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Author Topic: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)  (Read 26549 times)

Offline elmayerle

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Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« on: November 01, 2006, 05:11:53 pm »
Is the Yokosuka Tenga any relation to the R2Y2?   BTW, this engineer is dis-satisfied with most drawings he sees of the R2Y2 with two jet engines buried in the center fuselage above the wing and a nose intake replacing the propeller.  That long an intake would lead to thoroughly nasty inlet losses and flow distortions.  I find the side view from one old French magazine, with podded engines under the wings to be far more plausible.  Now, and advanced R2Y3 with fuselage engines and wingroot intakes I could see, but not what's commonly shown.
« Last Edit: October 18, 2012, 05:30:44 am by Stargazer2006 »

Offline lark

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #1 on: January 17, 2007, 11:11:36 am »
Hesham ,can you show us the sources of your information?

As far as I know , the so called 'Tenga' was not a real project but
only an idea in someone's mind about a jetpowered Ginga variant
but this aircraft was far to heavy for the Japanese jet engines at that time...

Offline hesham

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #2 on: January 19, 2007, 08:29:58 am »
Sorry TsrJoe,

I have no drawings or data to them.

the Yokosuka Tenga became P2Y and there was also anther rocket aircarft
Mizuno Shinryo II .
« Last Edit: March 23, 2007, 11:16:49 am by hesham »

Offline Flitzer

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #3 on: February 07, 2007, 07:13:17 am »
Hi all...
Has anyone any information about the jet powered Kugisho R2Y2?

Was it army or navy?

Any idea of dimensions?

I culled from site the 3 version side view plate and would like to find a top view etc.

Many thanks
Peter
 ;D
"Madness is the normal condition, only interupted by spells of sanity"

Offline hesham

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #4 on: February 07, 2007, 08:44:39 am »
Hi Flitzer,

the Kugisho R2Y2 was developed from R1Y1 and its name Keiun-Kai,
and it can carry one 800 kg bomb,it was designed for Navy of course,
also see;
http://www.j-aircraft.com/artwork/yokosuka_r2y2.htm

Offline elmayerle

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #5 on: February 07, 2007, 10:58:45 am »
Hi Flitzer,

the Kugisho R2Y2 was developed from R1Y1 and its name Keiun-Kai,
and it can carry one 800 kg bomb,it was designed for Navy of course,
also see;
http://www.j-aircraft.com/artwork/yokosuka_r2y2.htm

*chuckle* For what it's worth, I put together the drawings of the R2Y2 that Richard Lewis Mendes used for that artwork.  I'll have to check back on the source article for the drawing, but I always found this engine installation far more plausible than the fuselage-mounted engines with nose inlet that some sources show; the duct losses in that inlet would be unreal, let alone the flow distortions that could occur.

Offline elmayerle

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #6 on: February 07, 2007, 11:00:30 am »
Hi all...
Has anyone any information about the jet powered Kugisho R2Y2?

Was it army or navy?

Any idea of dimensions?

I culled from site the 3 version side view plate and would like to find a top view etc.

Many thanks
Peter
 ;D

From the designation, it was clearly Navy.  If I can find 'em, I'll be glad to supply you with the same data I supplied to Richard Mendes.  Drop me a PM or email if you're interested.

Best,
Evan

Offline Jemiba

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #7 on: February 17, 2007, 01:01:47 pm »
Sorry, I have no top view of the R2Y2, just of the R2Y1, for the R2Y2
it's just a side view. But I think, lenght and span were the same:
span 45ft, 11in, lenght 42ft, 9 1/4in, height 13ft, 9in, wing area
365.973 sq.ft
powerplant were two Ne-330 jet engines of 2.904 pounds thrust,
estimated speed  447 mph, range 2.180 miles at 287 mph, service
ceiling 32.800 ft.
(from RAF Review 04/59)
« Last Edit: February 18, 2007, 03:05:34 am by Jemiba »
It takes a long time, before all mistakes are made ...

