0:00:22 > 0:00:25Buried deep within this ship is a piece of technology that has
0:00:25 > 0:00:27transformed the modern world.
0:00:27 > 0:00:31We're about to fire up one of the biggest engines in the world!
0:00:31 > 0:00:33Here it goes!
0:00:33 > 0:00:36MEHANICAL WHIRRING Incredible!
0:00:36 > 0:00:40That same technology is also in this train...
0:00:40 > 0:00:41TRAIN HORN HONKS
0:00:41 > 0:00:42HE LAUGHS
0:00:42 > 0:00:45..this lorry,
0:00:45 > 0:00:46this submarine...
0:00:46 > 0:00:49You feel like you're in an engine walking through here.
0:00:49 > 0:00:50..and this tractor.
0:00:53 > 0:00:56I'm talking about the diesel engine.
0:00:56 > 0:00:58Now, some may think the diesel
0:00:58 > 0:01:02is what powers their sensible family car.
0:01:02 > 0:01:06Well, I'm here to tell you that it's much, much more than that.
0:01:07 > 0:01:12No other engine is so versatile or used in so many applications.
0:01:12 > 0:01:14Oh, my God, it's genius, I love it.
0:01:14 > 0:01:18The vast majority of the world's commercial, industrial,
0:01:18 > 0:01:23agricultural, mining and military vehicles are powered by diesel.
0:01:23 > 0:01:25Bring on the diesels!
0:01:25 > 0:01:27Yeah!
0:01:27 > 0:01:29My name is Mark Evans
0:01:29 > 0:01:33and this is a story I've been wanting to tell for a long time.
0:01:33 > 0:01:36I've had a lifelong love affair with diesels
0:01:36 > 0:01:40ever since I learned to drive tractors on the farm as a lad.
0:01:40 > 0:01:42Even to this day...
0:01:42 > 0:01:43HE SNIFFS
0:01:43 > 0:01:47..if I catch that heady whiff of diesel,
0:01:47 > 0:01:49it brings back very happy memories.
0:01:50 > 0:01:52Lovely!
0:01:52 > 0:01:57This is the unlikely tale of how a 19th-century invention became
0:01:57 > 0:02:00the 21st century's most important engine.
0:02:00 > 0:02:02It's massive, it's everywhere, it's everything you do.
0:02:02 > 0:02:07Engines like these are the unsung workhorse of the modern world!
0:02:07 > 0:02:08ALARM BLARES
0:02:08 > 0:02:10There are alarms going off everywhere!
0:02:21 > 0:02:26The story of the diesel engine starts with a man and a mystery.
0:02:28 > 0:02:35In 1913, a body was discovered in the North Sea by a Dutch steam ship.
0:02:37 > 0:02:43Documents on the corpse revealed it to be a German man
0:02:43 > 0:02:47who'd disappeared ten days earlier on a ferry
0:02:47 > 0:02:50travelling between Antwerp and London.
0:02:50 > 0:02:56His name was Rudolf Diesel and just years before,
0:02:56 > 0:03:02he had invented the most efficient heat engine the world had ever seen.
0:03:03 > 0:03:06He was rich, famous,
0:03:06 > 0:03:09a friend to the great American inventor Thomas Edison.
0:03:10 > 0:03:17So why would such a gifted, successful man
0:03:17 > 0:03:21throw himself off a ferry?
0:03:23 > 0:03:27The answer, for me, lies in the engine he created.
0:03:29 > 0:03:35The diesel was patented in Germany in 1892.
0:03:35 > 0:03:36It was one of several new engines
0:03:36 > 0:03:39being developed in the late 19th century
0:03:39 > 0:03:42to replace the ageing steam engine.
0:03:43 > 0:03:48Steam power had run the factories, mills, trains and ships
0:03:48 > 0:03:50that had driven the industrial era.
0:03:50 > 0:03:54But steam engines were bulky, labour-intensive
0:03:54 > 0:03:56and very inefficient.
0:03:57 > 0:04:01For engineers like Diesel, the route to a replacement for steam
0:04:01 > 0:04:05lay in a recent technological breakthrough,
0:04:05 > 0:04:09a technology this museum in West Wales is dedicated to -
0:04:09 > 0:04:11internal combustion.
0:04:11 > 0:04:13- Mark, how are you?- Hi.
0:04:13 > 0:04:17'Here, curator Paul Evans has assembled an incredible collection
0:04:17 > 0:04:21'of the internal combustion engines that were vying to replace steam.'
0:04:23 > 0:04:27Steam engines had used external combustion, meaning the fuel, coal,
0:04:27 > 0:04:32was burned in a separate chamber to the engine itself.
0:04:32 > 0:04:35The new internal combustion engines aimed to be more efficient,
0:04:35 > 0:04:38by burning their fuel inside the engine.
0:04:40 > 0:04:44But there was something different about the one I'm here to see.
0:04:44 > 0:04:48Its method of internal combustion would make it
0:04:48 > 0:04:52the most important engine in the modern world and this is it -
0:04:52 > 0:04:57the only functioning example in Britain of an original diesel.
0:04:57 > 0:05:01- There she is.- Look at that. And the only one that's working?
0:05:01 > 0:05:03She's the only running in the UK.
0:05:03 > 0:05:05Probably the oldest running in the world, we think.
0:05:05 > 0:05:09Can we get a bit closer and kind of touch and smell this thing?
0:05:09 > 0:05:14'This model is the same design Diesel first demonstrated in 1897
0:05:14 > 0:05:17'while working for a German machineworks.'
0:05:17 > 0:05:20It's an extraordinary piece of kit.
0:05:20 > 0:05:21Just...
0:05:21 > 0:05:23Just gorgeous.
0:05:23 > 0:05:26The immediate advantage internal combustion engines
0:05:26 > 0:05:32like the diesel had over steam was they only needed one man to operate.
0:05:32 > 0:05:35So, listen, how do you start it?
0:05:43 > 0:05:45- Nice, I bet that tastes good. - 1998.
0:05:45 > 0:05:46MARK CHUCKLES
0:05:46 > 0:05:49WHIRRING
0:05:50 > 0:05:52AIR HISSES
0:05:52 > 0:05:54It's like coming alive.
0:05:56 > 0:05:58Just lovely! Ah!
0:05:59 > 0:06:03Incredible! This is such a treat.
0:06:03 > 0:06:07Compare that to what was before this, the steam engine.
0:06:07 > 0:06:10Firing up a steam engine took so many people,
0:06:10 > 0:06:12it was a right old fiasco
0:06:12 > 0:06:15getting them started and keeping them running.
0:06:15 > 0:06:18One man gets this engine running in a few minutes.
0:06:18 > 0:06:21But what made Diesel's engine unique
0:06:21 > 0:06:24compared to other internal combustion machines
0:06:24 > 0:06:28was the way it burned the fuel inside its cylinder -
0:06:28 > 0:06:31a process called compression ignition,
0:06:31 > 0:06:34something Diesel found inspiration for
0:06:34 > 0:06:39in a type of pneumatic cigar lighter, popular in the late 19th century.
0:06:39 > 0:06:42- It's a bicycle pump with no outlet, isn't it?- Yeah.
0:06:42 > 0:06:46Essentially, so if you put it down here, so you've got the bottom here,
0:06:46 > 0:06:49you'd have some tinder, and just a plunger piston.
0:06:49 > 0:06:52So, let's see what happens when I push the plunger.
0:06:55 > 0:06:56And look at that, you get fire.
0:06:56 > 0:07:01That is the simple secret behind every diesel engine
0:07:01 > 0:07:02that has ever been made.
0:07:02 > 0:07:08If you compress air far enough, it gets hot enough to start a fire.
0:07:10 > 0:07:12It's so simple, that's the beauty of it.
0:07:12 > 0:07:13You take air, you compress it,
0:07:13 > 0:07:15the more you compress it, the hotter it gets.
0:07:15 > 0:07:18If you compress it enough,
0:07:18 > 0:07:20when you squirt some fuel in it, that fuel will burn.
0:07:20 > 0:07:24The expanding gas then pushes the piston down again. Dead simple.
0:07:24 > 0:07:27What compression ignition gave Diesel's engine
0:07:27 > 0:07:32was unparalleled efficiency which completely eclipsed steam power.
0:07:33 > 0:07:37Steam engines were, at best, 10% efficient.
0:07:38 > 0:07:41In Diesel's invention, 30% of the energy
0:07:41 > 0:07:43was converted to useful power,
0:07:43 > 0:07:46more than any other internal combustion engine.
0:07:46 > 0:07:52In fact, it was the most efficient engine the world had ever seen.
0:07:52 > 0:07:55You're talking about an engine that's three times as efficient,
0:07:55 > 0:08:00so a third of the cost to run it. It's a huge thing.
