Mission X_2of4_The Power of The Propeller
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00:00Today, giant ships transport almost 90% of the world's freight across the oceans.
00:07Their ability to ship massive cargoes at speed owes a great deal to the innovative work of a 19th century inventor.
00:15This is the story of Josef Ressel, whose vision led to the development of the modern-day propeller, revolutionizing shipping forever.
00:25He was a hard-working Austrian forester who saw a way to improve on the paddle steamers of his day by fitting ships with a completely new propulsion mechanism.
00:36He was filled with a desire to push the boundaries of technology.
00:41Ressel was too good-natured. He wants the whole world to benefit from the fruits of his invention.
00:47But he was no businessman, and powerful rivals would betray him.
00:51When you look at a line of inventions like that, you say that the persons at the beginning of the line were perhaps not so commercially smart, and the ones at the end were the good businessmen.
01:02Despite constant setbacks, he never stopped believing his idea could change the face of shipping.
01:08The forester's influence will be felt well into the future, forming the basis of ships' propulsion today.
01:15This is Josef Ressel and the invention of the propeller.
02:15From Asia to Europe, Africa to South America, shipping lines wind their way through the oceans of the world.
02:23Every year, the volume of trade grows, and with it, the size of ships.
02:29The very latest vessels can carry up to 11,000 containers, and are propelled through the sea by more than 100,000 horsepower of thrust, using a single gigantic propeller.
02:43This wouldn't be possible if it weren't for the development of the screw propeller over 150 years ago.
02:51It's October 1829, and Josef Ressel's great vision is finally about to become a reality.
02:59Tomorrow, the Civetta will set sail before the eyes of a curious Trieste public, propelled by a new kind of spiral he's developed.
03:10It's been a long and arduous journey to reach this landmark.
03:16His quest began with his transfer to the port city of Trieste eight years previously.
03:25Back then, these coastal forests of Istria used to belong to the Austrian Empire.
03:32The young Josef Ressel is responsible for huge areas of forest, a rich source of shipbuilding wood for the Austrian fleet.
03:42These forests are maintained to provide the specialized cuts of wood needed to build the large ships of the day.
03:50Curved pieces of oak are in high demand for use as ribs and fittings.
03:56These naturally occurring shapes are sought out and directly selected for this purpose.
04:05Ressel's duties include calculating the stock and selecting the woods required, as well as ensuring their timely delivery to Venice.
04:14But his passion lies with technology.
04:17He's always suggesting improvements, such as better methods of calculation and new measuring instruments.
04:25But his superiors often view him as nothing more than disruptive.
04:33He was a man who constantly had new projects in mind, who was constantly working on new inventions.
04:41And here in Trieste, the sea put new ideas in his head.
04:48Ressel and his family have now been living in the port of Trieste in the Adriatic for several years.
04:55Inspired by the proximity of the sea, Josef is increasingly occupied with the problems associated with navigation and shipping.
05:06Ressel met his wife, Jakobina, on a business trip through Istria.
05:11They were married just a few weeks later. Soon after, their first child was born.
05:17In the little spare time he has, Ressel works on his inventions.
05:21He even holds the patent for a new type of measuring instrument, but it fails to bring in any money.
05:28With his annual salary of 800 florins, he just about manages to support his family.
05:34He tries to reassure his wife, Jakobina, who worries about meeting even their most basic expenses.
05:41But this time, Trieste is linked to Venice by paddle steam.
05:49Passengers must endure a 19-hour voyage on board.
05:56Deafening noise and acrid smoke turn the passage into a tortuous ordeal.
06:03An English businessman called William Morgan holds the helm.
06:07The English businessman, called William Morgan, holds the exclusive rights to operate the paddle steamer on this lucrative route.
06:15Almost daily, passengers complain. Some even ask for compensation.
06:20But Morgan arrogantly advises them to make the slow sailing ship crossing instead.
06:26He was to become Ressel's bitter rival.
06:30Morgan ran a monopoly on the shipping line between Trieste and Venice.
06:39These towns were the richest ports of the upper Adriatic.
06:51At the time, steamships were still very small and expensive.
06:56Until around 1850, only the post, valuable goods, and very wealthy noblemen were transported by steamship.
07:11Very few paddle steamers were in operation at the time, and since they weren't huge,
07:17they could only be operated by a small number of people.
07:21Only a few paddle steamers were in operation at the time,
07:25and since they weren't suitable for high seas, they were forced to remain near the coastline.
07:30During a heavy storm, the paddle wheels would repeatedly rise out of the water and rotate in the air.
