Late 1930s and/or WWII fighter flying boats?

I know of a number of WWI and 1920s designs for fighter flying boats--various Macchi and Caproni designs and the Supermarine Baby and related racers, for example. I also know of a number of post-WWII designs for jet flying boat fighters like the Saro and even the Convair Sea Dart.

Does anyone know of any prototypes or projects for fighter flying boats from the late 1930s and/or WWII periods? I'd also be interested in single-seat or perhaps two-seat attack flying boat designs that could have taken on a fighter role. It would be great to see what R.J. Mitchell could have done with a specification for a flying boat fighter, for example.

The only one that comes to mind for me is the Blackburn B44, a Blackburn Firebrand with the retractable hull of the Blackburn B20 experimental test aircraft. It's in the WWII-era volume of BRITISH SECRET PROJECTS. There is an artist's impression and a little info online on John "Dinger" Dell's site (scroll down).

I am specifically asking about flying boats, not float seaplanes. There are a lot of single- and twin-float seaplanes that would fit the bill, I am talking about aircraft with boat hulls, whether amphibious or water-only flying boats.

Please see http://www.secretprojects.co.uk/forum/index.php/topic,2276.0/highlight,blackburn%20b%2044.html
http://www.secretprojects.co.uk/forum/index.php/topic,2313.0/highlight,blackburn%20b%2044.html

Hehe, was editing my initial post to include the B44 when you posted.

A couple of projects of 30-ies of the Soviet Union.
IM "Marine Fighter" by Shavrov and
Fighter "Alpha"MPI (morskoy podvesnoy istrebitel = marine suspended fighter) engineer Vasil'yev (1937)
Sources: Aviation and Cosmonautic "1998 № 11-12
G. Petrov "Seaplanes and ekranoplans of Russia 1910-1999"

That Shavrov design is great, anyone have any projected performance, armament specs?

I agree, once again - thank you Borovik!

The Shavrov IM figher appears to be an extrapolation of the mass-produced Shavrov Sh-2 amphibian. See the Wikipedia and Virtual Aircraft Museum entries for photos, 3-views, specs. My Russian is almost nil, but the caption to the 3-view that Borovik posted seems to indicate a 400 hp engine. Considering that the three-seat Sh-2 had a maximum speed of only 86 mph with its 100 hp engine, it seems unlikely that even a smaller and aerodynamically neater version would have done much over 200 mph with 400 hp (the Italian Cant 25 biplane fighter/observation flying boat of the same period could only do 150 mph with similar weight and horspower). Still, with a couple of machine guns and light bombs the Shavrov IM could have made a useful close support aircraft operating from forward bases near the front lines and hunting enemy observation aircraft like the Fieseler Storch.

"..would have done much over 200 mph with 400 hp "

Quite correct, I think. It's similar to the Potez 453, which is
said to have reached 198 mph(318 km/h) with a 720hp engine

http://www.aviastar.org/air/france/potez-453.php

The IM drawing isn't too accurate.
Jupiter has 9 cylinders, but there are only 5 on drawing.
It seems this drawing really was "modified" from Sh-2 one.

borovik said:

A couple of projects of 30-ies of the Soviet Union.
IM "Marine Fighter" by Shavrov and
Fighter "Alpha"MPI (morskoy podvesnoy istrebitel = marine suspended fighter) engineer Vasil'yev (1937)
Sources: Aviation and Cosmonautic "1998 № 11-12
G. Petrov "Seaplanes and ekranoplans of Russia 1910-1999"

Click to expand...

My dear Borovik,


the art work for Shavrov IM fighter flying boat;


http://alternathistory.org.ua/letayushchaya-lodka-istrebitel-im-shavrov-projekt-1930g

Hi,


here is Art work for KB-2 MPI fighter floatplane project,and a drawing
to the retractable float,to see how it work.


http://alternathistory.org.ua/morskoi-istrebitel-mpi-alfa-vasilev-proekt-1936g

The Loire 210

http://www.aviafrance.com/aviafrance1.php?ID=3934&ID_CONSTRUCTEUR=836&ANNEE=0&ID_MISSION=0&MOTCLEF=

Wow, 315 kph/196 mph maximum speed is pretty pitiful for that Loire 210 as a fighter in 1937, even a floatplane. For comparison, a Mitsubishi F1M "Pete" was faster than that as a biplane and a two-seater.

dogsbody said:

The Loire 210

http://www.aviafrance.com/aviafrance1.php?ID=3934&ID_CONSTRUCTEUR=836&ANNEE=0&ID_MISSION=0&MOTCLEF=

Click to expand...