0:08:00 > 0:08:04- Three times more efficient? - Nearly four.
0:08:04 > 0:08:08Wow. This was a seismic shift...
0:08:08 > 0:08:12- Yeah.- ..in terms of how you powered our world.
0:08:13 > 0:08:17In the 1900s, internal combustion engines, like the diesel,
0:08:17 > 0:08:21started replacing steam engines in mills and factories
0:08:21 > 0:08:24across the industrial world.
0:08:24 > 0:08:27Diesel's first designs ran on peanut oil
0:08:27 > 0:08:32but soon the standard fuel became a form of crude oil.
0:08:32 > 0:08:36His design was licensed internationally and he made
0:08:36 > 0:08:41a small fortune, but Diesel had higher hopes for his invention.
0:08:41 > 0:08:46He was a utopian thinker who published books on social reform.
0:08:46 > 0:08:50He believed his engine could release workers from wage slavery
0:08:50 > 0:08:53and break corporate monopolies.
0:08:53 > 0:08:59He wrote of his hopes that his machine would change the world.
0:08:59 > 0:09:03But the gap between Diesel's ambitions for his engine
0:09:03 > 0:09:06and the grubby realities of business soon widened.
0:09:06 > 0:09:09Just because he was a brilliant engineer didn't make him
0:09:09 > 0:09:15a brilliant businessman and as a result of battles about patents
0:09:15 > 0:09:17and some poor business decisions,
0:09:17 > 0:09:21he saw his wealth quite literally slip through his fingers.
0:09:21 > 0:09:25By the time he stepped aboard the ferry in September 1913,
0:09:25 > 0:09:30he had already lost 10 million Deutsche Marks.
0:09:30 > 0:09:33Was that the reason he threw himself overboard?
0:09:34 > 0:09:35Maybe.
0:09:35 > 0:09:37But I have a feeling it wasn't just
0:09:37 > 0:09:41because he was losing control of his wealth,
0:09:41 > 0:09:46but because he was losing control of the destiny of his invention.
0:09:49 > 0:09:53Rudolf Diesel, the pacifist and utopian thinker,
0:09:53 > 0:09:58had become distraught by a new application of his invention,
0:09:58 > 0:10:01an application that was going to change the face
0:10:01 > 0:10:07of 20th-century warfare - the world's first-ever stealth weapon,
0:10:07 > 0:10:08the submarine.
0:10:11 > 0:10:17Exactly what drove Rudolf Diesel to suicide will perhaps never be known.
0:10:19 > 0:10:23But what is certain is the submarine would be a turning point
0:10:23 > 0:10:27in the development of the diesel engine.
0:10:27 > 0:10:31As war approached in 1913, European nations had been
0:10:31 > 0:10:36striving for decades to perfect submarine technology.
0:10:36 > 0:10:38The problem was how to power them.
0:10:39 > 0:10:42Steam engines were totally impractical.
0:10:43 > 0:10:47The internal combustion engine seemed to be the solution.
0:10:47 > 0:10:49The only question was
0:10:49 > 0:10:54whether that would mean Diesel's engine or one of its competitors.
0:10:54 > 0:10:58Diesel's compression ignition engine was one of two
0:10:58 > 0:11:01major types of internal combustion engine being developed.
0:11:01 > 0:11:04The other was this, the petrol engine.
0:11:04 > 0:11:08The petrol and diesel engines functioned in very similar ways,
0:11:08 > 0:11:10save one key aspect.
0:11:10 > 0:11:13The fundamental difference between a diesel
0:11:13 > 0:11:18and a petrol engine is the way you start the fire inside them.
0:11:18 > 0:11:23Whereas the diesel engine ignites fuel by compressing air,
0:11:23 > 0:11:24the petrol engine ignites
0:11:24 > 0:11:28with electrically-produced sparks from a spark plug.
0:11:30 > 0:11:34Spark ignition helped give the petrol engine a crucial advantage
0:11:34 > 0:11:38over the diesel - it produced a more powerful combustion.
0:11:40 > 0:11:45So, when the Royal Navy commissioned this, its first-ever submarine,
0:11:45 > 0:11:48the vessel was equipped with a petrol engine.
0:11:48 > 0:11:52The Royal Navy's top brass believed that the superior power
0:11:52 > 0:11:56and performance of the early petrol engines would be the key to finally
0:11:56 > 0:12:03making a submersible warship possible but trials soon proved them wrong.
0:12:03 > 0:12:06And the reason these petrol submarines were about to run
0:12:06 > 0:12:11into trouble lay in the engine's spark ignition system.
0:12:11 > 0:12:15For a spark ignition engine like a petrol engine to work,
0:12:15 > 0:12:18it needs a fuel that's flammable, it'll burn, but it's also volatile.
0:12:18 > 0:12:20And you can demonstrate the difference between diesel
0:12:20 > 0:12:22and petrol very easily, but I'm just going to try
0:12:22 > 0:12:25and light the diesel in this container here.
0:12:29 > 0:12:33And it goes out straightaway because that will burn
0:12:33 > 0:12:35but it's less refined
0:12:35 > 0:12:38so it won't set on fire just by putting a match in it.
0:12:38 > 0:12:40Compare that with petrol.
0:12:46 > 0:12:48And there you have the difference -
0:12:48 > 0:12:51petrol is volatile, even at room temperature, it lets off fumes,
0:12:51 > 0:12:56that's why you can smell it so easily and the vapour is flammable.
0:12:56 > 0:12:58That is a very dangerous fuel to be around.
0:13:00 > 0:13:05Early petrol engines leaked flammable fuel and fumes from every pore,
0:13:05 > 0:13:09which made the Navy's petrol submarines so prone to fire
0:13:09 > 0:13:12that white mice were kept onboard.
0:13:12 > 0:13:16If the mice became overwhelmed by petrol fumes, then the crew
0:13:16 > 0:13:19knew it might be a good idea to shut the engines down
0:13:19 > 0:13:22and open a porthole which...
0:13:22 > 0:13:25is easier said than done...
0:13:25 > 0:13:27in one of these.
0:13:28 > 0:13:32You can get a sense of what being stuck next to a petrol engine
0:13:32 > 0:13:37in a submerged tin can was like by starting one up...
0:13:37 > 0:13:39Ignition on. Here we go, wish us luck.
0:13:42 > 0:13:47..which with a 100-year-old engine is no picnic.
0:13:47 > 0:13:49Happy your end?
0:13:52 > 0:13:54I'm not at the right point, am I?
0:13:54 > 0:13:56If you get it set in the right place...
0:13:56 > 0:13:57What? Do you think I'm too near me?
0:13:57 > 0:13:59'I guess this is what you get
0:13:59 > 0:14:01'when you try starting up a petrol engine
0:14:01 > 0:14:03'in a documentary about the diesel.'
0:14:05 > 0:14:08- Not enough effort. - Is that what it is? No, tell me.
0:14:08 > 0:14:09Literally, more effort needed.
0:14:11 > 0:14:12HE GROANS
0:14:12 > 0:14:15When did they invent the starter motor?
0:14:18 > 0:14:19ENGINE WHIRS
0:14:19 > 0:14:20Yes!
0:14:20 > 0:14:22Finally!
0:14:24 > 0:14:25Oh, my God, I'm knackered!
0:14:27 > 0:14:29What a beast!
0:14:30 > 0:14:35There is petrol literally dripping and oozing out of this engine.
0:14:35 > 0:14:40Would you want to be in a submarine powered by one of these?
0:14:43 > 0:14:47While the Royal Navy persisted with petrol-powered submarines,
0:14:47 > 0:14:49the French and Germans were experimenting
0:14:49 > 0:14:52with diesel-powered subs.
0:14:52 > 0:14:55Diesel oil wasn't prone to fire like petrol
0:14:55 > 0:14:59and the diesel engine's remarkable efficiency
0:14:59 > 0:15:03gave the submarine something the petrol engine could not -
0:15:03 > 0:15:04its most vital attribute,
0:15:04 > 0:15:09the range to reach the enemy's vulnerable shipping lanes.
0:15:10 > 0:15:14Britain would eventually commission its own diesel submarines
0:15:14 > 0:15:16like this one, HMS Alliance.
0:15:17 > 0:15:23Charlie Haywood and Leo Hubbard both worked on vessels such as these.
0:15:23 > 0:15:25Charlie, Leo, I've never been in a submarine before
0:15:25 > 0:15:29and you feel like you're in an engine walking through here.
0:15:29 > 0:15:30Yes, they called me Piston.
0:15:30 > 0:15:32THEY CHUCKLE
0:15:32 > 0:15:35So, you, Charlie, you were a crew onboard.
