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PostPosted: Tue Nov 02, 2021 9:08 am 
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I started this project the 25 october 2021:

An order from a friend of the forum who is a 1/72 specialist and who would like to build a 1/72 Arado 196B (3 floats prototype) (Revell).

Only the 1/72 A3 bi-float model exists, or rather existed at Revell as it is no longer produced for the moment, but it is available on the private market.

My friend is going to use an A3 and put B floats on it, which Revell has already done for the 1/32 version with some minor modifications of the aircraft.

I accepted the challenge knowing very well this seaplane that I had built in 1/32 in B version and then A3 ( This last one is not produced any more either), plus a multitude of A3 in 1/200 for my Bismarck Trumpeter.

My Arado 196B in 1/32:
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Arado 196A3 in 1/32:
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So I downloaded the 1/32 PDF editing doc from Scalemate.com and found that there was enough information to draw them easily.

I captured the plans and made layers at the right scale on Fusion360, this allowed me to have the outlines of the floats and 2 couples on the central float:

I started the drawing this morning. It went pretty fast, each drawing of a "hull" (here it can be more like a mix of a submarine and a speedboat) allows to learn how to do better and better, and you always get a lot of little tricks each time.

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Some progress:

I'll try to fit some rivets.

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1400 rivets later!

I didn't follow the original float plan for the aluminium plates that make up the float. It would need 4 times as many rivets.

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The cables run up into the cockpit inside the brackets between the aircraft and the float.

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That's it for the central float, the two side balloons and their uprights still need to be drawn.

I'm waiting for a box of this Arado to perfect the fitting of the central float supports on the fuselage. It's precise. I need the size of the prints.

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_________________
Pascal

•Battleship Bretagne 3D: https://vu.fr/FvCY
•SS Delphine 3D: https://vu.fr/NeuO
•SS Nomadic 3D: https://vu.fr/tAyL
•USS Nokomis 3D: https://vu.fr/kntC
•USS Pamanset 3D: https://vu.fr/jXGQ


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PostPosted: Tue Nov 02, 2021 9:20 am 
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Plovdiv (Krumovo) Museum (PDV / LBPD) Bulgaria - August 1992:

One of the 3 remaining Arado 196's, of course there is no longer a copy of the 10 single float type B prototypes:

Arado Ar-196A-3, serial number 219.

Of the 541 examples built of this 1937 reconnaissance model, 12 were flown from Varna by the Bulgarian Navy during WWII. This one was almost destroyed in a post-war purge against Nazi artifacts, but was hidden.

It is now one of only three complete examples in the world, the other two being in the USA.

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The other two were recovered by chance from the Prinz Eugen before it was used as a nuclear test target:

At the end of the war, on 27 May 1945, the Prinz Eugen and the light cruiser Nürnberg - the only surviving large German ships - were escorted by the Royal Navy cruisers HMS Dido and HMS Devonshire to Wilhelmshaven harbour.

On 13 December, the Prinz Eugen was assigned as a prize to the United States, which sent the ship to Wesermünde. The USA was not particularly interested in having the ship, but rather in preventing it from being acquired by the Soviet Union. The cruiser was therefore integrated into the US Navy in a "miscellaneous ship" class as USS Prinz Eugen with the hull number IX-300.

She was present during two nuclear tests of Operation Crossroads - the Able 21 kT bomb test on 1 July 1946 and the Baker 23 kT underwater explosion on 25 July - at Bikini Atoll in the Marshall Islands in 1946, where she served as one of 90 target ships. Slightly damaged by the two nuclear explosions (she is located about 1 km from point 0), she is transferred to Kwajalein Atoll, where the damage was not repaired due to nuclear contamination. On 29 August 1946, the US Navy retired the Prinz Eugen.

At the end of December 1946, the ship was in a very bad condition. On 21 December, she began to list severely. A repair team did not have time to arrive, and the US Navy decided to beach the ship to prevent a sinking. But on 22 December, the Prinz Eugen capsized and sank with its tanks containing about 3,000 tonnes of fuel.