Yes Dogsbody,we forget it.

Maybe a silly question about the KB-2 MPI/Vasil'yev "Alpha"MPI:
What was this elaborate construction of the rotating cover for ? As far as I can see
from the drawings, it was above the waterline at all times, so the increase of internal
volume couldn't be the reason.

Design by R J Mitchell from 1921

Great find Schneider,


but was the designer French or from anther country ?.

hesham said:

Great find Schneider,


but was the designer French or from anther country ?.

Click to expand...

It looks like RJ Mitchell could have designed it - I'm curious as to what makes you think he didn't.

Jemiba said:

Maybe a silly question about the KB-2 MPI/Vasil'yev "Alpha"MPI:
What was this elaborate construction of the rotating cover for ? As far as I can see from the drawings, it was above the waterline at all times, so the increase of internal volume couldn't be the reason.

Click to expand...

Assuming the rotating cover has a water tight seal against the float - if it doesn't, you'll have a very leaky float - this construction provides reserve buoyancy. It also allows the fuselage to protrude into the retracted float, which offers opportunities to reduce the frontal area of the aircraft with float retracted, while offering more space inside the fuselage for equipment or fuel. A float that's simply hollow on top is likely to be swamped when the aircraft is water borne at any speed.

Oh my God,


he was a Supermarine designer;


http://en.wikipedia.org/wiki/R._J._Mitchell

Arjen said:

...- this construction provides reserve buoyancy.

Click to expand...

Thanks Arjen ! I should have used from the beginning the 3-view to check, not the colour profile !
Because there, the auxiliary float is shown too long, I think, and if that additional volume becomes effective,
the auxiliary floats would already be undercutting and quite probably torn off !

In June 1936 Blackburn proposed their BB5 project for a twin-engined 2/3 seat amphibian reconnaissance/fighter. 2xBristol Aquila, Gross weight 8500lb, 50ft span, length 39ft 6in, max speed 260mph. The armament was four machine guns in a remote controlled dorsal turret. Think of it as a scaled-down B-20 as it aircraft would have had a retractable hull and retractable wing tip floats, but plus a retractable undercarriage and folding wings for stowage onboard carriers.

Schneiderman said:

In June 1936 Blackburn proposed their BB5 project for a twin-engined 2/3 seat amphibian reconnaissance/fighter. 2xBristol Aquila, Gross weight 8500lb, 50ft span, length 39ft 6in, max speed 260mph. The armament was four machine guns in a remote controlled dorsal turret. Think of it as a scaled-down B-20 as it aircraft would have had a retractable hull and retractable wing tip floats, but plus a retractable undercarriage and folding wings for stowage onboard carriers.

Click to expand...

Thank you my dear Schneiderman,

any drawing ?.

Yes.....but. The documents come from the BAe Systems Heritage archive and I do not have clearance to share at the moment.

Schneiderman said:

Yes.....but. The documents come from the BAe Systems Heritage archive and I do not have clearance to share at the moment.

Click to expand...

OK and thanks.

Clarification of an old post...thanks to a Russian OCR extraction and Google Translate, I can confirm that the Shavrov IM project drawing posted by borovik reads:

проект
(1930 г.)

"Истребитель морской” под 400-сильный мотор "Юпитер”

project
(1930)

“Marine Fighter” under 400-strong Jupiter motor

That suggests a 400 hp Shvetsov M-22, a license-built Bristol Jupiter 9-cylinder single-row radial, though the drawing still shows the 5-cylinder M-11 of the Shavrov Sh-2.

