IJN Specification 12-Shi (E12/E13, Reconnaissance Seaplane, 1937)

Hi! Kawanishi E13K.

http://www.airwar.ru/enc/sww2/e13k.html

Auto translation.

In 1937, the Imperial Japanese Navy decided to change the old Scout Kawanishi E7K seaplanes (Navy Type 94 Reconnaissance Seaplane) to more advanced aircraft. For this purpose, contracts were signed with companies from Aichi and Kawanishi at the design and construction of long distance reconnaissance seaplanes, which can be used with catapult ships and shore bases.


The company already started Kawanishi in March of the same year. The first of two prototypes flew on September 28, 1938. It was all-metal, low-wing monoplane with twin četyrnadcaticilindrovym air cooled engine Mitsubishi Kinsei 3-Kai with 910 HP aircraft consisted of one defensive machine gun Type 92 7.7 in the rear cockpit and a 250-kg bomb under the fuselage or four bombs up to 60 kg in the hardpoints under the wings.


In October, under the designation E13K1 (12-Shi Three-seat Reconnaissance Seaplane) flight passed over for fleet base at Aichi E13A1. The E13K1 has surpassed rival in most characteristics (except top speed), but proved to be more difficult to operate and maintain. The winner was a seaplane of Aichi.


Soon after the first prototype was destroyed in the crash, and a second disappeared during the test flight.

Winner Aichi E13A.
http://www.youtube.com/watch?v=qT-3xsDXvt0

Hi

Aichi E 12 A-1 here

The IJN announced unofficially development of the 12-shi 3 seat reconnaissance plane which serves as an inheritor of a 94 type reconnaissance sea plane on the Kawanishi and the Aichi in 1937.
The contents of a demand over a 12-shi 3 seat reconnaissance plane were the long-distance reconnaissance planes which can be employed not only from employment as a ship airplane but from an aquatic base.
The demand time for delivery of the experimental model was in September, 1938.
The Kawanishi completed the trial production of No. 1 of the 12-shi 3 seat reconnaissance plane(E13K) just before demand time for delivery, and made the first flight successful in September.
The structure of the body was total metal stressed-skin structure, and the engine was Mitsubishi Kinsei.
The wing outside portion can fold up to the inner side upper part.
The armament were backseat equipped 7.7 mm revolution type machine gun, and four 60-kg or one 250-kg bomb equipped under the body or a wing.
Performance examination of the 12-shi 3 seat reconnaissance plane by the IJN started in October, 1938.
On the other hand, manufacture of the experimental model did not meet the deadline at the time for delivery which the IJN ,the Aichi was disqualified.
However, the Aichi advanced manufacture of an experimental model uniquely, completed the trial production of No. 1(E13A) in January, 1939, and completed the trial production of No. 2 in June.
When process of performance examination of No. 1 of the Kawanishi, it became clear that there was a problem in practicality and strength of structure.
A flutter generated the trial production of No. 1 during test flight, and the trial production of No. 2 has gone missing during a flight.
The IJN decided to also examine the experimental model of Aichi.
Although the experimental model of the Kawanishi excelled the experimental model of the Aichi in flight performance except for the maximal speed, it was judged as practicality and reliability being inferior.
Finally the IJN carried out formal adoption of the 12-shi reconnaissance sea plane of Aichi(E13A) as a zero type reconnaissance sea plane in 1940.

Hi

Thanks for those information !
On the internal arrangement drawing of the Type 0 Mk11b a "magnetic
detector" is shown. Was it for ASW work ? Didn't hear of such a device
in Japanese use still yet.

:-\

¿...?

I seem to remember Rene Francillon mentioning both ASW radar and magnetic detectors in his wonderful Japanese Aircraft of the Pacific War either in the context of Aichi and Kawanishi float planes or maybe the land-based Kyushu Q1W. Wikipedia lists the Q1W as carrying Type 3 Model 1 MAD (KMX), Type 3 Ku-6 Model 4 Radar and ESM Antenna equipment with Francillon as the source.

http://en.wikipedia.org/wiki/Kyushu_Q1W

Wow MAD! Thanks a lot.

Please see and enjoy:


http://www.fischer-tropsch.org/primary_documents/gvt_reports/USNAVY/USNTMJ%20Reports/USNTMJ-200B-0504-0540%20Report%20E-14.pdf

The IJN opted for development of all the metal cantilever mono wing reconnaissance sea planes which were the trends in the world as an inheritor of the biplane reconnaissance sea plane (except for a flying boat type aircraft) which was being used till then, and pointed to experimental model development to Kawanishi, Aichi and Nakajima in Showa 12 (1937).
Although Kawanishi which was tackling large-sized flying boat development did not participate in this competition trial production, Nakajima (E12N) and Aichi (E12A) were made as an experiment. The aircraft were completed in Showa 13 (1938).
Nakajima and Aichi both companies submited all the metal cantilever low mono wings twin float aircraft and received examination of the IJN.
Nakajima E12N had a straight line tapered wing, and Aichi E12A had a parabola tapered wing.
However, since those aircraft were mono wing sea plane which were inexperienced in manufacture until the day, there were problems for operation and stability. The IJN did not select both aircraft.

I can't find any Nakajima E12N picture or drawing in Japanese sources still now .

Hi! Nakajima E12N.
http://www.airwar.ru/enc/sww2/e12n.html

The first, in June 1937, the Navy proposed that companies Nakajima and Aichi, in accordance with the issued specification 12-Shi to design and build a runnable twin catapult seaplane Scout. In addition to the functions of the razvedchika prektiruemyj specification 12-Shi seaplane was to be able to perform diving operations with anti-ship 250-kg bomb at an angle of 60°.