In addition to the wreck, which has become an attraction for scuba divers2, several parts of the ship have been preserved. One of her propellers can be seen today at the Laboe Naval Memorial near Kiel in Germany. Her bell can be seen in the National Museum of the United States Navy. Finally, two Arado Ar 196A-5s that were on the cruiser at the end of the war are in American collections. 623167 is part of the Paul Garber Collection and 623183 is part of the Willow Grove Collection.

In November 2018, operations to pump out the oil still present in the ship's tanks after 72 years, and now increasingly corroded, are being undertaken to prevent possible pollution of the atoll in the event of a typhoon.


THE ARADO 196

The Arado Ar 196 was the last combat seaplane built in Europe. It had become obsolete by the end of the Second World War, but during the war this aircraft served Germany well in all theatres of operation. It flew in the Atlantic and Indian Oceans as well as the Mediterranean, Baltic, Aegean, Black and North Seas.

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When the Third Reich came to power in 1933, the Kriegsmarine (German Navy) was equipped with the Heinkel He 60 biplane. This type had served in the Spanish Civil War and had excellent performance at sea, but was slow, poorly armed and very vulnerable at the start of World War II. An intermediate type, the Heinkel He 114, had poor water handling characteristics and slightly better flight performance than the He 60.

In the autumn of 1936, the Technical Office of the Reich Air Ministry (RLM) issued a specification that called for a two-seat aircraft powered by a single 800-900 horsepower engine with a single or two floats.

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Heinkel chose to continue trying to improve the He 114 but Arado, Dornier, Gotha and Focke-Wulf responded to the specification. Arado proposed an advanced monoplane design called the Ar 196 and the RLM ordered four prototypes (including two "B"). However, conservative elements in the Technical Board continued to favour biplanes over monoplanes and awarded Focke-Wulf a contract to build two more conservative aircraft, the Fw 62. The RLM subsequently cancelled the Fw 62 when the Ar 196 design demonstrated a clear superiority over its biplane competitor.

HE 114.
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FW 62
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Arado delivered the first two prototypes in the summer of 1937. Both were equipped with twin floats. Two more prototypes (B) soon followed, but these aircraft carried only one large central float and two small outrigger floats. Laboratory and water tests did not prove conclusively that one configuration was significantly better than the other. On landing, the single float held up better than the twin floats because it was directly attached to the fuselage, the strongest part of the aircraft. However, the twin floats had more stability when taxiing and manoeuvring. Weight and drag were also comparable, so the RLM asked Arado to prepare both types for production.

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RLM officials awarded a pre-production contract for 10 Ar 196A-0 double floats and Arado built the first one at its Warnemünde factory and delivered it to the Kreigsmarine in November 1938. The Shakedown tests left the naval authorities very happy and in June 1939, Arado began delivering the first production seaplanes (designated the Ar 196A-1) to the fleet.

At the outbreak of hostilities, the Kreigsmarine had selected many of its finest warships, including Admiral Graf Spee, Scharnhorst, Gneisenau, Deutschland, Admiral Scheer and Prinz Eugen to receive the Arado 196.

The Ar 196 aircraft flew well armed with a 20mm MG FF gun in each wing, a 7.9mm MG 17 machine gun in the nose of the fuselage and one or two 7.9mm guns in the rear cockpit. The aircraft could also carry a 50 kg (110 lb) bomb under each wing.

The Arado Ar 196 was first taken on board the 'Admiral Graf Spee' when the specialist trading aircraft embarked at Wilhelmshaven in August 1939. For four months the ship sailed the South Atlantic in search of merchant ships and launched its two Ar 196 catapults.

The Arados projected the battlecruiser's 'eyes' hundreds of miles away to search for potential targets. They found most of the 11 British casualties on the battlecruiser.

