0:00:03 > 0:00:07# There are lots of things all around us
0:00:07 > 0:00:10# Exciting things that surround us
0:00:10 > 0:00:13- #- But how does it work?- Do you know?
0:00:13 > 0:00:17- #- How is it made?- Do you know?
0:00:17 > 0:00:20# Things that go up Things that go down
0:00:20 > 0:00:23# Things that go pop Things that go round
0:00:23 > 0:00:27# With special cameras to show you inside
0:00:27 > 0:00:30# It's going to be a big surprise
0:00:30 > 0:00:33- #- But how does it work?- Do you know?
0:00:33 > 0:00:37- #- How is it made?- Do you know?
0:00:37 > 0:00:40- # Do you know?- Let's find out!- #
0:00:45 > 0:00:51Hello, I'm Maddie and today I've come to see a very exciting vehicle.
0:00:51 > 0:00:53See if you can guess what it is.
0:00:53 > 0:00:57It carries people in it, it doesn't have wings and it
0:00:57 > 0:01:01has a big piece of metal on top that spins round and round.
0:01:01 > 0:01:03Can you guess what it is?
0:01:03 > 0:01:07OK, I'll give you one more clue. It sounds like this.
0:01:07 > 0:01:10ROTOR BLADES WHIR
0:01:12 > 0:01:15That's right, it's a helicopter.
0:01:15 > 0:01:16Noisy, isn't it?
0:01:18 > 0:01:20Helicopters are amazing to watch.
0:01:20 > 0:01:23Have you ever seen one flying in the sky?
0:01:23 > 0:01:26You often hear them before you see them.
0:01:32 > 0:01:35This bit of the helicopter is called a landing skid,
0:01:35 > 0:01:37and there are two of them.
0:01:37 > 0:01:39They're the helicopter's feet.
0:01:42 > 0:01:46This bit at the front is where the pilot sits to fly the helicopter.
0:01:46 > 0:01:48It's called the cockpit.
0:01:48 > 0:01:52And then this long part at the back of the helicopter is called
0:01:52 > 0:01:56the tail boom and at the end of it is the tail rotor.
0:01:56 > 0:01:59This spins round and round when the helicopter flies,
0:01:59 > 0:02:01just like the big rotor at the top.
0:02:01 > 0:02:04This big rotor is really important
0:02:04 > 0:02:06because it helps make the helicopter fly.
0:02:06 > 0:02:11But do you know how a helicopter rotor works?
0:02:11 > 0:02:12Let's find out.
0:02:18 > 0:02:21To get a closer look at the rotor at the top of the helicopter,
0:02:21 > 0:02:25I'm going to use my special camera. So here we go,
0:02:25 > 0:02:27let's move it right to the top.
0:02:27 > 0:02:29This part in the middle,
0:02:29 > 0:02:33that is called the rotor disc, and then these two long metal things
0:02:33 > 0:02:37coming out of the sides are called the rotor blades.
0:02:37 > 0:02:38Let's move along.
0:02:40 > 0:02:44They are so long, aren't they?
0:02:44 > 0:02:48But can you see that one edge of the rotor blade
0:02:48 > 0:02:50is slightly thinner than the other?
0:02:50 > 0:02:53I think it looks a bit like a fish, don't you?
0:02:53 > 0:02:58But let's move back to the middle now to look at the rotor disc.
0:02:58 > 0:03:01Oh, the rotor disc has lots of metal parts, doesn't it?
0:03:01 > 0:03:04So to understand how it really works
0:03:04 > 0:03:06we need to look in more detail.
0:03:07 > 0:03:10On top of the helicopter is the rotor.
0:03:10 > 0:03:14The long blades meet in the centre and are attached to
0:03:14 > 0:03:17a metal pole called the rotor mast.
0:03:17 > 0:03:21When the helicopter engine starts, the rotor mast starts to spin
0:03:21 > 0:03:24round and round, making the blades spin too.
0:03:24 > 0:03:29Another circle of metal called the swash plate also spins round.