0:15:35 > 0:15:38On HMS Artful which is identical to this, basically,
0:15:38 > 0:15:41and so I would have been on my first submarine
0:15:41 > 0:15:45as Chief of the Watch in the engine room here.
0:15:45 > 0:15:48How much of your life did you spend essentially living right next
0:15:48 > 0:15:49to big diesel engines?
0:15:49 > 0:15:52Eh, probably about...
0:15:53 > 0:15:57- ..ten years.- So, ten years of your life, literally, feet from...
0:15:57 > 0:16:01- Well, I used to go to shore sometimes.- Did you?
0:16:01 > 0:16:02- They let you ashore?- Yes.
0:16:02 > 0:16:06- So, yeah.- So you must have quite a love affair with these things?
0:16:06 > 0:16:09I wouldn't say that, I have a respect, a healthy respect.
0:16:09 > 0:16:12They can go wrong very quickly if you don't look after them.
0:16:12 > 0:16:15HMS Alliance was designed for service in the vast expanse
0:16:15 > 0:16:20of the Pacific during the Second World War,
0:16:20 > 0:16:24which is where the diesel engine's 30% fuel efficiency
0:16:24 > 0:16:26became invaluable.
0:16:26 > 0:16:30The petrol engine had efficiency of around 12%,
0:16:30 > 0:16:32less than half of the diesel.
0:16:32 > 0:16:34This meant, for the same volume of fuel,
0:16:34 > 0:16:39a diesel submarine could travel much further than a petrol vessel.
0:16:39 > 0:16:43How important was the distance you could travel in a submarine?
0:16:43 > 0:16:44The range was important.
0:16:44 > 0:16:46By the time you got on patrol, it'd be time to come back
0:16:46 > 0:16:48if you didn't have a long range.
0:16:48 > 0:16:51How long a range? How far could you go?
0:16:51 > 0:16:5410,500 miles before you'd need to refuel,
0:16:54 > 0:16:59on the surface at an economical cruising speed of 11 knots.
0:16:59 > 0:17:02- 10,500... - 10,500 nautical...
0:17:02 > 0:17:05- That's a very long way.- Yeah.
0:17:05 > 0:17:07Would you have ever achieved that on a petrol engine
0:17:07 > 0:17:11- in terms of efficiency? - No.- No.- Couldn't.
0:17:11 > 0:17:12Absolutely impossible.
0:17:12 > 0:17:15No, you wouldn't and you wouldn't be able to store enough fuel.
0:17:15 > 0:17:20The First World War was the submarine's proving ground.
0:17:20 > 0:17:26The Royal Navy's first petrol-powered submarines had a range of 280 miles.
0:17:26 > 0:17:30By the end of the war, the Germans were building diesel U-boats
0:17:30 > 0:17:34with a range of over 11,000 miles.
0:17:34 > 0:17:36With sufficient range to attack Allied shipping
0:17:36 > 0:17:43in the Atlantic, Germany's submarines sank over 5,000 ships.
0:17:43 > 0:17:47The diesel had won its first battle against the petrol engine.
0:17:49 > 0:17:52The diesel engine gave the submarine the range,
0:17:52 > 0:17:57safety and reliability it needed to become one of the iconic weapons
0:17:57 > 0:17:58of the 20th century,
0:17:58 > 0:18:02not a use that Rudolf Diesel would have wanted for his invention.
0:18:02 > 0:18:06But the submarine also gave the diesel engine something,
0:18:06 > 0:18:08a unique application,
0:18:08 > 0:18:11a proving ground for its unique properties
0:18:11 > 0:18:14and properties that, after the First World War,
0:18:14 > 0:18:17would be in greater demand than ever before.
0:18:19 > 0:18:22Despite the diesel engine's success in submarines,
0:18:22 > 0:18:28the rest of the First World War was a victory for the petrol engine.
0:18:28 > 0:18:32Most of the conflict's new vehicle developments were petrol-powered -
0:18:32 > 0:18:35aircraft, tanks, trucks.
0:18:36 > 0:18:40The diesel engine was too big, too heavy and too slow-running
0:18:40 > 0:18:43to be of use in these new technologies
0:18:43 > 0:18:48so when peace time saw an explosion in mass-produced road transport,
0:18:48 > 0:18:52these vehicles were almost all petrol-powered too.
0:18:53 > 0:18:54By the late 1920s,
0:18:54 > 0:18:59there didn't seem to be a future for the diesel engine in road vehicles
0:18:59 > 0:19:03but in the early 1930s, that was all about to change
0:19:03 > 0:19:07as a result of one of the greatest untold stories
0:19:07 > 0:19:10in the history of British engineering
0:19:10 > 0:19:14and the key to that story is under the bonnet of this -
0:19:14 > 0:19:18the Citroen Rosalie, built in 1934,
0:19:18 > 0:19:24and the first commercially available diesel car the world had ever seen.
0:19:24 > 0:19:25CAR HORN HONKS
0:19:27 > 0:19:30What a beautiful car!
0:19:31 > 0:19:36Now, buried deep inside here is one of the most important
0:19:36 > 0:19:41technological innovations in the history of the diesel engine.
0:19:41 > 0:19:44It's this, a Comet swirl chamber.
0:19:44 > 0:19:48Now, it looks pretty unassuming, doesn't it, but it had
0:19:48 > 0:19:53a seismic impact on the story of diesel-powered road transport.
0:19:55 > 0:20:00The Comet swirl chamber was the key to making diesel engines small enough
0:20:00 > 0:20:04yet still powerful enough to be used in road vehicles.
0:20:04 > 0:20:08It was the brainchild of the man who established this cutting-edge
0:20:08 > 0:20:11engine development company, Harry Ricardo.
0:20:12 > 0:20:15Harry Ricardo was born in 1885
0:20:15 > 0:20:19and designed his first engine as a schoolboy.
0:20:19 > 0:20:22During the war, he developed engines for tanks
0:20:22 > 0:20:26and used the profits to build his company.
0:20:26 > 0:20:30In the 1920s, Harry set about cracking the puzzle of making
0:20:30 > 0:20:33diesel engines usable in road vehicles.
0:20:34 > 0:20:37For ex-Ricardo engineer Dave Morrison,
0:20:37 > 0:20:41who worked with Harry, it was a passion for efficiency
0:20:41 > 0:20:44that drove Ricardo towards diesel technology.
0:20:44 > 0:20:46To give you an example, in his house,
0:20:46 > 0:20:51he was so obsessed with not wasting water, and in those days,
0:20:51 > 0:20:52they had no showers, they used to have baths,
0:20:52 > 0:20:55and he had three daughters so there were five of them in the house.
0:20:55 > 0:20:57All this hot water was just being wasted.
0:20:57 > 0:21:01He couldn't bear this, so what he invented was a channel system
0:21:01 > 0:21:04where the waste water from the bath went into his greenhouse,
0:21:04 > 0:21:06provided a heat exchanger in the greenhouse,
0:21:06 > 0:21:09and it enabled him to grow nectarines in Sussex.
0:21:09 > 0:21:10MARK CHUCKLES
0:21:10 > 0:21:12That's so brilliant.
0:21:12 > 0:21:15Harry could see that the key to improving the performance
0:21:15 > 0:21:19of diesel engines lay in the way they burned their fuel.
0:21:19 > 0:21:23Because diesel is a heavier oil than petrol, it is less volatile
0:21:23 > 0:21:26and harder to make burn.
0:21:26 > 0:21:29The key was, how can I burn this fuel efficiently?
0:21:29 > 0:21:30Mix up the air and the fuel?
0:21:30 > 0:21:34Diesel, it's not volatile and you've got to try and sheer the fuel,
0:21:34 > 0:21:37break it down into tiny, tiny droplets.
0:21:37 > 0:21:41Harry's solution was the Comet - a pre-chamber that the fuel
0:21:41 > 0:21:45entered before hitting the combustion chamber.
0:21:45 > 0:21:49This ingenious component helped mix the air and the fuel
0:21:49 > 0:21:52so that the combustion was improved.
0:21:52 > 0:21:55Unique slow-motion footage shot in the 1970s
0:21:55 > 0:22:02shows the incredible swirling of fuel and air created by the Comet chamber.
0:22:02 > 0:22:05The imaging is utterly beautiful, isn't it?
0:22:06 > 0:22:12On the left is the Comet pre-chamber, on the right, the combustion chamber.
0:22:12 > 0:22:15So now here's the pre-chamber, the swirling pre-chamber for the Comet.
0:22:15 > 0:22:19The fuel's injected, it burns, straight out of the throat
0:22:19 > 0:22:22and forms two contra-rotating vortices...