Offline elmayerle

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #8 on: February 18, 2007, 10:38:03 pm »
That's basically the side view I have, though mine's taken from a French article.  I'm still digging to find the drawings I made for Richard Mendes, I worked up a 3-view the basic aircraft and then a couple variations in line with other things the IJNAF was doing at the time.  As soon as I can find them, I'll make scans available.

Offline Flitzer

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #9 on: February 20, 2007, 06:06:08 am »
Many many thanks elmayerle.
Great stuff.

I've started a profile for one of the versions...
work in progress. I can't vouch for the accuracy of the camo scheme or markings.

Many thanks again
Peter
"Madness is the normal condition, only interupted by spells of sanity"

Offline elmayerle

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #10 on: February 20, 2007, 01:53:28 pm »
Many many thanks elmayerle.
Great stuff.

I've started a profile for one of the versions...
work in progress. I can't vouch for the accuracy of the camo scheme or markings.

Many thanks again
Peter

The profile you're using is one I have real problems with.  The nose inlet, combined with the engine location, is going to make for very poor engine efficiency between duct losses and inlet distortion.  That's why I think the version shown in Jemiba's profile, with underwing engines, is far more probably.  Now, if you went with wing-root intakes, this engine location would work quite well, but with a nose intake, it's just plain asking for trouble, IMHO.

Offline Flitzer

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #11 on: February 20, 2007, 10:14:22 pm »
Hi elmayerle...

I agree with your comments.
When starting this one, I questioned the nose intake feeding two engines so far back, but this version is labelled as the most likely version that would have been selected for development on the Hikoki 1946 site.

But I hope to do profiles for all versions. The one illustrated just happens to be the first one out of photoshop... ;).

Again the scale views of the wing root intakes and the Me 262-esque underslung engines versions are exactly what I need. Many thanks.

Cheers
Peter
"Madness is the normal condition, only interupted by spells of sanity"

Offline elmayerle

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #12 on: February 21, 2007, 08:19:21 am »
Well, I've often thought that the wing-root intakes of the high-speed versions of the Messerschmitt P.1099/P.1100 designs would be quite applicable here (if one wants to really speculate, a high-speed, swept-wing R2Y3?).  I'm still digging for my three views but I can send you the scanned French article with the side view I started from.  The party who scanned it for me did so in a pcx format; do you have a graphics program that can handle that?  If not, I'll convert to jpgs and send from home tonight.

Offline Flitzer

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #13 on: February 21, 2007, 08:39:35 am »
Again many thanks elmayerle.

You are a real help.

I use an old Mac at work...lunch times of course...so I'm not sure the pcx format will work.
So if you don't mind jpgs would be perfect.

Again many thanks
Peter
"Madness is the normal condition, only interupted by spells of sanity"

Offline elmayerle

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #14 on: February 22, 2007, 10:37:47 am »
Again many thanks elmayerle.

You are a real help.

I use an old Mac at work...lunch times of course...so I'm not sure the pcx format will work.
So if you don't mind jpgs would be perfect.

Again many thanks
Peter


jpg's have been sent.  Scans of the drawings I did will be sent this weekend.  I'll also send an explanation of the variants I schemed up.

Best,
Evan

Offline sagallacci

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #15 on: January 02, 2010, 09:08:06 pm »
Regarding the jet version of the R2Y1, I recall that years ago I saw, in a Japanese publication, a photo and very small/limited detail illustration that proported to be a machine actually built. The photo was of a wreaked fuselage center section with wing root ducts and the illustration was of the engine installation. Of particular note was that the engines were staggered in the fuselage. I'll try to find the material, though I have not seen anything related to that anywhere else.

