Dornier Do X

Dornier Do X oli Dornierin valmistama aikanaan maailman suurin, painavin ja voimakkain lentovene. Koneen suunnitteluun meni suunnittelijalta, Claude Dornierilta, 7 vuotta ja ensimmäisen koneen rakentamiseen 2 vuotta.

Suunnitteluaikana koneesta rakennettiin 1:1-kokoinen puinen malli varsinaisesta metallisesta koneesta. Se oli ensimmäinen laatuaan.

Dornier Do X:llä oli duralumiinista tehty runko, siivet oli tehty teräsvahvisteisesta duralumiinikehikosta ja vahvasta kankaasta joka oli pinnoitettu alumiinimaalilla. Alun perin koneen voimanlähteenä oli kaksitoista 525 hevosvoiman Siemens Jupiter tähtimoottoria (6 veti, 6 työnsi). Koneen moottorit kuitenkin ylikuumentuivat testilennoilla, ja moottorit vaihdettiin kahteentoista 610 hevosvoiman vesijäähdytteisiin Curtiss Conqueror 12-sylinterisiin mäntämoottoreihin. 

Kuitenkin se pääsi matkalla ainoastaan 500 m:n korkeuteen, mikä oli tarpeellista Atlantin ylityksissä. Kone oli suunniteltu kuljettamaan pitkillä matkoilla 66 ja lyhyemmillä sata matkustajaa. Loistelias majoitus muistutti linjalaivojen loisteliaisuuksia. Pääkannella oli tupakointisalonki, ruokailuhuone ja penkit 66 matkustajalle. Penkeistä sai sängyt yölentoa varten. 

Matkustajatilojen takaosassa oli täysin sähköinen keittiö, WC:t ja matkatavaratilat. Ohjaamo, navigaatiotilat, koneiden tarkkailuhuone ja radiohuoneet olivat yläkannella. Alimmalla kannella oli polttoainetankit ja yhdeksän vesitiivistä osastoa

Dornier Do X:n valmistuttua se laskettiin vesille ensimmäiselle testilennolleen 12.heinäkuuta 1929. 21. lokakuuta kone kuljetti testinä 169 ihmistä, joista 150 oli matkustajia (pääasiallisesti konetta rakentaneita työläisiä ja heidän perheenjäseniään sekä harvoja lehtimiehiä) ja 10 miehistön jäsentä sekä 9 eräänlaista "salamatkustajaa". Lento rikkoi maailmanennätyksen kyydissä olleiden ihmisten määrällä. Ennätys pysyi Do X:llä 15 vuotta. Kone otti vauhtia 50 sekuntia ennen hidasta nousua ainoastaan 200 metrin korkeuteen. Koneen koosta johtuen, aina kun konetta kaarsi vasemmalle tai oikealle, matkustajia pyydettiin kasaantumaan joukkioksi aina vain toiselle puolelle jotta käännösten teko helpottuisi. Se lensi 40 minuuttia täyttä vauhtia (170 km/h) ennen laskeutumistaan Bodenjärveen.

Do X nousi ilmaan Friedrichshafenista Saksasta 3. marraskuuta 1930 ohjaajanaan Friedrich Christiansen, aloittaen transatlanttisen testilennon. Do X:n reitti kulki Alankomaihin, Isoon-Britanniaan, Ranskaan, Espanjaan ja Portugaliin. Matka katkesi Lissaboniin 29. marraskuuta 1930, kun siiven päällystekangas teki kontaktin kuuman pakokaasuputken kanssa aiheuttaen tulipalon joka tuhosi suuren osan toisesta siivestä. 

Kuuden viikon odotuksen Lissabonin satamassa jälkeen kun uudet osat vaihdettiin tuhoutuneiden tilalle, Do X jatkoi matkaansa pitkin länsi-Afrikan rannikkoa ylittäen Atlantin Etelä-Amerikkaan (missä miehistö vastaanotettiin sankareina paikallisissa saksalaisissa yhteisöissä). Do X jatkoi pohjoiseen Yhdysvaltoihin New Yorkiin 27. elokuuta 1931. Siellä kone ja miehistö olivat seuraavat yhdeksän kuukautta koska koneen moottorit tarkastettiin ja huollettiin.

Paluumatka alkoi 21. toukokuuta 1932 New Yorkista jatkuen Newfoundlandiin ja sieltä Azoreille ja lopulta Berliiniin 24. toukokuuta jolloin kone oli saanut suosionosoitusta noin 200 000 ihmiseltä.
-------------------------------
                    
General characteristics
Crew: 10-14
Capacity: 66-100 passengers
Length: 40 m[13] (131 ft 4 in)
Wingspan: 48 m[13] (157 ft 5 in)
Height: 10.25 m (33 ft 7 in)
Wing area: 450 m² (4,844 ft²)
Empty weight: 28,250 kg[13] (62,280 lb)
Max. takeoff weight: 56,000 kg (123,460 lb)
Powerplant: 12 × Curtiss Conqueror water-cooled V12, 455 kW (610 hp) eac
Maximum speed: 211 km/h (131 mph)
Cruise speed: 175 km/h (109 mph)
Range: 1,700 km (1,056 mi)
Service ceiling: 3200m (10498 ft)
Wing loading: 19.3 lb/sq ft (at 46 tons weight 

               
---------------------------------
The Dornier Do X was the largest, heaviest, and most powerful flying boat in the world when it was produced by the Dornier company of Germany in 1929. First conceived by Dr. Claude Dornier in 1924, planning started in late 1925 and after over 240,000 work hours it was completed in June 1929.