Many Ar 196s carried out coastal patrol missions from land bases. One notable action occurred on 5 May 1940, when two Ar 196A-2s from Aalborg, Denmark, captured a British submarine. HMS 'Seal' was laying mines in a narrow waterway called Kattegat when she hit one of her own mines. Attracted by the commotion, the Arados patrols attacked the submarine with guns and bombs and inflicted such damage that the boat could not be submerged.

One of the Arados landed next to the wounded submarine and its captain surrendered to the pilot. Other Ar-196 units operating along the French coast of the Bay of Biscay successfully intercepted RAF Whitley bombers attacking German submarines heading for their areas.

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The battleship Bismarck launched an Ar-196 in an unsuccessful attempt to chase an RAF Catalina that was observing her. Later, when Bismarck's situation seemed hopeless, an attempt was made to fly the ship's Ar-196s to France with letters from the ship's sailors and the ship's log. A malfunction of the catapult prevented this mission from being carried out.

Arado 196 in its hangar on the Bismarck.
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Ar-196 was not a fighter aircraft but 26 aircraft based near the Bay of Biscay flew patrols to intercept RAF Whitleys conducting anti-submarine patrols. 12 July, 3 August and 6 September 1942. Probably the last air victory of an Ar-196 in the Bay of Biscay occurred on 29 January 1943. An Ar-196, piloted by Oberleutnant Heinz Wurm and ground gunners shot down an A-20 Boston of 226 Squadron RAF. During this fight, the FW-190s shot down three Spitfires and lost one.

These operations typify the roles and capabilities of the Arado float plane. Not the most famous German aircraft of the war, the Ar 196 served ably, if unobtrusively, almost everywhere German forces went to sea. It was the main German maritime reconnaissance aircraft and its counterpart in the US Navy was the Vought OS2U Kingfisher.

Production was slow but steady throughout the war and the Kriegsmarine accepted only 94 aircraft in 1942. The Germans prepared a French factory at St. Nazaire to reinforce Warnemünde's efforts, but this company built only 10 aircraft before transferring production to the Fokker factory in Amsterdam. The Netherlands.

By the end of 1943, Fokker had become the main manufacturer. The Ar 196 became increasingly vulnerable to the faster and better armed Allied aircraft, which were going deeper and deeper into German-controlled territory. The RLM finally ended production in August 1944. Besides the German Luftwaffe and Kriegsmarine, Romania and Bulgaria also used the aircraft in limited numbers.

The final and definitive version was the Ar 196A-5. The NASM collection contains this type of aircraft.

Only three complete Ar 196s remain out of a total of 526 aircraft in production, excluding prototypes and pre-production aircraft. The Bulgarski Vozdushni Voiski Muzeum in Plovdiv, Bulgaria, displays an Ar 196A-3, one of the twelve Bulgarian Navy aircraft operating during WWII at Varna on the coast.

The Allies recovered two others from the German battlecruiser 'Prinz Eugen' when it went to Copenhagen, Denmark. The US Naval Aviation Museum in Pensacola, Florida, has one and the other belongs to the National Air and Space Museum.

The heavy cruiser Prinz Eugen was the largest German naval vessel to survive World War II. The Prinz Eugen is best known for sailing with the battleship Bismarck and as one of the ships that built the Channel Dash. The Ar-196A-5 did not enter service until 1943, so these aircraft were not involved in these battles. The main mission of the Ar-196 was to spot artillery. The Prinz Eugen bombed Tukum on 19 and 20 August 1944. The Prinz Eugen carried out artillery support operations from October 1944 to April 1945.

The Ar-196 at Paul E. Garber's installation, with its wings removed

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Arado Ar 196 A-5 at the NASM Silver Hill Paul E. Garber Preservation, Restoration and Storage Facility in July 1980
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Ar 196A-5, (Wk. Nr. 623167) coded + HG, T3 + BH, belongs to the National Air & Space Museum. The Allies recovered two Ar 196A-5s found on board the German battlecruiser Prinz Eugen when it surrendered at Copenhagen, Denmark.

