was fought.

We also answer questions such as why can crocodiles snap their mouths so powerfully but not open them with the same force, how does bulletproof glass work, how do placebos work, what are allergies, how do hummingbirds beat their wings up to 80 times a second, how is it possible to rain frogs, how do volcanoes work, what is a Wankel engine, and what are solar flares?

So don’t miss out, get your copy of How It Works issue 9, available in all good newsagents and supermarkets. And if you want to enjoy the magazine on your iPad, iPhone, or iPod touch, simply visit the Apple App Store and search for How It Works, then download it for just £1.79. Check it out today!

Superfast broadband

So, we all rely on broadband for our insatiable internet habits, and as with many things in life, we’re also demanding a faster, more efficient service. In this month’s cover feature you’ll learn how broadband speeds are being maximised. You can also find out what superfast broadband can be used for, and with the help of some very snazzy infographics discover the cities currently enjoying the fastest services around the world.

Human nervous system

Another electrifying human science article this issue comes in the form of a complete guide to the human nervous system. The feature reveals the nature of our bodies’ built-in autopilot functions, as well as the anatomy of a nerve and the reason behind why our arm tingles if we knock our funny bone.

Volcanic eruptions

Thousands of air passengers around the world were left stranded or unable to travel due to the ash from an Icelandic volcano. Discover the amazing geography of these sleeping geological giants in our massive volcanoes feature.

The world’s deadliest chopper

Take a look inside the AH-64D Apache Longbow, the next generation of multi-mission attack helicopter that’s changing the face of modern warfare. We dissect the vehicle and explain its components in true How It Works style.

The race to 1,000mph

Three teams of world-class engineers from different corners of the globe – Great Britain, the United States and Australia – are all trying to smash the 1,000mph barrier and break the land speed record with their superfast rocket cars. We get under the hood of each vehicle and discover exactly how they will achieve their high-speed dreams.

Searching for new Earths

Focusing far beyond the solar system, this space special takes a look at how we’re searching for Earth-like planets capable of supporting human life. Discover the incredible techniques space agencies are employing to find extrasolar bodies, as well as info on where we’re focusing our search, not to mention the exciting results of recent missions.

There’s oodles more great stuff to discover this issue, including how the Battle of Britain was fought, why hummingbirds can beat their wings so quickly, the causes allergies, how a heart bypass could save your life, what a spark plug does exactly, an explanation of solar flares, why the Tower of Pisa leans, the difference between fog, mist and haze, what’s inside a worm, the reason crocodiles can snap their jaws shut with great power but can’t open them with the same force, causes of avalanches, a complete guide to the planet Mercury, inside a Greek warship and so much more great stuff that we simply can’t be bothered to list.

Look out for How It Works issue 9 when it hits the shops this Thursday, 17 June – earlier if you’re a subscriber. And don’t forget, if you can’t get to the shops, you can also download the awesome PixelMag on your shiny new iPad, or your old iPhone or iPod Touch. Just visit the Apple App Store and search for How It Works, then download any issue for just £1.79. Check it out today!

From the performance-enhancing technology of the World Cup to the most unashamed luxury available on the planet’s most expensive mega yachts, this issue will keep you distracted long after you were supposed to get back to work. But don’t feel guilty; read on and feed your brain with fascinating facts on the wonder of twins, exploring below the surface of the oceans, creating the real Iron Man and the technologies capable of augmenting human abilities, surviving Mount Everest, how the Dyson bladeless fan works, the projects of the European Space Agency, Petra the city built into the rock, the first commercial jet pack, and much more. You can also get to know Simon Reeve in this month’s Global Eye interview. His Tropic Of Cancer TV series has been wowing audiences as he embraces some of the planet’s least-visited locations, mixing spectacular travel destinations with eye-opening current affairs.

An issue not to be missed.

So don’t miss out, get your copy of How It Works issue 8, available in all good newsagents and supermarkets. And if you want to enjoy the magazine on your iPad, iPhone, or iPod touch, simply visit the Apple App Store and search for How It Works, then download it for just £1.79. Check it out today!

First up is this month’s rather swanky cover feature: Mega Yachts. You won’t believe the high technology and advanced design of these masters of the seas. In this four-page extravaganza we look at the biggest and best the yachting industry has to offer, and we even knocked up a little brainstorm of what our ideal mega yacht might look like – just for fun like.

To keep you bang up to date with the greatest technology in the world, we thought you might enjoy this in-depth look at the World Cup and the amazing new tech behind this, the grandest of football tournaments. Discover everything you need to know about the stadium, its security, the seating, the pitch, even the kits and boots and the high-end materials used.

For all you star gazers out there this lovely infographic in the Space section reveals the various types of star out there. If you don’t know your brown dwarfs from your hypernovae you should check this out.

Intrepid fans of the most spectacular landscapes Earth has to offer will enjoy soaking up every word of this guide to surviving the world’s tallest  mountain: Everest (or Chomolungma as it’s known in Tibet). From the camps to the training and the risks, this feature will give you a clear idea of what to expect of this mammoth human challenge.