0:22:22 > 0:22:24- Oh, OK.- ..to complete combustion.
0:22:24 > 0:22:28Having a Comet chamber is what allows, essentially,
0:22:28 > 0:22:31the perfect burn and the perfect burn gives you the most power.
0:22:31 > 0:22:35And that, in terms of its application in road-going vehicles
0:22:35 > 0:22:37particularly, that would have been utterly critical.
0:22:37 > 0:22:39That's right.
0:22:39 > 0:22:40It's mesmerising.
0:22:44 > 0:22:49The Comet pre-chamber was patented in 1931.
0:22:49 > 0:22:55Its unprecedented power was showcased in 1933 when Britain's George Eyston
0:22:55 > 0:23:00broke the world diesel land speed record in a Comet-powered car.
0:23:00 > 0:23:03- VINTAGE RECORDING:- Today, I have driven it on Brooklands track
0:23:03 > 0:23:07and it has achieved a speed of over 106mph.
0:23:07 > 0:23:12Incidentally, the fuel oil engine is the most economical one to run.
0:23:12 > 0:23:15The fuel consumption is so low that on my record run
0:23:15 > 0:23:18today at Brooklands, it only cost me thruppence.
0:23:18 > 0:23:21The Ricardo Comet's first customer was AEC,
0:23:21 > 0:23:25the company that built London's buses.
0:23:25 > 0:23:26It was a staggering success.
0:23:26 > 0:23:29The London General Omnibus Company were overwhelmed with
0:23:29 > 0:23:31the smoothness of the engines
0:23:31 > 0:23:33and they were, above all, very clean,
0:23:33 > 0:23:36they were smoke-free, it was a revelation for the time.
0:23:36 > 0:23:38And, of course, extremely economical, it was saving them a lot
0:23:38 > 0:23:42of money in terms of running costs, that was the drive for doing it.
0:23:42 > 0:23:44Within a few decades,
0:23:44 > 0:23:48London's entire bus fleet had converted to diesel engines.
0:23:48 > 0:23:52Because of the success of the London bus application, everybody wanted
0:23:52 > 0:23:57to license these engines and they ended up in many different vehicles.
0:23:57 > 0:24:00As the '30s rolled on, taxi, bus, coach
0:24:00 > 0:24:03and road haulage operators across Britain
0:24:03 > 0:24:08and the world were converting their fleets to diesel engines.
0:24:09 > 0:24:13Almost all of these were powered by Ricardo Comet pre-chambers
0:24:13 > 0:24:15or others like it.
0:24:17 > 0:24:22The only failure for Harry Ricardo's Comet was the car I'm driving -
0:24:22 > 0:24:25the Citroen Rosalie.
0:24:25 > 0:24:28So why didn't it take off in the passenger car, then?
0:24:28 > 0:24:31Petrol engines are more refined, they're smoother.
0:24:31 > 0:24:34Diesel had a bit of a reputation for being a bit rough in taxis,
0:24:34 > 0:24:36it hadn't been properly refined, there wasn't the need.
0:24:36 > 0:24:40Even though the lighter, more powerful petrol engine
0:24:40 > 0:24:44still dominated the car market in the 1930s,
0:24:44 > 0:24:48thanks to the Comet, diesel's takeover of the roads had begun.
0:24:48 > 0:24:53The Comet chamber is a true piece of British engineering genius.
0:24:53 > 0:24:54It put Britain at the forefront
0:24:54 > 0:24:58of high-speed diesel road vehicle engineering.
0:24:58 > 0:25:00Today, driving along the road,
0:25:00 > 0:25:04pretty much every vehicle you see bigger than a family car
0:25:04 > 0:25:10is powered by a diesel engine and it all started right here.
0:25:14 > 0:25:20By the end of the 1930s, Europe had returned to war once again.
0:25:20 > 0:25:24In Germany, Rudolf Diesel became a propaganda hero
0:25:24 > 0:25:30when the Nazi film ministry produced a biopic in 1942.
0:25:31 > 0:25:36The film spotlighted his engine's contribution to the Nazi war effort,
0:25:36 > 0:25:40something I suspect would have mortified Rudolf.
0:25:40 > 0:25:45Tellingly, the film doesn't deal with the subject of Diesel's death
0:25:45 > 0:25:48but a key montage did hint at the next stage
0:25:48 > 0:25:51in the story of his engine.
0:25:51 > 0:25:55Among the submarines and trucks were these - tractors.
0:25:58 > 0:26:02The war would leave most of Europe facing food shortages
0:26:02 > 0:26:05and in the '50s, Britain began a programme
0:26:05 > 0:26:08to increase its self-sufficiency in food production.
0:26:10 > 0:26:15It's places like this vintage vehicles rally in Cheshire where you
0:26:15 > 0:26:20can trace the role the diesel engine would play in what was to come.
0:26:20 > 0:26:24Mechanisation of British farming had started before the war with
0:26:24 > 0:26:26steam engines like these.
0:26:26 > 0:26:29I'll tell you what, they are beautiful, aren't they?
0:26:29 > 0:26:31Utterly magnificent machines.
0:26:31 > 0:26:33I mean, they're kind of like a crossover between the days
0:26:33 > 0:26:36of the working horse with all the regalia they wore
0:26:36 > 0:26:38and it was about showmanship.
0:26:38 > 0:26:40They are works of art.
0:26:40 > 0:26:42But in terms of practicality...
0:26:43 > 0:26:46It's just never going to work, steam, is it?
0:26:46 > 0:26:51Steam tractors were still in use on British farms in the 1950s.
0:26:51 > 0:26:55One man who can attest to that is lifetime farmer Dick Walker.
0:26:57 > 0:27:00- Dick, how old are you? - 84.- Are you really?- Yeah.
0:27:00 > 0:27:02You don't look a day over...57.
0:27:02 > 0:27:06- I was driving a steam engine when I was 15 years old.- Really?- Yeah.
0:27:06 > 0:27:10- A big one?- A big one. Full-size steam engine.
0:27:10 > 0:27:14It must be so much work getting a steam engine going...
0:27:14 > 0:27:16Oh, you had to be there an hour before you were
0:27:16 > 0:27:20ready in the morning to light the fire and get steam up.
0:27:20 > 0:27:22And then keeping it going all day long?
0:27:22 > 0:27:26Keep stoking it up about every half hour all day
0:27:26 > 0:27:31and filling it with water, hosepipe and coal all day long.
0:27:31 > 0:27:35Britain's self-sufficiency plan meant upgrading the country's agriculture
0:27:35 > 0:27:38with modern farm machinery.
0:27:38 > 0:27:41Initially, this was done with petrol-powered tractors
0:27:41 > 0:27:44like these, the famous Little Grey Fergie.
0:27:46 > 0:27:50But in 1953, the UK's first mass-produced diesel-powered
0:27:50 > 0:27:55tractor arrived - the Fordson Diesel Major.
0:27:55 > 0:27:58And this would change everything.
0:27:58 > 0:28:03Farmers are notorious for being quite conservative when it comes to
0:28:03 > 0:28:07decision-making but it was these tractors, Fordson Majors, the classic
0:28:07 > 0:28:12blue and orange, that convinced farmers that diesel was the future.
0:28:12 > 0:28:16'Dick was one of the farmers who soon traded his petrol machine
0:28:16 > 0:28:19'for a Fordson diesel.'
0:28:19 > 0:28:22So, you've had a love affair with these your whole life, really?
0:28:22 > 0:28:26I've got 17 at home, tractors, all vintage.
0:28:26 > 0:28:29Here, just down the road, I only live two mile away.
0:28:29 > 0:28:32I started collecting them 40 years ago.
0:28:33 > 0:28:37The attraction of diesel tractors over petrol began with
0:28:37 > 0:28:42their efficiency and lower running costs, but it didn't end there.
0:28:42 > 0:28:45Petrol engines weren't ideal for outdoor conditions.
0:28:45 > 0:28:50In cold weather, they had to use both petrol and paraffin fuel to operate.
0:28:50 > 0:28:54And the petrol engine's spark plugs could malfunction
0:28:54 > 0:28:56in the damp and rain.
0:28:56 > 0:29:00Were farmers difficult to convince that actually diesel was the future?
0:29:00 > 0:29:03Well, the diesel was a lot easier cos there was no petrol,
0:29:03 > 0:29:08starting on petrol and getting it warm and turning it on paraffin
0:29:08 > 0:29:12and once you started it on diesel, you could go all day, like.
0:29:12 > 0:29:14And cheaper to run.
0:29:14 > 0:29:17Just get it on, press the starter and go.
0:29:17 > 0:29:21But the diesel engine had another attribute that made it better suited
0:29:21 > 0:29:25to the rigours of agriculture than the petrol engine.