I know they are not strictly fighters, but what about the whole: Loening, Grumman and Columbia series of amphibians?
These amphibious biplanes were mainly used for scouting, target-towing, utility, search and rescue, but could carry small bombs or depth charges and many were armed with a machine gun or three. Some Grumman Ducks flew short-range anti-submarine patrols early in WW2.
They sort of looked like floatplanes with large center floats and small balancing floats under wingtips. The key difference was that fuselages faired into center floats to create large passenger cabins. They had full-length fuselages and full-length center floats. Most crews included a pilot, observer/rear gunner and maybe a second observer. The last Grumman Duck to escape from the Phillipines carried a total of 7 people! See the book "I Saw the Fall of the Phillipines.mman-designed)

Grover Loening started the line with his OA-1A amphibian of 1927. He sold a 165 OA-1As - mainly to the US Navy - between the wars.
Leroy Grumman took over with his up-dated J2F1-6 Duck (1936). Duck was by far the most popular of this genre (total of 584 built).
Columbia took over Duck production (330) during WW2 when Grumman got too busy building fighters and torpedo bombers.
In 1946, Columbia built a pair of XJL monoplanes that looked like up-dated Ducks.
The oddest looking of that ilk was the 1931 Great Lakes XSG prototype that looked like a Duck missing a chunk of fuselage between the observer and rudder.

As an aside, I vaguely remember a photo of an Edo prototype of a monoplane, single-seater flying boat with a high-mounted, tractor engine.

The Loening OL series and the Grummand Ducks were certainly armed but I don't think any of them were used (or ever intended to be used) as fighters. Still, I have always loved the look of the Loenings, maybe an LSA version with lots of space for camping gear. ;-)

From the Blackburn B.44 thread:

(h/t Justo Miranda for the side profile below)

Shavrov IM. Box art by Eugeny Knupfer (with the correct image of the engine)

Very cool, borovik, though it's odd that they chose to show the streamlined struts in the drawing as wires in the art.

borovik said:

Shavrov IM. Box art by Eugeny Knupfer (with the correct image of the engine)

Click to expand...

Potez 453

One photo of a Sikorsky flying boat prototype from the 1930s.

hesham said:

nHi,


here is Art work for KB-2 MPI fighter floatplane project,and a drawing
to the retractable float,to see how it work.


http://alternathistory.org.ua/morskoi-istrebitel-mpi-alfa-vasilev-proekt-1936g

Click to expand...

That rotating part does not even need to be made of aluminum. A rubber balloon would be enough (ala. Lotus inflatable floats currently sold for ultra-lights), which only have a rigid plastic forward (of the step) planning float bottoms. The remainder of Lotus floats are made of aluminium tubes and inflatable cylinders.

Schneiderman said:

In June 1936 Blackburn proposed their BB5 project for a twin-engined 2/3 seat amphibian reconnaissance/fighter. 2xBristol Aquila, Gross weight 8500lb, 50ft span, length 39ft 6in, max speed 260mph. The armament was four machine guns in a remote controlled dorsal turret. Think of it as a scaled-down B-20 as it aircraft would have had a retractable hull and retractable wing tip floats, but plus a retractable undercarriage and folding wings for stowage onboard carriers.

Click to expand...

The remote control dorsal turret, any information on it?

How did it compare to say the remote control turrets on the Douglas A-26?

Here's a drawing of the Macchi M.41bis in Spain and some photos from my files. The M.41bis may have been the last fighter flying boat to see combat.

PMN1 said:

The remote control dorsal turret, any information on it?

How did it compare to say the remote control turrets on the Douglas A-26?

Click to expand...

No mention of the turret at all in the specification document, this is how it appears in the drawing

When Allies decided to counterattack in the Pacific, with insufficient number of aircraft carriers, they had to face the fact that airborne operations depended on the availability of landing strips and that most of them –along with the islands where others might be built- where in Japanese hands. It proved to be very costly in lives and resources to occupy them.

Circumstances demanded the use of any type of floatplanes and flying boats that the Allied had in great numbers. Main problem was the absence of shore-based floatplane fighters able to protect them and to provide the necessary air support for their amphibious forces.

The main disadvantage came from the way in which the bulk of their floats penalised their performance compared with the conventional Japanese fighters.

Americans performed some testing with a float equipped F4F-3S Wildcat at the beginning of 1943 but they renounced to use it in combat due to its low performances.