07:37But even in the best conditions, a paddle steamer's propulsion is very ineffective.
07:44Half of the wheel rotates above the water's surface,
07:47and the plunging paddles tend to force the ship upwards when inserted.
07:53Only a sixth of the wheel's rotation actually pushes the water backwards, producing any forward momentum.
08:03One evening in 1825, a couple of his friends are guests in the Ressel house.
08:09Josef has just returned from a business trip to Venice by paddle steamer.
08:13He's appalled by how unsuitable this method of propulsion is for sea travel.
08:19He realises just how exposed to damage the massive paddle wheel housing is during docking manoeuvres,
08:26and they would also pose an easy target for guns during a war.
08:31He believes that the time is right for an improved propulsion method for ships.
08:37Suddenly, the corkscrew sparks a flash of inspiration.
08:42Just as it bores into the cork, could a screw not also bore into water?
08:48If mounted to the front of the ship, the screw could pull the ship along behind it.
08:54A radical idea has formed in Josef Ressel's mind.
08:58He's one that won't let go of him for the rest of his life.
09:01In a European shipyard, a container ship of unparalleled size is being designed.
09:07Calculating the necessary dimensions of the propeller poses many problems.
09:16The design of a propeller is almost comparable to the work of a fashion designer.
09:22The design of a propeller is almost comparable to the work of a fashion designer.
09:26The design of a propeller is almost comparable to the work of a fashion designer.
09:32The propeller has to be adjusted to work with the engine requirements,
09:37but it also has to supply what the ship demands of the propeller.
09:42Adapting it to both demands is very delicate precision work.
09:48The propeller will have a diameter of more than nine meters.
09:53That's almost four stories high.
09:56Many experts doubt that the necessary 100,000 horsepower can be generated with only a single propeller.
10:04But the ship's owners have requested the single-propeller solution
10:08because it's simpler, more effective and needs less maintenance.
10:11Even the most experienced of the designers are entering uncharted territory.
10:18Josef Ressel had been a student at the Technical University of Vienna,
10:23studying natural history, chemistry, mechanics and hydraulics.
10:28When his father lost his job, the family became impoverished,
10:33forcing Ressel to leave and become a forester.
10:36But his fascination with technology remained.
10:38It's likely that he already knew that moving water with a screw was possible.
10:44Over 2,000 years earlier, Archimedes had already developed what is now known as the Archimedean screw,
10:52which was widely used for irrigating crop fields.
10:56Ressel must have known that the principle had been rediscovered a few decades before
11:01and was put to work in Holland to drain entire swathes of land.
11:05If fitted to a ship, a small Archimedean screw should be able to accelerate water
11:12and give the ship forward momentum.
11:16Having found his answer, Ressel plans to patent his invention,
11:20but can't proceed without funding.
11:23He desperately needs the financial backing.
11:27He tries to find interest among influential Trieste businessmen.
11:30The money is needed to build a metal prototype of the screw.
11:36His first meeting is with the well-known shipowner, Morgan.
11:41Morgan carefully studies the blueprints,
11:44but he'd be a fool to threaten the success of his own paddle steamer
11:48by financing a new propulsion mechanism and declines.
11:52Ressel is stunned.
11:56Why couldn't he see the enormous advantages of propeller-driven propulsion?
12:02Morgan won't be the last to disappoint Ressel.
12:07Everywhere, he encounters derision and rejection.
12:11Soon, he's the laughingstock of Trieste.
12:14He'll be the first man in the world to build a propeller-driven propeller.
12:18But others around the world were working on the same concept.
12:24In the 18th century, there were already experiments by Brahma,
12:28Littleton and Shorter.
12:30The most important one was Stevens,
12:33who managed to accelerate a ship to a speed of four knots
12:37with a windmill-like screw and a steam engine by watt in 1804.
12:42Leonardo da Vinci had already created plans for a screw-propulsion system.
12:47At the end of the 17th century,
12:50the English mathematician Hooke designed windmill-like blades to propel a ship.
12:55And in the 18th century, the American engineer Fulton
12:59planned to propel his U-boat Nautilus using a screw.
13:03In the 18th century, the American engineer Fulton
13:07planned to propel his U-boat Nautilus using a screw.
13:12Ressel prepares the documents for his patent.
13:18His wife, Jakobina, is worried about the expense.
13:22The registration alone costs 26 florins.
13:26That's nearly half a month's salary.
13:30Josef Ressel has forged a friendship with the shipbuilder Zanon,
13:34who's working at a Trieste shipyard.