0:29:25 > 0:29:30And I'm in a good place to demonstrate what this was.
0:29:30 > 0:29:35Welcome to the brilliantly bonkers world of competitive tractor pulling.
0:29:35 > 0:29:39So, the big question in the '50s was diesel versus petrol,
0:29:39 > 0:29:41so we're going to put it to the test.
0:29:41 > 0:29:45We have a 1950s diesel here, we have a 1950s petrol over here.
0:29:45 > 0:29:50They are both going to compete on the pull. We have a crowd.
0:29:50 > 0:29:52What we need is a driver.
0:29:55 > 0:29:56If you've never seen tractor pulling,
0:29:56 > 0:29:58let me give you a sense of what it is.
0:29:58 > 0:30:01This is just like an Arctic Truck trailer
0:30:01 > 0:30:04which has got a great big weight on the back of it here.
0:30:04 > 0:30:08The weight at the back of the trailer moves towards the front
0:30:08 > 0:30:11the further the tractor pulls.
0:30:11 > 0:30:15The trailer has a sled at the front that digs into the ground.
0:30:15 > 0:30:17This basically means the longer you pull,
0:30:17 > 0:30:22the more load is put on your engine and, eventually, the tractor stalls.
0:30:22 > 0:30:24I've never done this before, I have to say.
0:30:24 > 0:30:27I've driven a lot of tractors, but I've never done a tractor pull.
0:30:27 > 0:30:31Our demonstration will start with this intimidating beast -
0:30:31 > 0:30:35a 1950s petrol-powered tractor.
0:30:35 > 0:30:37Let's see how far this one gets.
0:30:39 > 0:30:44Just like tractors working the field, in a pull, you have to keep
0:30:44 > 0:30:50your engine in low gear until, as the load increases, the engine stalls.
0:30:50 > 0:30:54So that is how far the petrol managed to pull the sled, so we're taking it
0:30:54 > 0:30:57all the way back to the start and now we'll hook up the diesel.
0:30:59 > 0:31:04Dick's kindly lending me his very own 1950s diesel-powered Fordson.
0:31:06 > 0:31:07Now, this isn't exactly science,
0:31:07 > 0:31:11but let's put diesel's pulling power to the test.
0:31:12 > 0:31:14It's a while since I drove a tractor.
0:31:18 > 0:31:19Hey!
0:31:19 > 0:31:22But by some minor miracle...
0:31:25 > 0:31:29..I get further than the petrol tractor did.
0:31:29 > 0:31:34- Did I beat it?- Yeah.- Yes! By about ten feet, that's good enough!
0:31:34 > 0:31:37Bring on the diesels!
0:31:37 > 0:31:42What we've just seen in action is another of the diesel engine's USPs -
0:31:42 > 0:31:45the fact that in low gears and with heavy loads,
0:31:45 > 0:31:49the diesel engine is less prone to stalling than a petrol engine.
0:31:49 > 0:31:54This made the diesel perfect for agricultural work.
0:31:54 > 0:31:56Well, there you go, there wasn't a lot in it,
0:31:56 > 0:31:59but these were the very early diesel engines.
0:31:59 > 0:32:02It just got better and better from here on in.
0:32:02 > 0:32:05With lower revving, torque-ier engines
0:32:05 > 0:32:08that could just haul and work all day long,
0:32:08 > 0:32:12the diesel engine had become the farmers' friend.
0:32:12 > 0:32:16'The Fordson Diesel Major led a breakthrough for the diesel
0:32:16 > 0:32:19'engine in British agriculture.
0:32:19 > 0:32:20'By the end of the '50s,
0:32:20 > 0:32:25'the market for petrol tractors in the UK had all but disappeared.
0:32:25 > 0:32:29'Today, you'd be lucky to find any agricultural machinery in this
0:32:29 > 0:32:32'country that's not diesel.
0:32:32 > 0:32:35'Across the world, the picture has been the same.
0:32:35 > 0:32:40'Between the '50s and the '80s, the world's population almost doubled.
0:32:41 > 0:32:46'Diesel engine helped feed these new mouths.
0:32:46 > 0:32:50'From tractors to harvesters, forklifts to forestry machines,
0:32:50 > 0:32:54'global agriculture is now almost completely
0:32:54 > 0:32:56'reliant on the diesel engine.
0:32:59 > 0:33:03'But while the diesel was feeding an increasingly populous world,
0:33:03 > 0:33:06'there was still the matter of how that population got around.
0:33:08 > 0:33:09'For the best part of 150 years,
0:33:09 > 0:33:13'the most efficient way of doing that had been rail transport.
0:33:15 > 0:33:19'Rudolf Diesel himself had overseen early trials of diesel powered
0:33:19 > 0:33:21'locomotives in Germany.
0:33:23 > 0:33:24'And by the 1950s,
0:33:24 > 0:33:28'diesel trains were well established in countries like the US.
0:33:32 > 0:33:34'Here, however, things took longer'
0:33:34 > 0:33:37because countries like Britain that had vast reserves of coal
0:33:37 > 0:33:40found it much harder to wean themselves off steam power.
0:33:40 > 0:33:42As far as rail was concerned,
0:33:42 > 0:33:47Britain remained hooked on steam far longer than it should have.
0:33:47 > 0:33:51'In 1955, for the first time ever,
0:33:51 > 0:33:56'the largely steam driven British rail network was running at a loss.
0:33:56 > 0:33:59'Increased competition from road transport,
0:33:59 > 0:34:04'much of it now running on diesel, was eating away at rail profits.
0:34:05 > 0:34:11'And when British Railways published its 1955 modernisation plan,
0:34:11 > 0:34:15'it recommended that much of the network convert to diesel power.
0:34:17 > 0:34:21'To understand why, I'm at Britain's last remaining working railway
0:34:21 > 0:34:24'roundhouse in Derbyshire.
0:34:24 > 0:34:27'Its manager is Mervyn Allcock.'
0:34:27 > 0:34:29Mervyn.
0:34:29 > 0:34:30- Hello.- Hello.
0:34:30 > 0:34:33- Mark.- Good to meet you, Mark. - Nice to see you.
0:34:33 > 0:34:37'It was in these roundhouses that the earliest British experiments
0:34:37 > 0:34:40'with diesel engines in trains were made.
0:34:40 > 0:34:42'And these were the subjects.
0:34:42 > 0:34:46'The humble shunters, the workhorses of the rail yards.'
0:34:46 > 0:34:48- So that's this kind of locomotive? - Yes.
0:34:48 > 0:34:51It's the first train you always had on your kid's train set, isn't it?
0:34:51 > 0:34:54- It is, yes.- When you couldn't afford the really, really expensive,
0:34:54 > 0:34:57- like the Flying Scotsman.- That's right, you bought a little shunter.
0:34:57 > 0:35:02- You bought a little shunter, didn't you?- Yeah.- What a treat!
0:35:02 > 0:35:05- This is my kind of cockpit, Merv! - It's fabulous.
0:35:05 > 0:35:08It's fabulous, isn't it? It's basic engineering, but fabulous.
0:35:08 > 0:35:13- Proper dials, big levers. What's not to love about that?- Yeah! Indeed.
0:35:13 > 0:35:15- So, can we fire this one up? - We can, yes.
0:35:15 > 0:35:19'It didn't take long for the diesel engine to win over those who
0:35:19 > 0:35:22- 'had to work with it.' - Push the master switch on.- OK.
0:35:22 > 0:35:25- And then, if you want to press the starter button.- Here we go.
0:35:25 > 0:35:26There you go.
0:35:26 > 0:35:30ENGINE STARTS
0:35:30 > 0:35:32There it goes, that's it.
0:35:32 > 0:35:34My God! What a difference...
0:35:34 > 0:35:37Instantly, what a difference to if you were running a steam engine.
0:35:37 > 0:35:40Oh, quite. You would have to get up many hours earlier,
0:35:40 > 0:35:41starting the fire,
0:35:41 > 0:35:44waiting for the steam pressure to build up.
0:35:44 > 0:35:46So, you'd have a team of blokes who would have to get up
0:35:46 > 0:35:49at like four o'clock or something to get the whole thing going...
0:35:49 > 0:35:50That's exactly it.
0:35:50 > 0:35:55'And now comes the realisation of a childhood dream, to drive a train.'
0:35:55 > 0:35:57- Your hand on the brake.- Yeah.
0:35:57 > 0:36:00And if you just toot the horn, to say we're moving.
0:36:00 > 0:36:02- Press it downwards. - HORN TOOTS
0:36:02 > 0:36:06- Ha-ha!- And then take the brake off. - OK, yeah.
0:36:06 > 0:36:08Right.