The British updated the old idea of a floatplane Spitfire, developed during the Norwegian campaign, and they modified a Mk. IX (MJ892) that during testing proved to have superior maximum speed and manoeuvrability compared to the enemy floatplane fighters Mitsubishi A6M2-N and Kawanishi N1K1, but the whole scheme was abandoned early in 1944.

By 1943 turbojets were available and other manufacturers proposed jet fighters with a low-drag flying boat hull not requiring water clearance for a propeller.

Jet power would be able to provide the Allies with a water-based fighter of superior performance against the Japanese piston-engined types.



The Airspeed firm suggested to the Admiralty the transformation of the radio-controlled flying-boat target aircraft AS-37 into a scaled-up jet fighter, powered by one de Havilland Halford H.1 centrifugal-flow turbojet with 1,225 kgf static thrust in the forward area of the hull with the air intake positioned in the extreme nose.

Technical data

Wingspan: 32.5 ft (9.93 m), length: 30 ft (9.14 m), height: 5.9 ft (1.8 m), wing area: 187 sq. ft (17 sq. m), proposed armament: four 4.5 in (11.5 cm) recoilless cannons

On December 1943 the Saunders-Roe firm presented their SR.44 project to the Ministry of Aircraft Production. The original design, with low-set gull-wing configuration and Halford turbojet, was modified to meet the E.6/44 specification and three prototypes, powered by two Metrovick Beryl F2/4 axial-flow turbojets, were ordered in April 1944 under the denomination SR/A-1.

By 1945 the Americans were able to build enough aircraft carriers to support air operations in the Pacific, official interest in the SR/A-1 waned and their development stayed at low priority.

With the end of the war Saunders-Roe concentrating its resources in the development of the SR.45 Princess long range civilian flying boat.

The SR/A-1prototype (TG263) flew on July 16, 1947 but the project was suspended on August 1949 after the cancellation of the Beryl turbojet.

Technical data

Wingspan: 46 ft (14 m), length: 50 ft (15.2 m), height: 16 ft 9 in (5.1 m), wing area: 415 sq. ft (37.3 sq. m), max speed: 512 mph (824 kph), max weight: 19,033 lb (8,622 kg), ceiling: 43,000 ft (13,100 m), proposed armament: four 20 mm Hispano Mk V cannons with 760 rounds each, power plant: two Metropolitan-Vickers Beryl F.2/4 axial-flow turbojets with 1,463 kgf static thrust.

In 1942, Blackburn proposed the B-43, a single seat twin-float fighter with a Napier Sabre engine based on the Firebrand.

In 1943 they came with the idea of the B-44, a much more complex design with retractable hydraulically-operated floats.

The idea was not new. German already built the Ursinus Seaplane during World War One The plane was fitted with a retractable twin-float undercarriage and reached a maximum speed equivalent to that of the British Sopwith Snipe.

Bill Barnes adventure stories made popular again the formula of the 30s with two extraordinary fiction models, the Scarlet Stormer in 1934 and the Lancer in 1936.

In 1938 the French aircraft manufacturer Latécoère published three projects (no. 671, 672 and 673) of seaplane fighters fitted with retractable floats.

In March 1940 the Blackburn firm built and fly tested the B-20, a medium-sized general reconnaissance flying boat equipped with hydraulically operated retractable hull bottom.

Testing was satisfactory but the only prototype was destroyed in a crash in April and the RAF preferred to recommend the manufacturing of the Saro Lerwick instead.

The B-44 have benefited from the experience obtained with the B-20, but the unfortunate Firebrand story, the increasing number of available aircraft carriers in the Pacific and the success in building ground airfields after amphibious landing were against its manufacturing and the idea never came to materialise. The project was cancelled in 1944.

B-44 technical data

Power plant: One Napier Sabre Mk IV, 24 cylinder ‘H’, liquid cooled engine, rated at 2,300 hp, driving two contra-rotating airscrews, wingspan: 50 ft (15.2 m), length (flight configuration): 39.7 ft (12.1 m), height (water configuration): 13.3 ft (4.06 m), wing surface: 393 sq. ft (35.4 sq. m), maximum speed: 360 mph (579 kph), service ceiling: 38,000 ft (11,582 m), range: 1,000 mls (1,609 km), armament: four wing-mounted 20 mm Hispano Mk.V cannons.

but what would be look of the ship that was supposed to carry these planes