13:36Zanon tries to encourage his boss to back Ressel without success.
13:41One day, in the spring of 1826,
13:44two Trieste merchants appear at the shipyard,
13:47having learned of Ressel's plans.
13:49Eager to show off his invention to the two men,
13:52Ressel explains, in great detail,
13:55the workings of his revolutionary propeller.
13:58Impressed by what they're shown,
14:00the businessmen put up 60 florins to finance his work on the prototype.
14:05They will also provide a boat on which Ressel is able to conduct his tests.
14:10He has no idea of the future impact his project will have
14:15as it finally gets off the ground.
14:18In order to propel a fully loaded container ship at over 30 miles per hour,
14:24an incredible amount of power is needed.
14:28The massive blades cut through the water at up to 95 miles per hour.
14:34This creates bubbles of steam, a process known as cavitation.
14:42Should these bubbles implode, damaging amounts of energy are released.
14:48The destruction through cavitation is so unbelievably great
14:54that deep furrows and trenches are beaten into the propeller blades,
15:00rendering it completely useless.
15:03Controlling cavitation is one of the major challenges for the designer.
15:08Before the propeller goes into production,
15:10prototypes of both the ship and the propeller are tested.
15:16The engineers analyze their behavior in water,
15:19to determine whether the ship is ready for the next stage of production.
15:24The ship is then loaded onto a boat,
15:27and the propeller is tested.
15:30The engineers analyze their behavior in water,
15:33which will tell them if the designer has managed to create the perfect profile.
15:39But no matter how rigorous the testing process,
15:42the propeller needs at least six months of real-world use
15:46before they can be sure it's up to the task.
15:51Only this will prove if it can cope with the enormous forces involved
15:56and can keep cavitation under control at every speed.
16:02But in Russell's time, this phenomenon had yet to be discovered.
16:11In February 1827, the blacksmith Franz Hermann from Trieste delivers the screw.
16:19It's been cast from a bronze alloy and has a diameter of 45 centimeters.
16:29Russell writes,
16:30the most appropriate place to install the wheel is at the front.
16:34It isn't advisable at the rear end,
16:36because the current produced by the moving ship could interfere with its effectiveness.
16:41At the position where the spindle penetrates the ship's hull,
16:44it has to be conical, so it can be waterproof.
16:55To ensure the effectiveness of the screw,
16:57it's positioned to be completely below the surface of the water.
17:03The screw is then screwed to the ship's hull.
17:06To ensure the effectiveness of the screw,
17:08it's positioned to be completely below the surface of the water.
17:28Russell notes,
17:29in the interests of caution,
17:31it's a good idea to install an iron cage in front of the wheel,
17:35so that during high waves, the screw doesn't suffer such a harsh, detrimental hit.
17:46Ideally, Russell would like a steam engine to drive the screw,
17:50but the prototype will have to rely on human power.
17:54In the modern age,
17:56the global shipping industry has undergone an unprecedented boom.
18:01As ships grow to meet the ever-growing demand,
18:04so too do the propellers.
18:11130 tons of copper, nickel and aluminium are being melted down
18:17in order to cast the largest propeller in the world
18:20at Mecklenburger Metallgoss in Germany.
18:26The company is the world leader in its field.
18:30Here, propellers are cast for giant container ships,
18:34cruise liners and navy vessels.
18:39But even here,
18:40a propeller of 9 meters in diameter is something out of the ordinary.
18:46It requires a high degree of expertise
18:48to ensure that no bubbles are formed in the molten metal at this stage.
18:59The casting takes just 20 minutes,
19:02but they'll only know if it's been successful once the metal's cooled down,
19:06which can take a whole week.
19:11Thousands of ships are on long voyages every single day,
19:15powered by propellers of varying dimensions.
19:18But 150 years ago, this was inconceivable.
19:29Josef Ressel has longed for his big day to arrive.
19:33Two months ago, he received his patent.
19:36It will now be put to the test.
19:38But nobody is quite sure if it'll work.
19:46A complaint was later made to the police
19:48that the boat makes a hellish noise and scares the fish away.
19:55But Ressel's bronze propeller works
19:57and pulls the boat steadily forwards.
20:07Passers-by watch as the boat moves through the water,
20:10seemingly driven by a ghostly power.
20:14Yet not everyone is happy with the new development.
20:19Maybe Morgan has underestimated Ressel's drive to succeed.
20:23It seems the young inventor could become a serious threat to his business.
20:30This is a breakthrough.