Offline borovik

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #16 on: January 03, 2010, 02:36:59 pm »
Regarding the jet version of the R2Y1...
sorry, source unknown.
Also on page 3 (Reply # 40), that the same threads have a wonderful color projection P.Allen aka Flitzer.
http://www.secretprojects.co.uk/forum/index.php/topic,661.30.html
Quote
Re: Japanese stuff
« Reply #91 on: August 27, 2008, 12:37:18 am »
Could anybody help me identify these projects?
http://www.secretprojects.co.uk/forum/index.php/topic,661.90.html
Better late than never
Number 4 [Escanear0004.jpg] is the  Kawanishi H11K.  (swallow right)
from: "The XPlanes Of Imperial Japanese Army & Navy 1924-45"
« Last Edit: January 03, 2010, 02:50:44 pm by borovik »

Offline elmayerle

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #17 on: January 14, 2010, 01:21:02 pm »
Regarding the jet version of the R2Y1...
sorry, source unknown.
Also on page 3 (Reply # 40), that the same threads have a wonderful color projection P.Allen aka Flitzer.
http://www.secretprojects.co.uk/forum/index.php/topic,661.30.html
Quote
Re: Japanese stuff
« Reply #91 on: August 27, 2008, 12:37:18 am »
Could anybody help me identify these projects?
http://www.secretprojects.co.uk/forum/index.php/topic,661.90.html
Better late than never
Number 4 [Escanear0004.jpg] is the  Kawanishi H11K.  (swallow right)
from: "The XPlanes Of Imperial Japanese Army & Navy 1924-45"


The R2Y2 with underwing engines or with wing-root intakes are designs that make sense.  The version with a nose intake just doesn't make sense from the duct loses you'd get with the long duct as well as the valuable fuselage "real estate" such a duct takes up.  To my way of thinking, the underwing version would be the easiest and done first, followed by the one with wing-root engines inside the fuselage(note, this also allows you to sweep the wing for a higher-speed version).

Offline Hikoki1946

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #18 on: January 30, 2010, 07:52:20 am »
This is my take as well. Mounting the engines on the wings was simply the most expedient way to equip the R2Y1 with jets. Did the Japanese consider the nose intake idea? I don't doubt they did, especially if one considers the Army design for a single seat jet as put forward by Captain Hayashi which had the engine mounted in the tail with a nose intake, similar to the F-84. But the main issue was the Japanese had no time to fully investigate the effects of long intakes and the Germans likely did not share what research they had on the topic with the Japanese. And even the Germans didn't get the P.1101 off the ground to even validate their research, let alone the Ta 183 making it. If you look at all of the high performance jet aircraft the Germans fielded or flew, all used nacelle mounted engines (Me 262, Ar 234, Ju 287, He 162, He 280). I don't include the He 178 as this was only a technology demonstrator, not a combat aircraft. And if you look at the Japanese jet designs, again, just about all of them used external engines (Tenga, K-200, Kitsuka, R2Y2, the turbojet Gekko project, and the competing Army design for a single jet fighter by Captain Yasuda) with the exceptions of Hayashi's design and the R2Y2 variants and, I imagine, you could lump in the turbojet Oka models.

As for a picture that alludes to showing the jet version of the R2Y1, I'd have to view it with skepticism. I've sometimes seen the photo of the second, incomplete R2Y1 described as having been modified to mount jets but that simply wasn't the case. Even the completed R2Y1 had wing intakes and as the design had rather severe cooling problems, if the second fuselage did have altered wing intakes, it was to cool the Aichi engine, not for jets (not near by library to check!).

Cheers,

Ed



The R2Y2 with underwing engines or with wing-root intakes are designs that make sense.  The version with a nose intake just doesn't make sense from the duct loses you'd get with the long duct as well as the valuable fuselage "real estate" such a duct takes up.  To my way of thinking, the underwing version would be the easiest and done first, followed by the one with wing-root engines inside the fuselage(note, this also allows you to sweep the wing for a higher-speed version).

Offline blackkite

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #19 on: February 02, 2012, 04:47:29 am »
Thanks T-50 san!
Kugisho(空技廠) Keiun(景雲) pictures. Enjoy.