Ar 196A-5 (Wk. Nr. 623183) coded T3 + CH is the second of these two aircraft and is being restored by the US Naval Aviation Museum in Pensacola, Florida.

The Norwegian Historical Museum in Sola, Norway, displays the fuselage frame of an Ar 196A-2 from the sunken German battleship Blücher.
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Arado Ar 196A-3 (Wk. Nr. 1003), parts stored in a Swedish Air Force museum.
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When the US Navy took custody of Prinz Eugen, they were more interested in the catapult system used to launch the seaplane than in the Ar 196A-5, but they saved both aircraft anyway. The Ar 196A-5 (Wk. Nr. 623167) in the MSNA has only 14 hours of operational flying time and the US Navy pilots added another four hours during testing and evaluation at the Naval Air Materiel Center in Philadelphia, Pennsylvania.

The US Navy obviously repainted the aircraft with markings copied from a different aircraft. This seaplane bore the code letters GA + DX (Wk. Nr. 68967). Today, the Ar 196A-5 in the National Air & Space Museum still bears the paint and markings of GA + DX. After years in storage, the Navy transferred the aircraft to the museum in 1961, where it is now preserved.

The two Arado Ar 196A-5 seaplanes were recovered from the German cruiser Prinz Eugen by US forces. The Arado Ar 196A-5 (Wk. Nr. 623167) is stored at the Paul E. Garber facility of the Smithsonian's National Air and Space Museum, awaiting restoration. Ar 196A-5 (Wk. Nr. 623183) has been in storage with the National Museum of Naval Aviation (NMNA) in Pensacola, Florida. This aircraft is currently on loan to the Aeronauticum Museum in Nordholz, Germany.

14 June 1946, US Operation Crossroads.

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TinTin and the mystery star:

The choice of a German model for the seaplane is not innocent: the Arado 196 . This choice, which is very controversial today, was justified because of the publication of the album in 1942 under the German occupation...

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My friend Sergio at work!

https://www.laroyale-modelisme.net/t143 ... evell-1-32

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_________________
Pascal

•Battleship Bretagne 3D: https://vu.fr/FvCY
•SS Delphine 3D: https://vu.fr/NeuO
•SS Nomadic 3D: https://vu.fr/tAyL
•USS Nokomis 3D: https://vu.fr/kntC
•USS Pamanset 3D: https://vu.fr/jXGQ


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PostPosted: Tue Nov 02, 2021 9:29 am 
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Printing of a prototype to check the correct configuration of print media.

I hollowed out the float with the Chitubox slicer.

Some modifications to be applied.

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Once you are free of the drawing and printing technique, your imagination can run free, no limits.

I hope to have my 1/72 box quickly now to finish.

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Difference between 1/32 and 1/72:

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I forgot one piece on the top of the float, a railing. I made some minor modifications.

Anyway the print is fine.

I will also print a rudder in the up position, so there will be a choice.

I found an Arado 196 A3 file on CgTrader in medium quality. I did a quick edit for fun.

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These "balloons" are almost finished. Rivets still to be fitted, the rear mooring rings and the locking cross arm.

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That's it!

This project is almost finished. I will be able to print the 2 balloons, the attachments are adapted to the dihedral of the aircraft.

I'm waiting for the 1/72 scale Revell model of the Arado 196 from Germany to adjust the main float attachments and print the final version. Then the printed parts are sent to England.