20:32Ressel feels he's on the road to success.
20:36He hopes his ship's screw will bring him not only fame, but also fortune.
20:45Soon after, another wealthy Trieste businessman,
20:48Ottavio Fontana, makes him a tempting offer.
20:53He wants to finance a passenger ship driven by steam engine and propeller.
20:59He suggests a profit share if the inventor transfers the patent to him.
21:05Josef Ressel agrees.
21:10They immediately set about publicizing their plan
21:13to run the new service between Trieste and Venice.
21:17Immediately afterwards, in June of the same year,
21:21Morgan issues an appeal.
21:24He doesn't want Ressel to start operating a propeller-driven ship
21:28on the route Trieste to Venice under any circumstances.
21:35Morgan is incensed.
21:37He has the exclusive rights to operate this lucrative route with his paddle steamer.
21:42He'll stop Ressel by any means necessary.
21:49Ressel's on another business trip in Istria.
21:52He's busy overseeing the repair of drainage ditches
21:55when he receives devastating news.
21:59His wife is seriously ill.
22:02Immediately he returns home to be by her side.
22:06Tragically, the doctors can do nothing to save Jacobina.
22:10She dies, most probably of tuberculosis.
22:15Suddenly, Ressel is left to bring up his three children on his own.
22:27Josef Ressel was going through a period of depression.
22:31A difficult time began for Josef Ressel.
22:35Only a short time later, his little daughter Paolina also dies.
22:41Now he was alone with his two sons.
22:48He had debts from the doctor's bills, medication, and the hospital.
22:55To top it all, he had to pay a huge sum of money.
23:01He also got into trouble with his superiors.
23:08There are more setbacks for Ressel.
23:10The plans for his shipping company hit trouble with the authorities.
23:14The police raid his home and claim that he didn't go through the proper channels.
23:19Having heard about the scandal, Ressel's boss is outraged
23:22and orders him to stop bringing his department into disrepute.
23:27Not long after, the royal court issues a decree
23:30that prohibits Ressel from operating his shipping line,
23:33referring to Morgan's exclusive rights.
23:37Ressel must get this decision overturned,
23:39otherwise Fontana will withdraw his financial backing.
23:43He sets off for Vienna.
23:51His intention is to persuade the head of the royal court
23:54His intention is to persuade the head of the royal chancellery, Count Zurau,
23:58that Morgan's rights only relate to the paddle steamer
24:01and not to the screw-driven steamer.
24:05Eventually, Count Zurau agrees and allows him to continue.
24:09But on one condition.
24:11The steam engine must be built here in Austria
24:14by the company owned by Baron Baldacci.
24:17Ressel would have preferred one of the new English steam engines
24:20with their reliable reputations.
24:23But seeing no other option, he agrees.
24:26It was something he would later regret.
24:33Over 150 years later,
24:35the designers have reached new levels of achievement.
24:38The propeller is taken out of its cast.
24:41With a record-breaking diameter,
24:44it will power one of the mightiest container ships in the world.
24:53We can only build on what we've done previously.
24:56In this way, one propeller propulsion has evolved step by step
25:00up to the dimensions we work with today.
25:03Over 100,000 horsepower on a single propeller
25:07is a huge amount of power.
25:10Over 100,000 horsepower on a single propeller
25:14is an unbelievable number.
25:21The casting of the massive propeller has been a success.
25:25Now every detail will be checked against the designer's specifications.
25:30The propeller is measured to the millimeter
25:32and then refined by a huge computer-controlled milling machine.
25:37Robots take several days to shape the perfect profile.
25:43The bronze is resistant to seawater,
25:46yet its malleability makes it easy to work with,
25:49and in the event of an emergency,
25:51much easier to repair than a propeller made of steel or iron.
25:57The final finishing cannot be done by robot.
26:00This must be carried out by hand.
26:04Everything depends on the precision of the blade profile.
26:08Any defects could cause vibrations in the propeller as it rotates.
26:13Only with this high level of accuracy
26:16can they guarantee the durability of the mechanism.
26:20Such technical ingenuity was way beyond anyone's imagination
26:24in Josef Ressel's time.
26:27In the autumn of 1828,
26:30a man named Louis Bauer comes to Trieste and looks up Ressel.
26:35Bauer introduces himself as an agent.
26:38He is here on behalf of some Parisian business people
26:42who claim to be very interested in his invention.
26:50Ressel was too good-natured.
26:54He wanted the whole world to benefit from the fruits of his invention.
27:03He was a disaster when it came to business.