« Last Edit: February 02, 2012, 04:54:33 am by blackkite »

Offline blackkite

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #20 on: February 02, 2012, 04:52:44 am »
Next pictures.
Kugisho engineers called her Okeichan(お景ちゃん).

Offline Skyblazer

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #21 on: February 02, 2012, 07:23:17 am »
Kugisho engineers called her Okeichan(お景ちゃん).

Which means... ?

Offline T-50

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #22 on: February 02, 2012, 03:06:14 pm »
Hi blackkite san you did it again! I didnt know there were more pics about the beatiful cloud!I thought the war has destroyed most of the pics.
Im glad there are more surviving pics of this again very extraordinaire plane,I know there were plans to reequip this plane with jet engines
thanks again to share this rare photo material with us!
cheers
T-50

Offline blackkite

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #23 on: February 02, 2012, 03:29:02 pm »
Kugisho engineers called her Okeichan(お景ちゃん).

Which means... ?

Keiun is 景雲.
景 means scenery. 雲 is cloud.
In Japan, we use letter 景 for woman's name. For example 景子(keiko).
子 means child. Many Japanese women have this letter 子 for her name. For example 雅子(Masako, the name of Japanese princess name as you know).
Okeichan is Keiko's pet name. Generally 景子 are very beautiful girls. ;D For example Keiko Takeshita.

http://talent.yahoo.co.jp/pf/detail/pp2714

http://search.babylon.com/?s=img&babsrc=HP_ss&q=%E9%9B%85%E5%AD%90%E5%A6%83
« Last Edit: February 02, 2012, 05:14:36 pm by blackkite »

Offline Skyblazer

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #24 on: February 02, 2012, 03:48:09 pm »
Thanks for the explanations! So what is the word "onna", then? I thought that was the word for woman...

Offline blackkite

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #25 on: February 02, 2012, 03:51:58 pm »
Onna(woman) is 女. Man is otoko(男).

Offline Justo Miranda

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #26 on: February 03, 2012, 06:52:54 am »
Keiun additional info

Offline hesham

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #27 on: February 03, 2012, 01:43:08 pm »
 Excellent my dear Justo.

Offline blackkite

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #28 on: February 03, 2012, 03:15:17 pm »
Wow beautiful Okeichan !! ;)
« Last Edit: February 03, 2012, 05:09:36 pm by blackkite »

Offline windswords

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #29 on: February 03, 2012, 05:29:29 pm »
Why in the jet proposal (R2Y2) are the Keiun's engines offset? Wouldn't that create a weight imbalance as well as a thrust imbalance?  ???
Frank

Offline Alcides

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #30 on: February 03, 2012, 08:18:39 pm »
blackkite, Just thanks a lot for the pictures. They're great.  :D :D :D

Offline Flitzer

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #31 on: February 04, 2012, 12:12:22 am »
A few profiles...
"Madness is the normal condition, only interupted by spells of sanity"

Offline fockewulf261

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #32 on: February 04, 2012, 12:57:31 pm »
Hi, Flitzer.  I noticed that the R2Y2 is described as a twinengined fighter.  But in the specs you gave it one engine.

Offline blackkite

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #33 on: February 04, 2012, 03:29:31 pm »
Why in the jet proposal (R2Y2) are the Keiun's engines offset? Wouldn't that create a weight imbalance as well as a thrust imbalance?  ???