0:36:08 > 0:36:11- Give it a little bit of throttle. - So, a little bit of throttle there.
0:36:11 > 0:36:14- Yeah.- Oh, my God! I'm driving a train.
0:36:14 > 0:36:16I'm actually driving a train.
0:36:16 > 0:36:18TOOTS HORN
0:36:18 > 0:36:22- Get into second?- Yeah. Drop the throttle off, change to second.
0:36:22 > 0:36:25And again. That's it.
0:36:25 > 0:36:28Ho-ho! Gear change! In a train!
0:36:28 > 0:36:30'The stock in trade of the shunter
0:36:30 > 0:36:33'was moving other trains about the yard.'
0:36:33 > 0:36:36So we're going to hook up to the yellow one on the right, are we?
0:36:36 > 0:36:37Yeah.
0:36:37 > 0:36:40A little bit of brake.
0:36:40 > 0:36:42Slowing us down.
0:36:43 > 0:36:46And...that's it, we're on.
0:36:46 > 0:36:50That close manoeuvring there, it's very subtle for a big, heavy thing.
0:36:50 > 0:36:53- Absolutely, yeah. - In a steam, what would you have to
0:36:53 > 0:36:55do to be able to do this kind of close manoeuvring?
0:36:55 > 0:37:00- You'd have to be very skilled.- How heavy is what we're going to pull?
0:37:00 > 0:37:02It's over 100 tonnes.
0:37:02 > 0:37:06- You can really feel it there.- You feel you've got it now, don't you?
0:37:06 > 0:37:07Oh, my God!
0:37:07 > 0:37:12'This is one of the most easy to use vehicles I've ever driven.'
0:37:12 > 0:37:16That is actually so easy. Even an idiot can do it.
0:37:17 > 0:37:23Honestly. I mean, having never driven a train, I've just shunted 12 tonnes.
0:37:23 > 0:37:27And I tell you what really gets you is the subtlety of that.
0:37:27 > 0:37:32- For something so heavy, you can... The fine...- The control is there.
0:37:32 > 0:37:34The control is incredible.
0:37:34 > 0:37:36- Yeah.- Absolutely incredible.- It is.
0:37:36 > 0:37:40Just ten minutes in here and you can see why the diesel shunter
0:37:40 > 0:37:43completely revolutionised this kind of work.
0:37:45 > 0:37:48'In the years following British Railways' modernisation plan,
0:37:48 > 0:37:52'it wasn't just the network shunters that got diesel engines,
0:37:52 > 0:37:55'but locomotives of all kinds.
0:37:57 > 0:38:01'By the early 1960s, most of the fleet had been converted to diesel.
0:38:02 > 0:38:06'But among the lines that hadn't was the East Coast Mainline.'
0:38:08 > 0:38:12This was the prestigious line between London and Edinburgh,
0:38:12 > 0:38:14the domain of the Flying Scotsman.
0:38:14 > 0:38:18It was, if you like, the racetrack of the rail network.
0:38:18 > 0:38:24Long, straight and flat, it cried out for a racehorse of an engine.
0:38:24 > 0:38:30Something that would put Britain at the forefront of diesel train power.
0:38:30 > 0:38:32The Deltic.
0:38:32 > 0:38:35'The Deltic is one of the most incredible
0:38:35 > 0:38:38'stories in the history of British Rail.
0:38:38 > 0:38:41'This is the home of the Deltic Preservation Society,
0:38:41 > 0:38:46'which has been safeguarding these locomotives for nearly 40 years.
0:38:46 > 0:38:51'What makes these trains so special are their diesel engines,
0:38:51 > 0:38:55'which is where I can find technician Alex Williams at work.'
0:38:55 > 0:38:59- Alex.- Hello, Mark.- They don't leave much space for humans!
0:38:59 > 0:39:01Mind your head as you're coming down.
0:39:01 > 0:39:05- This is such a beast. It's huge. - Welcome to the heart of the machine.
0:39:05 > 0:39:08So, you're already into a job then here. What's going on?
0:39:08 > 0:39:10We're pressure testing this unit
0:39:10 > 0:39:12because it's had some coolant issues.
0:39:12 > 0:39:16'The Deltic engine is a diesel like no other.'
0:39:16 > 0:39:18This all looks a bit odd to me,
0:39:18 > 0:39:21a bit upside down, cos I'm looking down into the underside
0:39:21 > 0:39:24of a piston here, but I'm also looking at a piston here.
0:39:24 > 0:39:28And it's just the same underneath and on the other side.
0:39:28 > 0:39:32'What I can't see in this engine compartment is that the Deltic
0:39:32 > 0:39:35'engine takes its name from its triangular shape,
0:39:35 > 0:39:38'derived from the Greek letter Delta.'
0:39:38 > 0:39:39Is that unique?
0:39:39 > 0:39:42The idea of having them in a triangle is very much unique.
0:39:42 > 0:39:45It's kind of like the Formula 1 engine of diesel trains.
0:39:45 > 0:39:47Very much so.
0:39:47 > 0:39:52'This very special engine has a story with a very unlikely beginning.
0:39:54 > 0:39:57'In the mid 1930s, the German Luftwaffe was experimenting
0:39:57 > 0:40:02'with a diesel engine powerful enough to use in its JU86 Bomber aircraft.
0:40:04 > 0:40:09'The design was acquired by the British engineering company Napier
0:40:09 > 0:40:11'in 1939. And after the war,
0:40:11 > 0:40:16'the Royal Navy installed these diesels in motor torpedo boats.
0:40:16 > 0:40:20'Alan Vessey was an engineer who worked for the Navy
0:40:20 > 0:40:21'on the Deltic project.'
0:40:21 > 0:40:26- So you know them inside out.- Well, yes. I hope I know more than most.
0:40:26 > 0:40:30So, what did it feel like to be part of a team,
0:40:30 > 0:40:33working on something that was so state of the art?
0:40:33 > 0:40:37It was remarkably complex at first.
0:40:37 > 0:40:42And it was also top secret for the Admiralty.
0:40:42 > 0:40:47Therefore, you couldn't openly discuss it in the engineering
0:40:47 > 0:40:52world until the first engines had been successful in the first ships.
0:40:52 > 0:40:55So you couldn't go down the pub and start bragging with your mates...
0:40:55 > 0:40:57Not really, no.
0:40:57 > 0:40:59'What made the original Luftwaffe engine
0:40:59 > 0:41:04'so unique was something called opposing pistons.
0:41:04 > 0:41:08'In any normal diesel engine, a single piston ignites
0:41:08 > 0:41:12'fuel by compressing air against the top of the cylinder.
0:41:12 > 0:41:16'With opposing pistons, there are two pistons in each cylinder
0:41:16 > 0:41:21'and they ignite the fuel by compressing air against one another.'
0:41:21 > 0:41:24So you're getting double the bang for your buck, if you like.
0:41:24 > 0:41:28- You're getting twice the amount of power out of this thing?- Yes.
0:41:28 > 0:41:32'But Napier took the opposing pistons concept to another level
0:41:32 > 0:41:35'when it created the Deltic engine.
0:41:35 > 0:41:38'They put three sets of opposing pistons
0:41:38 > 0:41:42'together in the inverted triangle shape.
0:41:42 > 0:41:45'Each Deltic engine comprised six of these triangular
0:41:45 > 0:41:52'arrays for a total of 36 pistons in a remarkably small space.'
0:41:52 > 0:41:58So at 1,500 revs, with six banks operating,
0:41:58 > 0:42:04you get 25 combustions in these cylinders per second.
0:42:04 > 0:42:05That is the lower speed.
0:42:07 > 0:42:10'So, when it came to choosing an engine to replace
0:42:10 > 0:42:14'the Flying Scotsman, there was only one contender.
0:42:15 > 0:42:19'When the first Deltic took to the tracks in 1961,
0:42:19 > 0:42:22'it was the most powerful train in the world.
0:42:24 > 0:42:28'It shaved an hour off the time from London to Edinburgh.
0:42:30 > 0:42:35'The Deltic was to rail transport what Concorde was to aviation -
0:42:35 > 0:42:39'the most advanced, most powerful technology of its kind.'
0:42:39 > 0:42:44In its day, it was the world's fastest locomotive.
0:42:44 > 0:42:48You might say the Luftwaffe had a hand in the greatest
0:42:48 > 0:42:50story in British Rail's history.
0:42:50 > 0:42:57In 1960, British Railways built its last steam locomotive,
0:42:57 > 0:43:01but it wasn't just the age of steam trains that was ending.
0:43:01 > 0:43:03On the global scale,
0:43:03 > 0:43:08it was the great era of steam itself that was finally closing.
0:43:09 > 0:43:15In 1964, the share of the world's power generated from coal
0:43:15 > 0:43:18fell below 50% for the first time.