27:08He gave all of his plans to this man, Louis Bauer,
27:13without knowing him, without a contract, and without any security.
27:19He gave him everything he had.
27:23Without question, Ressel immediately gathers his plans
27:27and provides detailed instruction of how the propeller should be constructed.
27:33Ressel is keen to show off his work,
27:36and in his naivety hands the stranger his plans to read through at leisure.
27:43He also offers to travel all the way to Paris should any problems arise.
27:55In the winter of 1828, building begins on the 20-metre-long prototype.
28:01The ship, costing around 30,000 florins, will be named the Chibis.
28:07The ship, costing around 30,000 florins, will be named the Chiveta.
28:13It will be powered by a six-horsepower steam engine,
28:17which in Ressel's view is far too small for a ship of this size.
28:23To reassure his financier Fontana, the Chiveta will also have masts,
28:28so that if the screw propulsion fails, she can still be used as a coastal sailing ship.
28:35March the following year, and the Chiveta's propeller is ready.
28:40It's 1.5 metres in diameter and cast in copper alloy.
28:50Ressel is pleased with the result.
28:53He feels closer than ever to his goal.
28:56But unfortunately, the steam engine is still not ready.
29:02This time, the propeller will not be mounted at the front of the ship,
29:06but at the rear, between the hull and the rudder.
29:16Ressel initially had the propeller at the front.
29:20But he left this arrangement behind,
29:23when he realised that the work of the propeller added resistance to the ship's hull.
29:32A propeller fitted to the bow of a ship sucks the water in and accelerates it backwards,
29:38increasing the counter-current on the ship's hull.
29:41But if it's fitted at the rear, the increased counter-current boosts the effectiveness of the rudder.
29:47It remains the ideal position to this day.
29:53In April 29, Ressel travels to Paris.
29:57The agent Louis Bauer is pressuring him to introduce his invention to the French investors.
30:05Fontana supports the endeavour,
30:08seeing it as a chance to make money from the patent,
30:11whilst awaiting delivery of the steam engine in Trieste.
30:17Although Ressel hates the discomfort of several days' travel,
30:21he sets off on his journey full of hope.
30:28Ressel demonstrates his screw propulsion on the River Seine.
30:33The press writes enthusiastically about it, but doesn't mention Ressel by name.
30:40The French business consortium takes all the credit,
30:44having deviously patented his designs in France months ago.
30:48And to make matters worse, they refuse to give Ressel any financial reward whatsoever.
30:58Paris was a disaster.
31:02Joseph was left completely penniless, and Fontana refused to send any money.
31:08Joseph tries to get through a day at a time, and can't pay for his hotel,
31:14doesn't have any money for day-to-day expenses.
31:21Without money, Ressel has no way of getting back to Trieste.
31:25In his desperation, he goes to the Parisian Stock Exchange,
31:29where, at a particular spot, the Trieste businessmen meet.
31:33He hopes to find a way to get back home.
31:36Louis Bauer will later inform Ressel that his business partners are marketing his idea
31:41as their own invention in France and England.
31:45A patent application for a ship's propeller is announced in London.
31:50The drawing is almost identical to Ressel's original.
31:54The text mentions that the idea was generated by someone overseas,
31:59but makes no mention of Ressel.
32:04Two months later, Joseph Ressel arrives back in Trieste,
32:08only to hear that Fontana is thinking of withdrawing from the project.
32:15At the shipyard, they've waited months for the delivery of the steam engine from Styria.
32:21It finally arrives in early summer,
32:24taking the mechanics another three months to assemble it.
32:28But initial test runs show that it's unreliable.
32:32To make matters worse, Ressel's opponent, Morgan, is expanding his operation.
32:42At that time, there wasn't a businessman left in Trieste
32:46who still believed in the ship's propeller.
32:50The only way to make money with it was the route Trieste to Venice, Venice to Trieste.
32:59But this line was more firmly in Morgan's hand than ever.
33:04And Morgan had already ordered a second steamship,
33:08much quicker and much more comfortable, but still a paddle steamer.
33:14Although Ressel and Fontana had once been the talk of the town,
33:18the fishermen of Trieste only take a passing notice of the events of October 1829.
33:27The long-awaited test run of the Civetta is imminent.
33:31Franz Hermann, the Scrooge's blacksmith, is servicing the steam engine himself.
33:37Ressel and Fontana are relieved
33:39as the Civetta slowly gathers speed and leaves the port.
33:43So far this morning, everything has gone according to plan.
33:47The Scrooge is working.
33:49The Civetta moves out into the open sea at a steady speed.