During the years between the two World Wars, only the Russian Tupolev ANT-20 Maksim Gorki landplane of a few years later was physically larger, but at 53 metric tons maximum takeoff weight it was not as heavy as the Do X's 56 tonnes.

The Do X was financed by the German Transport Ministry and in order to circumvent conditions of the Treaty of Versailles, which forbade any aircraft exceeding set speed and range limits to be built by Germany after World War I, a specially designed plant was built at Altenrhein, on the Swiss portion of Lake Constance.

While the type was popular with the public, a lack of commercial interest and a number of non-fatal accidents prevented more than three examples from being built.
The Do X was a semi-cantilever monoplane. The Do X had an all-duralumin hull, with wings composed of a steel-reinforced duralumin framework covered in heavy linen fabric, covered with aluminum paint.

It was initially powered by twelve 391 kW (524 hp) Siemens-built Bristol Jupiter radial engines (six tractor propellers and six pushers), mounted in six tower nacelles on the wing. The nacelles were joined by an auxiliary wing whose purpose was to stabilize the mountings. The air-cooled Jupiter engines were prone to overheating and proved to only be able to lift the Do X to an altitude of 425 m (1,400 ft). The engines were supervised by an engineer, who also controlled the throttle. 

The pilot would ask the engineer to adjust the power, in a manner similar to that used on maritime vessels. After completing 103 flights in 1930, the Do X was refitted with 455 kW (610 hp) Curtiss V-1570 "Conqueror" water-cooled 12-cylinder inline engines. Only then was it able to reach the altitude of 500 m (1,650 ft) necessary to cross the Atlantic.
Dr. Dornier designed the flying boat to carry 66 passengers on long-distance flights or 100 passengers on short flights.

The luxurious passenger accommodation approached the standards of transatlantic liners. On the main deck was a smoking room with its own wet bar, a dining salon, and seating for the 66 passengers which could also be converted to sleeping berths for night flights. Aft of the passenger spaces was an all-electric galley, lavatories, and cargo hold. The cockpit, navigational office, engine control and radio rooms were on the upper deck. The lower deck held fuel tanks and nine watertight compartments, only seven of which were needed to provide full flotation.

The Flugschiff ("flying ship"), as it was called, was launched for its first test flight on 12 July 1929, with a crew of 14. In order to satisfy skeptics, on its 70th test flight on 21 October there were 169 on board of which 150 were passengers (mostly production workers and their families, and a few journalists), ten were aircrew and nine were "stowaways" who did not hold tickets. The flight set a new world record for the number of persons carried on a single flight, a record that was not broken for 20 years. After a takeoff run of 50 seconds the Do X slowly climbed to an altitude of only 200 m (650 ft). As a result of its size, passengers were asked to crowd together on one side or the other to help make turns. It flew for 40 minutes (Flug Revue claims it was the 42nd flight and lasted 53 minutes, and historical film shows "fliegt mit 170 personen") at a maximum speed of 170 km/h (105 mph) before finally landing on Lake Constance.

To introduce the airliner to the potential United States market the Do X took off from Friedrichshafen, Germany on 3 November 1930, under the command of Friedrich Christiansen for a transatlantic test flight to New York. The route took the Do X to the Netherlands, England, France, Spain, and Portugal. The journey was interrupted at Lisbon on 29 November, when a tarpaulin made contact with a hot exhaust pipe and started a fire that consumed most of the portside wing. After sitting in Lisbon harbor for six weeks while new parts were fabricated and the damage repaired, the flying boat continued (with several further mishaps and delays) along the Western coast of Africa and by 5 June 1931 had reached the islands of Cape Verde, from which it crossed the ocean to Natal in Brazil, where the crew were greeted as heroes by the local German émigré communities.

Cover carried from Rio de Janeiro to New York on the DO-X, August 5–27, 1931

The flight continued north to the United States, finally reaching New York on 27 August 1931, almost nine months after departing Friedrichshafen. The Do X and crew spent the next nine months there as its engines were overhauled, and thousands of sightseers made the trip to Glenn Curtiss Airport (now LaGuardia Airport) to tour the leviathan of the air. The economic effects of the Great Depression dashed Dornier's marketing plans for the Do X, however, and it departed from New York on 21 May 1932 flying via Newfoundland and the Azores to Müggelsee, Berlin where it arrived on 24 May and was met by a cheering crowd of 200,000.