0:03:29 > 0:03:35It's attached to the blades by two metal poles called control rods.
0:03:35 > 0:03:40These rods are connected to controls inside the helicopter cockpit.
0:03:40 > 0:03:45To make the helicopter take off, the pilot moves a lever upwards.
0:03:45 > 0:03:51This moves the control rods in the rotor, which makes the blades move.
0:03:51 > 0:03:54When the blades are in the right position, they push the
0:03:54 > 0:03:59air downwards, and this allows the helicopter to lift up into the air.
0:03:59 > 0:04:03The pilot pushes another lever to make the rotor tilt
0:04:03 > 0:04:07up at the back, and this makes the helicopter go forwards.
0:04:07 > 0:04:10To go backwards, the pilot pulls the lever back,
0:04:10 > 0:04:12which tips the rotor up at the front,
0:04:12 > 0:04:16so the helicopter goes backwards.
0:04:16 > 0:04:17Clever, isn't it?
0:04:17 > 0:04:21Shall we see the rotor working on this helicopter?
0:04:21 > 0:04:25But, before we fly, the pilot and I need to put our headsets on.
0:04:25 > 0:04:27And I'm going to be talking through this.
0:04:27 > 0:04:32It's called a microphone, and it might make my voice sound funny.
0:04:32 > 0:04:35I think we're ready to go.
0:04:35 > 0:04:37ENGINE REVS UP
0:04:37 > 0:04:40Watch the blades start to turn.
0:04:42 > 0:04:45Slowly at first
0:04:45 > 0:04:49and then very, very fast.
0:04:51 > 0:04:54We're just warming the engine up now but
0:04:54 > 0:04:57when we're ready, Tom's going to pull the lever,
0:04:57 > 0:05:00which will move the blades into the right position,
0:05:00 > 0:05:04and when we're catching the air, we'll take off.
0:05:04 > 0:05:07RADIO CHATTERS
0:05:07 > 0:05:09Here we go.
0:05:13 > 0:05:15Wow!
0:05:20 > 0:05:24You can see Tom the pilot now is using the cyclic lever
0:05:24 > 0:05:26to tilt the rotor up at the back,
0:05:26 > 0:05:29and this makes the helicopter go forwards.
0:05:33 > 0:05:35Wow, we're so high!
0:05:42 > 0:05:45The view is beautiful from up here.
0:05:47 > 0:05:52Now we're heading to a town. The houses look tiny.
0:05:52 > 0:05:55They look like doll's houses.
0:05:55 > 0:05:57We're coming in to land now.
0:05:59 > 0:06:01And there we go, we're back at base.
0:06:01 > 0:06:04What was your favourite bit about finding out
0:06:04 > 0:06:06how helicopter rotors work?
0:06:06 > 0:06:10Do you remember the name of the long pieces of metal that turn
0:06:10 > 0:06:11to make the helicopter fly?
0:06:11 > 0:06:14That's right, they're called the rotor blades.
0:06:14 > 0:06:17Did you hear the sound the helicopter made
0:06:17 > 0:06:19when I was standing near it?
0:06:19 > 0:06:22ROTOR BLADES WHIR Noisy, isn't it?
0:06:22 > 0:06:25And did you see the way the helicopter travelled forwards
0:06:25 > 0:06:28when the pilot moved the lever inside the cockpit?
0:06:33 > 0:06:36So, now you know how the rotor on top of a helicopter works
0:06:36 > 0:06:39and how it makes a helicopter fly.
0:06:39 > 0:06:43Helicopters are exciting vehicles, aren't they?
0:06:43 > 0:06:45They're fun to watch in the air,
0:06:45 > 0:06:48but not many people travel around in helicopters.
0:06:48 > 0:06:51But there are lots of other vehicles, aren't there?
0:06:51 > 0:06:54And you might have had a go on some of them.
0:06:54 > 0:06:56You might have been on a bicycle
0:06:56 > 0:07:01or a scooter, or maybe a tricycle.
0:07:01 > 0:07:04Have you ever ridden a tricycle?