0:43:19 > 0:43:23We had entered a new epoch of energy production,
0:43:23 > 0:43:26an age increasingly powered by the diesel engine.
0:43:30 > 0:43:32By the early 1970s,
0:43:32 > 0:43:35the diesel engine was winning the race against the petrol engine in
0:43:35 > 0:43:40almost all modes of land transport, with one notable exception - cars.
0:43:43 > 0:43:45But that was about to change.
0:43:45 > 0:43:50In 1973, the Arab nations announced an oil embargo,
0:43:50 > 0:43:53following war with Israel.
0:43:53 > 0:43:55The price of petrol skyrocketed.
0:43:55 > 0:43:59With the spotlight on fuel efficiency, the quest was on to
0:43:59 > 0:44:03design diesel engines that could replace their more inefficient
0:44:03 > 0:44:06petrol cousins.
0:44:06 > 0:44:10And the story of how this happened can be best told from a company
0:44:10 > 0:44:12that was at its heart.
0:44:12 > 0:44:17When we want a new diesel, we go to a car dealership, but when a car
0:44:17 > 0:44:20manufacturer wants a new diesel engine,
0:44:20 > 0:44:25they come to places like this - Delphi, one of the world's most
0:44:25 > 0:44:27advanced diesel engine fuel
0:44:27 > 0:44:31injection research and development centres.
0:44:31 > 0:44:35'Ken Smith is a senior engineer at Delphi, who can help me
0:44:35 > 0:44:40'understand how the diesel engine hijacked the car market.'
0:44:40 > 0:44:43Until the oil crisis,
0:44:43 > 0:44:48diesels had been more or less sidelined as work vehicles only.
0:44:48 > 0:44:52And then in the '70s, the oil crisis comes along, everyone realises
0:44:52 > 0:44:56we've really got to worry about the fuel economy of these things.
0:44:56 > 0:45:00'The problem facing diesel engine designers was how to compete
0:45:00 > 0:45:04'with petrol's power and performance.
0:45:04 > 0:45:07'Initially, the answer appeared to be the Comet swirl chamber
0:45:07 > 0:45:12'technology Harry Ricardo had trailblazed back in the '30s.'
0:45:12 > 0:45:16Companies like Volkswagen, Peugeot, Citroen,
0:45:16 > 0:45:20they started to develop very efficient engines...
0:45:20 > 0:45:23The same system that Harry Ricardo came up with that
0:45:23 > 0:45:27- went into the early diesel mass produced cars.- Yes.
0:45:27 > 0:45:32'But the Comet pre-chamber had its limitations and 1970s diesels
0:45:32 > 0:45:36'were still underpowered, compared to their petrol counterparts.
0:45:37 > 0:45:41'The answer was to do away with the pre-chamber and instead,
0:45:41 > 0:45:45'inject the fuel directly into the combustion chamber.
0:45:45 > 0:45:50'This had previously been impossible to perfect in small engines,
0:45:50 > 0:45:57'until Delphi put a direct injection fuel pump into a 1984 Ford Transit.'
0:45:57 > 0:46:01So the Transit, one of the most iconic vehicles of all time,
0:46:01 > 0:46:04was that a pivotal moment, in terms of the development
0:46:04 > 0:46:07- of the diesel engine that ultimately would come into cars?- Yes.
0:46:07 > 0:46:10That was a very efficient small commercial vehicle
0:46:10 > 0:46:15and it was the first one that introduced a 4,000 RPM diesel
0:46:15 > 0:46:17engine with direct injection systems,
0:46:17 > 0:46:22the same concept that is now applied across everything today.
0:46:22 > 0:46:25'Powered by direct injection technology,
0:46:25 > 0:46:30'sales of diesels soared in Europe in the '80s and '90s.
0:46:30 > 0:46:33'Environmental concerns helped fuel this demand,
0:46:33 > 0:46:39'as diesel engines emitted much less carbon dioxide than petrol.
0:46:39 > 0:46:40'By the end of the '90s,
0:46:40 > 0:46:44'the diesel engine's assault on Europe's car market
0:46:44 > 0:46:49'was in full swing, something that would have delighted Rudolf Diesel.
0:46:49 > 0:46:52'He had written that his life's work would be complete
0:46:52 > 0:46:56'when his engine was powering motor cars.
0:46:56 > 0:46:59'It may be a little behind schedule, but today,
0:46:59 > 0:47:02'half the new cars in Europe are diesel.
0:47:05 > 0:47:09'But perhaps Rudolf wasn't setting his sights high enough
0:47:09 > 0:47:13'when it came to what his engine might eventually achieve
0:47:13 > 0:47:17'because the diesel engine's biggest contribution to the modern world
0:47:17 > 0:47:21'hasn't been on the roads, but out at sea,
0:47:21 > 0:47:25'something I've come to Felixstowe, Britain's busiest port, to witness.'
0:47:25 > 0:47:31It's when you visit a container ship port like this that the extent of the
0:47:31 > 0:47:37diesel engine's role in the modern global economy becomes very apparent.
0:47:39 > 0:47:44'Today's world of intercontinental global trade depends on ocean
0:47:44 > 0:47:49'transport to move billions of tonnes of resources and goods each year.
0:47:49 > 0:47:54'The engine that has made this feasible is the ultra large
0:47:54 > 0:47:56'Marine Diesel Engine.'
0:47:56 > 0:48:00And I'm about to see one of the most modern examples.
0:48:00 > 0:48:03It powers this hulking great container ship.
0:48:03 > 0:48:10'In 1982, the first giant marine engines with over 50% efficiency
0:48:10 > 0:48:14'were introduced to power container ships like these.'
0:48:14 > 0:48:17The scale of this thing is absolutely mind-blowing.
0:48:17 > 0:48:20'This is the Ever Lunar,
0:48:20 > 0:48:25'the newest vessel in Taiwanese shipping company, Evergreen's fleet.
0:48:25 > 0:48:29'It's a dedicated container ship carrying thousands
0:48:29 > 0:48:32'of the now-standardised 20-foot containers.
0:48:32 > 0:48:35'Melvin Lin is the company's chief captain
0:48:35 > 0:48:39'and has served over 30 years at sea.'
0:48:39 > 0:48:41- Captain Melvin?- Glad to meet you.
0:48:41 > 0:48:43Hello. Mark. Nice to see you.
0:48:43 > 0:48:48- This is an amazing ship.- Thank you. - So, how big is it?
0:48:48 > 0:48:53We can carry about 8,500 20-foot containers.
0:48:53 > 0:48:56- So, these kind of containers that we're looking at now?- Yes.
0:48:56 > 0:48:57That's a lot of containers.
0:48:57 > 0:49:01'The efficiency of the diesel engine on this ship
0:49:01 > 0:49:03'gives it astonishing range.'
0:49:03 > 0:49:05The vessel's maximum range will be
0:49:05 > 0:49:08around 55,000 nautical miles,
0:49:08 > 0:49:13which is more than 100,000 kilometres.
0:49:13 > 0:49:17- That's twice the way around the Earth.- That's right.
0:49:17 > 0:49:20- Before we can refuel it. - That's extraordinary.
0:49:20 > 0:49:25And how many crew are needed to manage the ship?
0:49:25 > 0:49:28Around 14 to 16, it depends.
0:49:28 > 0:49:31- 14 to 16?- It's fully computerised.
0:49:31 > 0:49:34'These controls hook up to an engine
0:49:34 > 0:49:38'on a scale I've never before witnessed.
0:49:38 > 0:49:41'Even getting to the engine room can induce vertigo.'
0:49:41 > 0:49:45So, from the bridge, how many floors down to the engine room?
0:49:45 > 0:49:49From the top to the bottom, there's one, two, three, four, five,
0:49:49 > 0:49:51six, seven, eight, nine, ten.
0:49:51 > 0:49:54- Ten.- That's to the bottom. But now, we're only here.- OK.
0:49:54 > 0:49:58- So nine floors we've got to go down in the lift?- That's right.
0:50:00 > 0:50:04OK. So this is the control room?
0:50:04 > 0:50:05Main engine control room.
0:50:07 > 0:50:12'The engine room itself is like a cathedral of power.'
0:50:12 > 0:50:15So this is the top, how far does it go down?
0:50:15 > 0:50:19- We have to go down four floors. - Four floors?
0:50:19 > 0:50:23An engine that's four floors. For this, five floors.
0:50:23 > 0:50:26That's bigger than my house.
0:50:26 > 0:50:28'It's the size of these nine cylinders
0:50:28 > 0:50:32'that gives the engine its huge power.
0:50:32 > 0:50:37'The space inside the cylinders, the displacement, is measured in litres.