I will be able to return to my own 3D ship project in progress:

viewtopic.php?f=13&t=329319&p=963369#p963369

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Pascal

•Battleship Bretagne 3D: https://vu.fr/FvCY
•SS Delphine 3D: https://vu.fr/NeuO
•SS Nomadic 3D: https://vu.fr/tAyL
•USS Nokomis 3D: https://vu.fr/kntC
•USS Pamanset 3D: https://vu.fr/jXGQ


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PostPosted: Tue Nov 02, 2021 12:47 pm 
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Certainly a different project for these pages! The design of the tail of the central float is interesting with it's ducktail. I was at one time a professional float plane pilot and still own one. The Ducktail would be for rough water operations as the increase in immersion depth would generate much less buoyancy than the more typical extension of the broad V bottom as seen on most float planes for stability and for use with a greater degree of Center of Gravity during takeoff and landings. Such ducktails are often found on the hulls of flying boats, which are notoriously susceptible to dynamic longitudinal instability with high speed water operation. The catapult operation would be fairly awkward with a twin float arrangement.

Yes, an effort to fly the Bismarcks "Kriegstagsbuch" to shore was made but the third hit by POW which had done little obvious damage had with splinters cut the compressed air line that powered the catapult. Perhaps the pilot might have opted for an attempt to be lowered over the side and attempt a water takeoff despite the steep seas. Sitting on board and waiting to get sunk was the only other option.

Just curious what the item protruding below the aft portion of the float on the centerline is. This would cause an extreme amount of hydrodynamic drag!

Cheers: Tom


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PostPosted: Tue Nov 02, 2021 1:40 pm 
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May be thingy under the float is meant to create a Lürssen-effect: [url]https://en.wikipedia.org/wiki/Lürssen_effect[/url] ?

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PostPosted: Tue Nov 02, 2021 4:07 pm 
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Thanks for the informations Tom.


You can see these system called "Redan" also on speed boat ( Competition ).

Main features of seaplanes

The profile of the hull or floats of any seaplane is broken by a floats is broken by a transverse step, the effect of which
effect is to reduce hydrodynamic drag and hydrodynamic drag and to facilitate tilting backwards during lift-off.

The speed then increases speed increases rapidly to between 20 and 30 knots, to a hydroplaning situation allowing to control
to control curved trajectories.

http://www.planete-tp.com/IMG/pdf/Princ ... 6367c5.pdf

The redan hull: a major invention!

In 1872, the English pastor Ramus made a major invention. He built a flat-bottomed canoe with a stepped hull. By testing a full-size canoe on the Thames, he demonstrated that the step increases the speed of the boat on the water. Ramus then proposed his invention to the British Admiralty. Dinghy boats were built and tested in Calshot, England. In each case, the speed of the boat was increased by at least ten knots compared to the same hull without a step. The hull of the speedboats was born: all hovercraft since then have been equipped with a stepped hull.

English pastor Ramus Hull:
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Between boat and plane: the first seaplane

In the family business of building sailboats and fast boats, Alphonse Tellier lived through the pioneering period of aviation. His father's shipyards supplied Victor Tatin with 'heavier than air' (aeroplanes, gliders) and Charles Krebs with 'lighter than air' (aerostats). Alphonse Tellier equipped his hulls with engines and took part in the competitions of the time.

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The first hull seaplane, the Donnet-Levêque A (1911)



Alphonse Tellier, like Denhaut, can be considered as the inventor of the hull seaplane, even if he never claimed it: in the summer of 1912, Louis Bréguet asked him to build a finned hull for a heavy seaplane, La Marseillaise, seaplane,

La Marseillaise. Built on the Ile de la Jatte, France, this large canard monoplane, a monster weighing more than 1,400 kg, capable of floating but not flying, was the first prototype of a heavy military seaplane, such as would exist four years later. The
Marseillaise was exhibited at the end of 1912 at the Grand Palais in Paris, at the 4th aeronautical show, next to the Donnet-Lévêque, the first hull seaplane to fly properly.
source

It was this technology that inspired Y. Parlier to equip his Catamaran with a stepped hull that allows seaplanes to take off and land at high speed. They allow to obtain a dynamic support on the water and to facilitate the lift of the hulls from a certain speed. Finally, when the aircraft reaches a much higher speed in the planning phase, it takes off without any "suction cup" effect on the hulls. They also avoid braking during the take-off and landing phases. The speed of these hulls is not limited. Seaplanes can take off at more than 250 km/h, and motor catamarans with stepped hulls can reach a top speed of 260 km/h.