0:07:04 > 0:07:06Tricycles are great fun.
0:07:06 > 0:07:07They're a bit like bicycles,
0:07:07 > 0:07:10except they have three wheels instead of two,
0:07:10 > 0:07:14and that helps you to balance.
0:07:14 > 0:07:15Off I go.
0:07:16 > 0:07:20But do you know how a tricycle is made?
0:07:20 > 0:07:21Let's find out.
0:07:28 > 0:07:32To see how a tricycle is made, I've come here.
0:07:32 > 0:07:37Inside that workshop they make lots of tricycles,
0:07:37 > 0:07:40some for grown-ups and some for children.
0:07:40 > 0:07:42Let's go see how one's made.
0:07:48 > 0:07:52To make a tricycle, first the mechanics open up this box,
0:07:52 > 0:07:56and can you believe that all the parts needed
0:07:56 > 0:07:58to build one tricycle fit inside?
0:07:58 > 0:08:00Over to you, Scott.
0:08:00 > 0:08:03There are 25 parts to this tricycle
0:08:03 > 0:08:06and they're all different shapes and sizes.
0:08:06 > 0:08:10Can you guess what some of them are going to be?
0:08:10 > 0:08:13This is one of the pedals,
0:08:13 > 0:08:17the part you push with your feet to turn the wheels.
0:08:17 > 0:08:19And what about this?
0:08:19 > 0:08:25Well, these are the handlebars, the bit you hold with your hands.
0:08:25 > 0:08:28And what about this one?
0:08:28 > 0:08:33This is called the saddle, and it's the bit you sit on.
0:08:33 > 0:08:35Now all the pieces are out of the box,
0:08:35 > 0:08:37Scott can start making the tricycle.
0:08:37 > 0:08:42First he puts two big red pieces of metal on to a stand.
0:08:42 > 0:08:44The metal pieces are called the frame,
0:08:44 > 0:08:46and he attaches them together.
0:08:46 > 0:08:50Scott hangs them up on the stand because it makes it easier
0:08:50 > 0:08:52to attach all the other pieces.
0:08:52 > 0:08:55It's like it's floating in mid-air.
0:08:56 > 0:08:58On goes the saddle.
0:08:59 > 0:09:02Next, Scott is going to put the chain on.
0:09:02 > 0:09:06The chain is a big loop of metal links that help the pedals
0:09:06 > 0:09:08turn the wheels, but this can be fiddly,
0:09:08 > 0:09:13so I'm going to put a special camera on Scott's head.
0:09:13 > 0:09:14OK.
0:09:14 > 0:09:18By attaching the camera to Scott's head, we're going to be able
0:09:18 > 0:09:22to see what he sees when he's putting the bike chain on.
0:09:22 > 0:09:25- Does that feel comfortable? - Yep, it's fine.- OK, on you go.
0:09:25 > 0:09:29Now we're getting a really clear view of everything Scott is seeing.
0:09:29 > 0:09:33First, he's picked up the chain and looped it around
0:09:33 > 0:09:35that metal circle. It's called the cog.
0:09:38 > 0:09:42Scott joins the chain together using a chain tool.
0:09:42 > 0:09:45He adjusts the frame of the bike using a spanner
0:09:45 > 0:09:47to make sure the chain is tight.
0:09:47 > 0:09:51Then he tests it to make sure the chain fits perfectly
0:09:51 > 0:09:52and won't fall off.
0:09:53 > 0:09:56Now the chain is fixed in place,
0:09:56 > 0:10:01the next part of the tricycle to go on are these - they're pedals.
0:10:01 > 0:10:05You push the pedals with your feet to turn the chain,
0:10:05 > 0:10:07which moves the tricycle.
0:10:07 > 0:10:10There are still quite a few pieces left, aren't there?
0:10:10 > 0:10:13Well, now we need the front mudguard.
0:10:19 > 0:10:21A back mudguard.
0:10:25 > 0:10:27The other back mudguard.
0:10:32 > 0:10:33Back basket.