Design work on a new plane in the company of Nakajima began in the summer of 1937, under the leadership of Sinroku Inoue (Inoue Shinroku). To enable additional features dive-bombing Aichi and Nakajima took dvuhpoplavkovuû configuration oblegčavšuû suspension of the bomb. Nakajima was the feature of the development of a mechanism to move the bomb that moves it in front of the sbrosmo out of the ometaniâ screws. To decrease drag in the bottom of the fuselage recess was taken to contain half of the bombs.


Two prototypes with full metal construction were collected in the summer of 1938 a year. The planes were low-wing monoplane with a tapered wing and two floats, podderživavšimisâ conventional N-shaped Struts and diagonal. Two large slotted wing flap was a new feature, adding boarding lift forces and launches from a catapult.


Thanks to the applied design features aircraft iml significant advantage in features compared to the previous sea plane-Scout, that is created by sea plane-Scout Nakajima type 95 (Dave). However, this aircraft lacked the expected Fleet management and sustainability. As a result, these aircraft, known as E12N1, is not interested in the fleet, who stopped in their preferences on competitor Nakajima-Aichi E12A1. The company has considerable confidence in Aichi to E12A1, suggesting that his development as a triple plane. This aircraft became the triple intelligence seaplane type 0 (Aichi E13A1), received from the Allied code Jake and Nakajima E12N1 became the last sea plane-Scout.

A slightly better scan of the Aichi E12A:

Hi! Another image of E12A1.

A nice effort in renaming these topics, Jemiba. However you must understand that "12-Shi" and the likes are just an indication of the year. It can be roughly translated as "12th year" and corresponds to all the tenders issued by the Japanese Navy in 1937. On its own it doesn't mean much... There was a "12-Shi Test Fighter Proposal" competition, a "12-Shi Carrier Fighter" competition, a "12-Shi Land-Based Attack Aircraft" competition, a "12-Shi Two-seat Recce Seaplane" competition, a "12-Shi Three-Seat Recce Seaplane" competition, a "12-Shi Small Reconnaissance Seaplane" competition, a "12-Shi Special Flying Boat" competition and a "12-Shi Primary Trainer Seaplane" competition!

You know, it's not that great an effort to rename topics. We can even start a poll for a more
suitable title ! "IJN 12-Shi Reconnaissance Seaplane Competition 1937 (E12/E13)" would be
better then ?

Jemiba said:

You know, it's not that great an effort to rename topics. We can even start a poll for a more
suitable title ! "IJN 12-Shi Reconnaissance Seaplane Competition 1937 (E12/E13)" would be
better then ?

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Not sure if "IJN" is the most appropriate term for a topic title, given that most people would probably use search terms as "Japan" and "Navy"...

I would suggest something along these lines, but first let's hear alternate suggestions from other forum members:

Japanese Navy 12-Shi Two-seat/Three-Seat Recce Seaplane competitions (E12_/E13_)

Stargazer2006 said:

One easy way of doing things is keeping together the aircraft that were submitted to the same tender (rather than by company).
For Japanese Navy aircraft, it's easy: The letter code for mission type and the number that follows give you that information (for example, E12A, E12K and E12N were Aichi's, Nakajima's and and Kawanishi's submittals to the Navy's 12th "Recce Seaplane" competition).

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Hi. Does anyone have more information on the 12試 複座水上偵察機 12-Shi Two-seat Reconnaissance Seaplane (1937) Kawanishi [E12K]

Mavrick5 said:

Stargazer2006 said:

One easy way of doing things is keeping together the aircraft that were submitted to the same tender (rather than by company).
For Japanese Navy aircraft, it's easy: The letter code for mission type and the number that follows give you that information (for example, E12A, E12K and E12N were Aichi's, Nakajima's and and Kawanishi's submittals to the Navy's 12th "Recce Seaplane" competition).

Click to expand...

Hi. Does anyone have more information on the 12試 複座水上偵察機 12-Shi Two-seat Reconnaissance Seaplane (1937) Kawanishi [E12K]

Click to expand...

I stumbled across this the article yesterday in "NIHON KOKUKI SOSHYU"(Encyclopaedia of Japanese Aircraft) by SHUPAN KYODOSHA, VOLUME 3 KAWANISHI. I am still hoping to find a 3-view drawing if someone can assist.

Cheers

Someone said that there's a name "Raiun" assigned to E13A, but I don't know whether this is true or not

zzy2001 said:

Someone said that there's a name "Raiun" assigned to E13A, but I don't know whether this is true or not

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No,it was called Jak.

hesham said:

No,it was called Jak.

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The Allied reporting name for the Aichi E13A was indeed 'Jake'. But I believe that zzy2001 is trying to confirm the Japanese popular name for the E13A - reported as Raiun (雷雲) meaning something like 'Thundercloud'.

There's a few information left for E12A, including the plan instruction book, a offical-privatal cooperation conference report, a plan requirement from the IJN aviation center, and some testflight reports

Good news!

zzy2001 said:

There's a few information left for E12A, including the plan instruction book, a offical-privatal cooperation conference report, a plan requirement from the IJN aviation center, and some testflight reports

Click to expand...

Excellent.
Are any of the docs available online?

tomo pauk said:

Excellent.
Are any of the docs available online?

Click to expand...

yeah they are , if you want them, please text me individually