33:56Ressel is overjoyed.
33:58This could be the beginning of a whole new era.
34:02A number of guests are on board to witness the success,
34:05including the port captain and the chief of police.
34:09Now Ressel's doubters will have to admit they were wrong.
34:13Even Fontana is in an excellent mood
34:16in the belief that finally his investment is showing promise.
34:22Ressel is busy exploring the port,
34:24but he has no time to waste.
34:27His investment is showing promise.
34:31Ressel is busy explaining how his mysterious bronze screw works
34:35to a sceptical university professor and his wife
34:39when things start to go horribly wrong.
34:43Suddenly, steam emerges from the engine room.
34:50Hermann tries desperately to take the pressure off the boiler.
34:54It's the unreliable steam engine that's causing problems.
34:58Prior to today, they'd already identified more than 13 defects,
35:03and now a steam pipe has burst.
35:06It couldn't have happened at a worse time.
35:16Hermann and Ressel desperately try to seal the leak.
35:20It's hopeless.
35:22They have to let the machine cool down to have a chance of repairing it.
35:32Ressel estimates the repairs will take two hours,
35:36but the chief of police puts a stop to any further attempts.
35:41Ressel's outraged.
35:43The engine has let him down, not the screw,
35:46but his appeals fall on deaf ears.
35:49The steam engine had run flawlessly for only ten minutes,
35:53during which the Civetta managed to travel half a nautical mile
35:57powered by the propeller.
35:59Now she lies drifting helplessly in the bay.
36:04This comes as good news to Morgan.
36:07His business will not be affected,
36:10and Fontana will use the disastrous test run
36:13to distance himself completely from the project.
36:20At the Institute for Marine Research at the University of Trieste,
36:24scientists have created a replica of the Civetta's propeller.
36:29In the cavitation tunnel,
36:31they want to find out how Ressel's propeller would have performed.
36:35They simulate the rotational speed of the six-horsepower steam engine,
36:40exactly how effective was the screw.
36:44This scale model of the Civetta is based on the same measurements
36:48the same weight and the same water displacement as Ressel's original.
36:53The miniature Civetta is put to the test.
36:57How fast will the ship be?
37:00Eyewitnesses of the fateful journey
37:02said that the Civetta sailed a distance of around 800 metres
37:06at about 4 to 5 knots.
37:09The experiment shows beyond doubt
37:11that the Civetta could easily have travelled at double the speed.
37:16What stopped this from happening
37:18was the inferior steam engine, not the propeller.
37:25The propeller for one of the biggest container ships on Earth is ready.
37:30It is the first of six, ordered by a Danish shipyard.
37:34Before its delivery, the client will not only measure the propeller
37:38and check the density of the materials,
37:41they also wish to install and test it.
37:46To do this, the shaft on which the propeller will sit
37:50has been transported from the shipyard to Mecklenburg.
37:55Using hydraulics, the hub is expanded by several millimetres
38:00and pushed onto the conical shaft.
38:03But they can only be certain it will function correctly
38:06after its first voyage.
38:10No matter how many simulations it's put through,
38:13only testing in the open sea will guarantee
38:16that the propeller has been designed to the exact requirements of the ship's hull
38:21and tell them if cavitation and vibration are under control at every speed.
38:29The real proving ground for a ship has always been the ocean.
38:36After the disastrous outing of the Civetta,
38:39in full view of the Trieste public,
38:42Ressel is hoping for another trial run.
38:45Fontana has lost all interest in the project,
38:48but still holds the patent.
38:50Ressel demands he should fulfil his side of the contract.
38:53You can keep the contract, and I my money,
38:56answers Fontana as he shuts the door on him.
39:01Ressel is infuriated.
39:03He'll not let him get away with this without a fight.
39:07Despite Fontana's standing as a powerful businessman,
39:10Joseph Ressel decides to take him to court.
39:16The State Archives in Trieste still holds the documents.
39:21The case ran for years through three judicial levels.
39:25But before a judgment could be made, Fontana died.
39:31His sons offer a compromise, which Ressel grudgingly accepts,
39:35giving him around 3,500 florins as compensation,
39:39hardly enough to cover his costs.
39:43Now 43, Ressel has been promoted to provisional head forester,
39:48and transferred with his family to Montona,
39:51a little village in the middle of Istria.
39:54By then, Joseph had married his long-serving children's nanny,
39:58Teresa Castellec, with whom he'd have another seven children.
40:02But unfortunately, his salary was cut from 800 to only 600 florins.