The ultimate in personal flight, the Martin Jetpack is the world’s first commercial personal flying machine. Before you get your chequebook out, however, take a look at this article that explains exactly how it gets off the ground. We even managed to grab a few minutes with the engineers and designers.

One of life’s little miracles, the wonder of twins and multiple births is always a talking point. This great science feature explains just why this quite unbelievable medical phenomena occurs. We also slotted in a few fascinating facts – it’s uncanny, it really is!

Making the real Iron Man is the subject of this next science feature. From the most incredible developments in synthetic organ augmentation to some of the most advanced exoskeletal machines assisting humans in their daily work, this feature reveals how science can enhance our abilities and make us almost superhuman.

Issue 8 is of course rammed with loads more essential features for you to get your face into. Some of the highlights include a huge feature about exploring beneath the waves, the science behind why the volcanic ash cloud grounded hundreds of flights in Europe, the Nexus One smartphone from Google, a complete guide to the European Space Agency, Uranus explained, Dyson’s amazing bladeless fan, electric cigarettes, toasters, the Taj Mahal, the Coriolis effect, moles (the skin kind), mirrors, sunburn, crash-test dummies, G-force, the seasons, bird migration, hot-air balloons, afterburners, why feet smell, pinball tables, Sky Player, windmills, and the city of Petra. There’s loads more, but we’ll let you discover it for yourself when you pick the mag up on Thursday 20 May – or even earlier if you’re a subscriber!

The latest edition of How It Works is not to be missed. We really don’t know where to start as there’s so much crammed in this month. As well as our exclusive interview with Professor Brian Cox, we also have hundreds of fine facts to feast on. Here are the highlights: inside the iPad, emergency vehicles, petrol pumps, hydrogen-powered cars, dolphins, quicksand, coral reefs, optical illusions, space-exploring robots, human muscles, smoke alarms, Neptune, Spitzer Space Telescope, dialysis machines, superchargers, Medieval armour, fruit machines, hieroglyphs and much much more.

Our regular explainers from the Science Museum were also on-hand to answer all your crazy questions so do keep ’em coming. The news section features the Hubble Telescope, which celebrates its 20th birthday this Saturday (along with dep ed Helen – except she’s been 20 for nearly a decade), and the new UK Space Agency making its home in Oxford.

Issue 7 is a vintage issue that you’d be foolish to miss out on. How It Works is available in all good newsagents and supermarkets. And if you want to enjoy the magazine on your iPad, iPhone, or iPod Touch, simply visit the Apple App Store and search for How It Works, then download it for just £1.79. Check it out today!

Enjoy the issue…

We thought we’d start off by taking a look at emergency service vehicles. In the event of a disaster, the emergency services are always on hand to sort things out. From cop cars with high-tech tracking equipment to ambulances kitted out exactly like a hospital on wheels, you’ll learn everything you ever wanted to know about these life-saving vehicles in this bumper six-page feature.

With the launch of the iPad, we thought we’d open one up and take a look inside. Don’t worry, it’s not as gory as all that. In this clinical dissection you’ll see exactly what’s inside the iPad and discover how it works too.

We bring you yet another great space extravaganza this issue as we take an in-depth look at some of space exploration’s most amazing gizmos – space robots. Find out why developments in space robotics are so vital to the future of exploring our Solar System, and learn all about the robots of tomorrow in this four-page feature.

We asked our resident alternative fuel expert, HydroKevin, to set to work on a huge feature that ventures beneath the hood of hydrogen-powered cars and reveals just how these zero-emission vehicles work. Fully annotated and wonderfully explained, this feature is your one-stop shop for the answers to all your hydrogen-powered car questions.

And finally, because you keep telling us how much you all love discovering things you didn’t know about your own bodies, we thought it was about time we found out more about muscles – just how the dickens do they work? You’ll find out what muscles are made of, how an arm can flex as well as an insight to what affects muscle strength.

Of course, that’s not all. We also have plenty of nutritious edutainment on such essential subjects as smoke alarms, quicksand, coral reefs, fermentation, medieval armour, superchargers, Neptune, the Solar Impulse, dolphins, petrol pumps, rebreathers, brown dwarfs, the Spitzer Space Telescope, coal mining, vocal cords, fruit machines, understanding hieroglyphs and shed loads more. So as you can see, it’s all right here in issue 7 of How It Works – on sale 22 April and even earlier if you’re a subscriber. Enjoy the preview.

When the aircraft is standing still, the pressure in each tube is equal and the airspeed indicator shows zero. The rush of air in flight causes a pressure differential between the static tube and the pitot tube. The pressure differential makes the pointer on the airspeed indicator move. An increase of airspeed leads to the pressure at the end of the pitot tube raising.

In turn, the air pressure pushes against a diaphragm that moves a connected mechanical pointer on the face of the indicator (the gauge in the cockpit). The indicator is calibrated to compensate for winds in the air using electronic read-outs from the air and the ground. This system also compensates for altitude and air temperature to make the airspeed measurement accurate.