All multihulls today operate on Archimedes' principle regardless of their speed. The resistance to forward motion of Archimedean hulls increases with the square of the speed, blocking access to average speeds of 40 to 50 knots.

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The two positions of the stepped hull at increasing speed

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Hydroplaneur by Y. Parlier's Hydroplaneur with its two masts offers 4 times less resistance and 10 times less submerged surface than a Catamaran of the same size.

Thus, the progress brought to the construction of canoes by the redan was transferred to the hydroplane. Then, the properties of the seaplane were transferred back to the two hulls of the catamaran.

http://www.jf-doucet.com/approche/Produ ... ARedan.htm

Dornier DO24
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https://www.researchgate.net/figure/Hul ... _320934669

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•Battleship Bretagne 3D: https://vu.fr/FvCY
•SS Delphine 3D: https://vu.fr/NeuO
•SS Nomadic 3D: https://vu.fr/tAyL
•USS Nokomis 3D: https://vu.fr/kntC
•USS Pamanset 3D: https://vu.fr/jXGQ


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PostPosted: Tue Nov 02, 2021 4:44 pm 
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Some personal photos taken in June 2021 in the seaplane museum in Biscarrosse, France, one of the most famous old seaplane bases in Europe.

Located on the mythical site of the former Latécoère base in Biscarrosse, the Seaplane Museum traces the history of seaplanes.

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A replica of the famous first Donnet-Lévèque hull seaplane.

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•Battleship Bretagne 3D: https://vu.fr/FvCY
•SS Delphine 3D: https://vu.fr/NeuO
•SS Nomadic 3D: https://vu.fr/tAyL
•USS Nokomis 3D: https://vu.fr/kntC
•USS Pamanset 3D: https://vu.fr/jXGQ


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PostPosted: Tue Nov 02, 2021 5:53 pm 
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Very interesting, the rapid development of these technologies. Large seaplanes had some advantages in that era as large airports for land planes were not so ideally spaced or available, and very long takeoff spaces could be utilized. In addition, over oceans it was not necessary to have a capability to climb to high altitude.

At least for smooth water, takeoff is the limiting factor and weight and altitude are the biggest factors to consider. Weight limits the ability for the aircraft to get on the step, plaining position. Without this acceleration to takeoff speed is not possible. Altitude increases the true airspeed necessary to generate sufficient lift. Hydrodynamic drag increases at least with the square of the increase in speed and a minor increase in altitude can increase the drag such that a takeoff run may exceed the available area, or flying speed cannot be achieved. I have seen float planes fail to become airborne at even 2000' MSL. Operating my Super Cub out of mountain lakes, which I will describe as twice as high as long, could be challenging!

During WWII as an experiment, the C-47 was equipped with a large pair of custom made EDO floats. Though it performed satisfactorily, it was no more useful than the PBY, of similar size and performance. There were several WWII fighters equipped with floats including the Japanese Zero sen, the F4F Wildcat and the MkV Spitfire. Probably the Zero was the most utilized of these, seeing considerable service in the Solomon Islands.

Tom


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PostPosted: Wed Nov 03, 2021 2:46 am 
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The stepped floor design was indeed used for speed-boats for several decades, until the 1960s or so, I think. It kind of adds a virtual extension to hull, allowing speeds exceeding the hull speed and when gliding begins, it reduces the wetted surface and hence drag.

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PostPosted: Wed Nov 03, 2021 2:59 pm 
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The subject of hull speed is raised, and of course standard aircraft floats use the "transom stern" effect which when plaining make dynamic and surface friction effects dominate. the idea of the V hull is to reduce the surface friction as the dynamic resistance increases with speed by lifting the hull further out of the water. These would tend to be a deeper V due to a predominance of rough water operations.