40:11The Venetians were the first in the world
40:14to put a methodical forestry program into action,
40:17and it was established here, in Montona.
40:22When Ressel takes over responsibility for the marine forests,
40:26the woods in the valleys are in a sorry state.
40:29The river Chieto regularly floods,
40:32and the mud left behind kills large numbers of oak and elm trees.
40:37The workmen live under terrible conditions in the malaria-infested area.
40:43Ressel goes about repairing drainage ditches and infrastructure.
40:48He provides reasonable living quarters for his co-workers,
40:52on higher ground, away from the swamps.
40:55Ressel is sympathetic towards the local population's situation.
41:00Offences against forest laws, such as the theft of wood,
41:04are widespread among the poor, resulting in severe punishment.
41:09But Ressel allows them to continue.
41:12He explains to his co-workers and superiors
41:15that he'd rather they take the thin waste wood,
41:18and not the valuable trunks.
41:21Tirelessly, he tries to convince his employers
41:24that the reforestation of the karst area is the most pressing project.
41:29But for years, his pleas fall on deaf ears.
41:40Ressel is a man of his word.
41:43He's a man of his word.
41:46He's a man of his word.
41:49At long last, his persistence pays off.
41:53Josef Ressel initiates the replanting of large areas of land throughout Istria,
41:58right down to the coast of Dalmatia.
42:01He even undertakes trials on the island of Kruk.
42:08Throughout this time, Ressel is still an inventor,
42:11with a prolific output of new ideas.
42:15He improves the plough used by the rural population,
42:18making it easier to steer.
42:21He develops a steam wagon designed to drive on the road.
42:27He also invents a rolling mill incorporating cylinder chains,
42:31and a friction-free bearing,
42:34the ball bearing.
42:39In 1843, Ressel, who by now has entered the naval service,
42:43is transferred to Venice,
42:45where the Austrian navy's ships are constructed.
42:50Over two years, he learns every detail of shipbuilding,
42:53in order to optimise the supply of specialised cuts of wood from the forests.
43:00The inventor in Ressel is, once again, inspired by his new role.
43:06He develops a method of bending wood over steam,
43:09and suggests the use of iron as a material for ships' keels and ribs.
43:19But the shipbuilders at the Arsenal of Venice dismiss his radical suggestions.
43:24They prefer to stick with their traditional methods.
43:33Once again, Ressel is far ahead of his time.
43:37But overseas, a change is in the air,
43:40and things are moving at a much faster pace.
43:45With its technological advancement,
43:47England has overtaken the young industries on the continent.
43:55The English don't just build more effective steam engines.
43:58The Admiralty is actively encouraging innovations in shipbuilding.
44:03At a shipyard in Bristol,
44:05the first vessel made entirely from iron is under construction.
44:09Its name is the SS Great Britain.
44:12The ship's builder is the legendary engineer Isambard Kingdom Brunel.
44:18He will pioneer the breakthrough of the ship's propeller.
44:25Meanwhile, an English farmer has been experimenting for years
44:29with an Archimedean screw.
44:32His name is Francis Pettit-Smith.
44:36When the screw accidentally breaks during a test run,
44:40he finds that the ship sails even faster with what remains.
44:44This fires his imagination.
44:48The SS Great Britain, a luxurious passenger ship,
44:52is designed to cross the Atlantic in record-breaking time.
44:56Initially, the plan was to build a paddle steamer,
44:59but during her construction, Brunel opts for a different solution.
45:04In the Bristol shipyard, Smith is asked to install a propeller instead.
45:09The Archimedean screw is reduced to individual blades.
45:16Charles Kuparov made much the same design two years later.
45:20I don't know what his...
45:23background is and whether or not he may have copied designs from Ressel.
45:27There's no real evidence one way or the other.
45:30But eight years after that,
45:32then Francis Pettit-Smith comes up with a very similar design again.
45:37Who can tell?
45:39When you look at a line of inventions like that,
45:42you say that the persons at the beginning of the line
45:45were perhaps not so commercially smart,
45:47and the ones at the end were the good businessmen.
45:50Despite the many knockbacks,
45:52Joseph Ressel never gives up on his unfinished idea.
45:55In the following years, he continues to develop his propeller,
45:59working through many different variations.
46:02Then he hits upon a brilliant idea.
46:05It should be possible to make the propeller and its thrust steerable.
46:09A ship would be much more manoeuvrable,
46:12and there'd be no need to have a separate rudder.