0:50:37 > 0:50:43'And together, these nine cylinders displace 18,500 litres.
0:50:43 > 0:50:46'Your car at home probably has two litres.'
0:50:48 > 0:50:50So, how many horsepower? What's the power of this?
0:50:50 > 0:50:5475,190 horsepower.
0:50:54 > 0:50:55OK. Hang on a minute, then. 70...
0:50:55 > 0:50:58Hold on, I'm going to do some maths now.
0:50:58 > 0:51:0275,190. Right, I'm going to divide that by...
0:51:02 > 0:51:06- Say 150 horsepower is a reasonably-powerful car?- Yeah.
0:51:06 > 0:51:09That's, like, 501 cars.
0:51:09 > 0:51:14500 BMW 250 injection.
0:51:14 > 0:51:15That's a lot of power.
0:51:15 > 0:51:17It's a big, big ship.
0:51:17 > 0:51:22All large commercial ships use diesel engines like these.
0:51:22 > 0:51:24Not just all the container ships,
0:51:24 > 0:51:27but the tankers and bulk carriers, too.
0:51:28 > 0:51:31It's incredibly hard to give you a sense
0:51:31 > 0:51:34of just how massive this diesel engine is.
0:51:34 > 0:51:37But if you think behind the end wall there
0:51:37 > 0:51:39is the propeller for this ship,
0:51:39 > 0:51:41that if it was in this engine room,
0:51:41 > 0:51:44it would fill it from a width point of view and more.
0:51:44 > 0:51:46But it's driven by a prop shaft
0:51:46 > 0:51:51that runs through these bearings all the way to the engine.
0:51:51 > 0:51:54So the engine is the big green thing here you can see.
0:51:54 > 0:51:56The flywheel is behind this arch.
0:51:56 > 0:52:00But there are nine cylinders down here.
0:52:00 > 0:52:03One, two, three, four, five, six,
0:52:03 > 0:52:06seven, eight, nine cylinders.
0:52:06 > 0:52:11Now we're going up. On this level, we have
0:52:11 > 0:52:13turbo one...
0:52:16 > 0:52:18..turbo two...
0:52:20 > 0:52:22..and turbo three.
0:52:24 > 0:52:27And the top floor of the engine, here you go.
0:52:27 > 0:52:29This is the top of the cylinders.
0:52:29 > 0:52:32It's a colossally huge engine, this.
0:52:32 > 0:52:34I mean, it's just massive!
0:52:34 > 0:52:37The numbers themselves just speak volumes.
0:52:37 > 0:52:41It weighs 1,800 tonnes.
0:52:41 > 0:52:45It's 75,000 horsepower.
0:52:45 > 0:52:48It's 18,000 litres.
0:52:48 > 0:52:53But what's perhaps most extraordinary is that in essence,
0:52:53 > 0:52:58this is the same machine as Rudolf Diesel's original design.
0:52:58 > 0:53:01100 years on, one man's invention
0:53:01 > 0:53:05is powering the biggest ships in the world.
0:53:07 > 0:53:12'I've only got a few minutes left before the Ever Lunar leaves port.
0:53:12 > 0:53:15'So just time enough to see something very special.'
0:53:15 > 0:53:20We're about to fire up one of the biggest engines in the world.
0:53:20 > 0:53:23It starts with compressed air,
0:53:23 > 0:53:26so some engines behind you will kick in first.
0:53:30 > 0:53:32Really tense, this.
0:53:40 > 0:53:43Here it goes. Here it goes now!
0:53:43 > 0:53:4718,000 litres is now alive!
0:53:47 > 0:53:50Look at that! Incredible!
0:53:50 > 0:53:55Engines like these are the unsung workhorse of the modern world.
0:53:55 > 0:53:56ALARM WAILS
0:53:56 > 0:53:59There's alarms going off everywhere.
0:54:00 > 0:54:05'Ultra-large marine diesels have transformed modern shipping.'
0:54:05 > 0:54:07These vessels are so vast,
0:54:07 > 0:54:11they look like they'd be painfully slow, but not true.
0:54:11 > 0:54:16Today, the largest diesel-powered cargo ships
0:54:16 > 0:54:20rock along at a staggering 50km an hour.
0:54:20 > 0:54:24And that, with the greatest fuel efficiency
0:54:24 > 0:54:26of any engine in the world.
0:54:26 > 0:54:3250km an hour, is fast enough to water-ski behind.
0:54:34 > 0:54:41The very first container ship in 1956 could handle 210 containers.
0:54:41 > 0:54:45The increasing power of marine diesels has allowed
0:54:45 > 0:54:49a 50-fold increase in the size of these vessels.
0:54:49 > 0:54:54Today, the largest can handle over 15,000 containers.
0:54:54 > 0:54:56If you loaded all those on a train,
0:54:56 > 0:55:00it would be 91km long.
0:55:00 > 0:55:03'The impact on shipping costs of all this
0:55:03 > 0:55:06'has turned global economics on its head.'
0:55:08 > 0:55:09The incredible power
0:55:09 > 0:55:13and efficiency of 21st-century diesel-powered ships
0:55:13 > 0:55:18means that it's cheaper to ship something from Shanghai to Felixstowe
0:55:18 > 0:55:24than it is to deliver it from your local shop to your house.
0:55:24 > 0:55:31'Around 99% of modern cargo ships of all sizes use diesel engines,
0:55:31 > 0:55:34'forming the backbone of a diesel-powered
0:55:34 > 0:55:36'network of global trade.'
0:55:36 > 0:55:40Imagine a crop grown in Africa or Latin America
0:55:40 > 0:55:45that's irrigated by a diesel-powered pump
0:55:45 > 0:55:49and it's cultivated by diesel-powered tractors.
0:55:51 > 0:55:55When the crop's harvested, it's taken to a canning factory,
0:55:55 > 0:55:58probably in a diesel-powered truck,
0:55:58 > 0:56:01and the canning factory is powered by a diesel generator.
0:56:03 > 0:56:06The cans are then put in containers like these
0:56:06 > 0:56:10and taken by road or rail, diesel, again, to a port,
0:56:10 > 0:56:13where a diesel crane loads them
0:56:13 > 0:56:17onto a diesel-powered ship that brings them here.
0:56:17 > 0:56:22When they arrive, more diesel-powered cranes unload the containers
0:56:22 > 0:56:25and put them on more diesel-powered lorries
0:56:25 > 0:56:29and then they're distributed around the country on more trains,
0:56:29 > 0:56:33trucks and vans, all powered by diesel.
0:56:34 > 0:56:37The true extent of the diesel engine's role
0:56:37 > 0:56:43in the modern globalised economy is simply astonishing.
0:56:43 > 0:56:47Measured in the distance that goods have to travel from their manufacture
0:56:47 > 0:56:53to their point of sale, about 94% of global trade is diesel-powered.
0:56:55 > 0:57:01Today, the diesel is the most indispensible engine in the world.
0:57:01 > 0:57:07It's not just powering cargo ships, but pleasure boats and ferries, too.
0:57:07 > 0:57:12Not just agricultural machinery, but construction machines, as well.
0:57:12 > 0:57:15Not just almost all commercial vehicles,
0:57:15 > 0:57:18but almost all military vehicles.
0:57:18 > 0:57:24The only notable area of transport it has not touched is aviation.
0:57:24 > 0:57:26But like all engines that burn fossil fuels,
0:57:26 > 0:57:31the diesel's future is unclear.
0:57:31 > 0:57:34Having promoted it for its environmental friendliness,
0:57:34 > 0:57:36we've now learned it emits gases
0:57:36 > 0:57:40and particulates that are harmful to human health.
0:57:40 > 0:57:43Rudolf Diesel would, no doubt, be reminding us
0:57:43 > 0:57:46how his original engines ran on peanut oil,
0:57:46 > 0:57:50and suggesting that biofuels could be a way forward.
0:57:50 > 0:57:52But whatever the diesel's fate,
0:57:52 > 0:57:56its importance to the modern world is clear.
0:57:56 > 0:58:00Whether you like diesel engines or you loathe them,
0:58:00 > 0:58:03I hope I've managed to convince you that the way we live
0:58:03 > 0:58:06today would be very, very different without them.
0:58:06 > 0:58:10Just as steam engines powered the Industrial Revolution,
0:58:10 > 0:58:13the diesel engine has been the driving force
0:58:13 > 0:58:17behind the globalisation of our 21st-century world.
0:58:17 > 0:58:21Now, whatever the future for the compression-ignition engine,
0:58:21 > 0:58:28I for one think it's high time we doffed our caps to Rudolf Diesel
0:58:28 > 0:58:34and gave his simple, but brilliant invention a little more love.