USN Cruisers and destroyers tended to use transom sterns, including the large cruiser Alaska which optimized lessened resistance at higher speeds but were not as effective at lower speeds. They made up for this due to the advanced high temp and pressure power plants they had available. RN Vanguard also utilized a transom stern as do the modern generation of super carriers. The advantage at speed here is extending the effective hull length as far as wave making resistance is concerned. When air becomes less compressible nearing the speed of sound the drag curve rises sharply, which is somewhat analogous to increasing wave making resistance with increasing speed.

As a note, the floats were never left bare aluminum but when looking so are actually painted with an aluminized float lacquer. The bow is often black as the bulb is actually a rubber bumper. I wasn't able to identify them, but always there will be pump out fitting on the top as any water (which does seep in) must be removed as it can badly affect CG and weight.

The design of the tip floats is rather unusual. Not having personal experience with these I can't comment.

Not a ship model per se, but shipboard equipment.


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PostPosted: Wed Nov 03, 2021 5:53 pm 
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The redan create bubbles and cavitation, a bit like a torpedo with super cavitation, the friction is reduced with a mattress of bubbles.

https://www.popsci.com/scitech/article/ ... g-torpedo/

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•SS Delphine 3D: https://vu.fr/NeuO
•SS Nomadic 3D: https://vu.fr/tAyL
•USS Nokomis 3D: https://vu.fr/kntC
•USS Pamanset 3D: https://vu.fr/jXGQ


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PostPosted: Wed Nov 03, 2021 7:24 pm 
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With these and the equivalent hypersonic airborne vehicles are at interesting edges of technology. I only saw one hypersonic vehicle, once, putting along on a dark night over Saudi Arabia before the second Gulf War. An unmanned aircraft maybe 80, 000' or higher heading south out of Iraq going to my estimation Mach 6 or so, one could dee it from the pulsed exhaust, there and gone!

As the author alluded steering is a big challenge. A friend was a EWO on B'52's based out of Okinawa and had quite few SAM's fired in his direction. High speed cuts down transit time, but also severely reduces maneuverability which gives many advantages to countermeasures as followup corrective response will probably not be possible.

Certainly enough to keep the countermeasures Boffin's dreaming at night!


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PostPosted: Sat Nov 06, 2021 7:47 am 
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Drawing of the last parts, the rigid struts of the central float. 

The latter has been modified at the level of the attachments to fit perfectly the float prints of the Revell model fuselage.

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PostPosted: Sat Nov 06, 2021 1:33 pm 
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Certainly different aluminum construction methods could be used but the float with the cutaway seems to use traditional methods used to this day. Though the lighting doesn't make this obvious in the above photo, there is usually little flange exposed on the outboard side of the V bottom where it meets the sidewalls. The reason for this is to allow riveting externally along the edge as interior riveting is considerable more difficult and this makes fro fewer rivet holes penetrating the hull. The sidewalls would be riveted to the T section first then the bottoms, which allows for easier replacement of the bottom skins, where damage is most likely. In addition the flange allows a very clean separation of the flow when plaining.


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PostPosted: Sat Nov 06, 2021 5:35 pm 
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Thanks Tom for the clarification! :thumbs_up_1:

That's it, it's over.

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PostPosted: Sat Nov 06, 2021 6:11 pm 
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Very nice 3D work on continuous compound surfaces! Being able to work with such surfaces is personally a future aspiration.

Interesting information about the Arado float plane, I was surprised that steel frame and fabric construction was used, similar the the fuselage of the Hawker Hurricane. The scout aircraft are not such a well known area and many configurations existed. The Curtis SOC biplane was especially versatile in being an amphibian and being able to takeoff and land on the deck of an aircraft carrier, being equipped with an arresting hook. I would have been fascinating to sit in on the discussion at Arado on one float vrs two.

Informative as usual! Tom


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