46:15But this innovation won't be properly developed
46:18until many years later,
46:20as part of the so-called pod propulsion system,
46:24which suspends a propeller from a rotating gondola.
46:30The principle of pod propulsion
46:33was originated by two German engineers in 1955.
46:38The propulsion mechanism is surrounded
46:41by an aerodynamic gondola casing,
46:44which can be rotated through a full 360 degrees.
46:53Large generators on board the vessel
46:56provide electrical power to the pull propeller,
46:59which is powered by an electric motor.
47:02Since the propulsion mechanism is independent
47:05of the location of the power source,
47:08the propellers are free to be mounted in their optimum position.
47:18These rotatable pods allow ships to be extremely manoeuvrable
47:22and make rudder mechanisms much easier to operate.
47:26These rotatable pods allow ships to be extremely manoeuvrable
47:30and make rudder mechanisms superfluous.
47:34Pod propulsion has many advantages over more traditional systems.
47:38It enables the water to gain easy access to the propellers,
47:42which means greater efficiency and uses less fuel.
47:49Cruise ships in particular use this method of propulsion,
47:53including the Freedom of the Seas,
47:56the biggest passenger ship in the world.
48:00It isn't until docking manoeuvres
48:02that the immense advantages become apparent.
48:05That's when the pods are directed sideways,
48:08smoothly pulling the ship to the pier,
48:11meaning there's no need to be towed into harbour.
48:17We brought the Freedom of the Seas out.
48:19I was able to put my azipod at 90 degrees
48:22and brought her straight out.
48:24She did not fall to the south at all.
48:26Once we had completed the manoeuvre,
48:28there was a captain on a tugboat
48:30which was standing by to take another cruise ship out.
48:32He commented on the radio to our pilot,
48:34he says, well, now he's seen it all.
48:36He's seen the biggest ship in the world
48:38go out in a very strong ebb from the Hudson
48:41at three and a half knots
48:43and not need the assistance of tugboats.
48:45So he was amazed and I think it's pretty safe to say
48:48he was pretty disappointed too.
48:53Another new propulsion mechanism was patented in 1927
48:58by a young Austrian inventor called Ernst Schneider.
49:09Today, the Voigt-Schneider propeller
49:11is mainly used by emergency boats, tugboats
49:14and ships that have to manoeuvre in the smallest spaces.
49:23Vertical blades, fixed to a rotating plate,
49:27propel the ship by individually changing their angle of attack.
49:35The ship can be turned very quickly and precisely
49:38by changing the direction of thrust.
49:42Ressel's ideas were certainly ahead of his time.
49:47In September 1852,
49:49Ressel spots something interesting in a newspaper.
49:52The English Admiralty has announced that
49:55whoever can demonstrate that they were the first
49:58to successfully propel a steamship
50:00with an Archimedean screw
50:02will receive £20,000.
50:05Ressel gathers hope
50:07and sends his original patent documents.
50:10In vain, he waits for a response.
50:13Five years pass.
50:15Again and again, Austrian diplomats
50:18press the English Admiralty for information.
50:23Eventually, a succinct reply arrives
50:26stating that the documents must have been lost.
50:30In fact, the decision has already been made
50:33to divide the sum between five English ships.
50:36Once again, Ressel is left empty-handed.
50:43With his 59 years,
50:45Josef didn't feel at all old.
50:47He was in good health,
50:49but his spirit had been broken.
50:52He'd suffered injustice, disappointment,
50:56misunderstandings, money worries.
50:59His spirit was ruined.
51:02In despair, Ressel contacts the Archduke Maximilian,
51:06who has just taken up residence in Trieste
51:09where he's having the Miramar Castle built on the coast.
51:14Ressel is designing the park and forest behind the castle
51:18and implores the Archduke to do everything within his power
51:21to get him to agree to the deal.
51:23He's not satisfied.
51:25He's not satisfied.
51:27He's not satisfied.
51:30He's not satisfied.
51:32He's not satisfied.
51:34He has to do everything within his power
51:37to get him justice at last.
51:39But the Archduke is unable to help.
51:46In the autumn of 1857,
51:48Ressel goes on a business trip
51:50from which he will never return.
51:55On the evening of the 3rd October,
51:57Just a few days later, Josef Ressel dies,
52:01most likely as a result of malaria or typhoid fever.
52:06Just a few hundred meters from the place where he died,
52:10in the cemetery of Ljubljana, stands Josef Ressel's headstone.
52:17One of his last letters was addressed to the Archduke Maximilian.
52:24The propeller is an Austrian, he writes,
52:28and it must enter history as such.