0:10:39 > 0:10:42And the front basket.
0:10:47 > 0:10:50Now it's time for the front wheel,
0:10:50 > 0:10:54and it's attached to the frame with these big bolts.
0:10:58 > 0:11:00TING TING! Nyoooooom!
0:11:00 > 0:11:04Well, you can't have a tricycle without handlebars,
0:11:04 > 0:11:08and these ones are great because they've got a bell on them.
0:11:08 > 0:11:10Listen to this sound. TING TING!
0:11:10 > 0:11:12Let's hear it again. TING TING!
0:11:12 > 0:11:13Isn't that fun?
0:11:13 > 0:11:15Here you go, Scott.
0:11:17 > 0:11:21To attach the handlebars, Scott is using a special tool.
0:11:21 > 0:11:23It's called an Allen key,
0:11:23 > 0:11:26and you might have seen a grown-up using one at home.
0:11:26 > 0:11:28It has a shape at the end of it.
0:11:28 > 0:11:30Do you know what this is?
0:11:30 > 0:11:34This shape is a hexagon and it has six sides.
0:11:34 > 0:11:37This fits into a bolt at the top of the handlebars and,
0:11:37 > 0:11:41as Scott twists it, it makes sure they're on really tight.
0:11:43 > 0:11:47Next, Scott attaches the brakes and cables.
0:11:47 > 0:11:52Brakes are really important because we need them to stop the tricycle.
0:11:52 > 0:11:55This bit here is called the brake lever,
0:11:55 > 0:12:00and when we squeeze it this cable pulls these bits of rubber
0:12:00 > 0:12:05on to the wheel, which slows it down and brings it to a stop, like this.
0:12:05 > 0:12:10Having started with all those pieces, we've got just two left,
0:12:10 > 0:12:12the back wheels.
0:12:18 > 0:12:23The back wheels are attached to the tricycle and it's ready to go.
0:12:26 > 0:12:29Ha, and here is the finished tricycle.
0:12:29 > 0:12:30What do you think?
0:12:30 > 0:12:33It looks fantastic, doesn't it?
0:12:33 > 0:12:37But sometimes the mechanics here add a few extra bits
0:12:37 > 0:12:41so that children with disabilities can use the tricycles too.
0:12:41 > 0:12:44BELLS RING
0:12:44 > 0:12:47These pedals have extra straps to help keep your feet in the
0:12:47 > 0:12:52right place, and this saddle has a comfy backrest and a seatbelt.
0:12:52 > 0:12:56This is great for someone who needs a bit of extra help sitting up.
0:12:56 > 0:12:59And this is a handle so that a grown-up
0:12:59 > 0:13:01can help push somebody along.
0:13:02 > 0:13:06What was your favourite bit about seeing how a tricycle was made?
0:13:06 > 0:13:10Do you remember what you call the special tool Scott used
0:13:10 > 0:13:12to tighten the bolts on the handlebars?
0:13:12 > 0:13:15That's right, it's an Allen key.
0:13:15 > 0:13:18Did you hear the sound the bell made when I pressed it?
0:13:18 > 0:13:20TING TING! Isn't that fun?
0:13:20 > 0:13:24And did you see all the different parts of the tricycle
0:13:24 > 0:13:26when they were unpacked from the big box?
0:13:32 > 0:13:36So the next time you see a tricycle, or get to ride on one yourself,
0:13:36 > 0:13:39you know just how it's made.
0:13:39 > 0:13:42And now you know how a helicopter rotor works,
0:13:42 > 0:13:45just like on this one here.
0:13:45 > 0:13:47I'll see you next time.
0:13:47 > 0:13:48BYE!
0:13:55 > 0:13:58# There are lots of things All around us
0:13:58 > 0:14:02# Exciting things that surround us
0:14:02 > 0:14:05- #- But how does it work?- Do you know?
0:14:05 > 0:14:08- #- How is it made?- Do you know?
0:14:08 > 0:14:12- # Do you know?- Let's find out!- #