Hi! I think that the purpose of offset engine is to reduce fuselage cross section area. Small fuselage cross section area resulted low drag.
« Last Edit: February 04, 2012, 03:46:45 pm by blackkite »

Offline blackkite

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #34 on: May 23, 2012, 03:52:37 am »
(Part 1)
In 1941, Kugisho planned land base strategic reconnaissance aircraft as 17-shi land base reconnaissance aircraft(Y30, R1Y1). (Y10: Suisei(彗星), Y20 : Ginga(銀河)).
Kugisho Y30 (暁雲,Gyoun: the morning cloud) specification was as follows.
Engine : Mitsubishi ME2A H shape 24 cylinders liquid cooling engine×2(side by side) with steam turbine drive forced cooling fan, total 5000hp.
Propeller : single propeller, Maximum speed : 360kt(667km/h/6000m), Cruising speed : 250kt(463km/h/4000m), Range : 4000n.m.(7400km at cruising speed) .
Finally Y30 with ME2A engine was abandoned because it's difficult to realize such a radical plan, forward view was bad and did not fulfill required performance.

Then twin propeller aircraft which use two Mitsubishi MK10A engine(2400hp) was planned as Y30. Planned performance was as follows.
Maximum speed : 350kt(648km/h/6000m), 370kt(685km/h/8000m),(while required maximum speed top was 360kt(667km/h/6000m)
The IJN rejected this plan, because Y30 with MK10A did not fulfill the IJN's maximum speed requirement. Y30 with MK10A had a Ginga like shape, and more smart. Also MA10A engine had many problems.
« Last Edit: May 23, 2012, 07:28:14 pm by blackkite »

Offline blackkite

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #35 on: May 23, 2012, 05:18:30 am »
(Part 2)
Finally commander Masao Yamana of Kugisho offered following plan based on imported He119 bomber.
Engine : Aichi Atsuta AE1T(DB601 series), take off power 1,700hp×2(side by side),
Maximum speed : 390kt(722km/h/10000m), Range : 1800n.m.(3300km/250kt(4000m))
Pressurized cabin, With turbo charger, 3.9m Extended propeller shaft, Single propeller, Wing loading : 238kg/square meter,
The IJN ordered Kugisho to develop this plan as Y40 Keiun (R2Y1). But it's difficult for Kugisho to continue development of Y40, because Kugisho's engineers were very busy to solve existing new planes problems.
At the time, Japan got jet engine technology from Germany, Kugisho offered jet powered Keiun-kai plan to the IJN. Keiun-kai's specification were as follows.
Engine : Mitsubishi Ne330 turbo jet engine(thrust 1320kg)×2, Maximum speed at S.L. 430kt(796km/h), Range 650n.m.(1300km)     
The IJN ordered Kugisho to develop jet powered Keiun-kai as R2Y2 immediately.
Kugisho also offered to continue development of R2Y1 Keiun to get technical data for R2Y2, and  the IJN agreed this offer.
« Last Edit: May 23, 2012, 07:30:11 pm by blackkite »

Offline blackkite

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #36 on: May 23, 2012, 07:27:09 pm »
(Part3)
In May 1945, Kugisho completed Keiun without pressurized cabin and turbocharger by rush work, transferred Keiun from Yokosuka(横須賀) factory to Kisarazu(木更津) base for flight test.
In the ground test, W shape engine's inner cylinders and oil temperature increased excessively, temporally air inlets were added one by one. In 29th of May, when the first flight, rapid oil temperature increase and engine bay fire happened, made emergency landing after only one turn above the runway. Very big air scoop was added to Keiun after this accident. In 31th of May, when engine ground test, engine stick happened by mistake, let Keiun alone until the end of the war. After the war, the U.S. Wanted Keiun, they had a one picture of Keiun, but Keiun was already exploded by the IJN's indiscriminate explosion team.
http://gunsight.jp/c/keiun-3D.htm
« Last Edit: May 24, 2012, 04:28:01 pm by blackkite »

Offline Justo Miranda

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #37 on: May 26, 2012, 11:31:42 am »
Hi  :)

Offline Justo Miranda

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #38 on: May 26, 2012, 12:04:21 pm »
 :) :)

Offline Flitzer

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #39 on: May 26, 2012, 03:01:18 pm »
Thought these might be of some use.


P :)
"Madness is the normal condition, only interupted by spells of sanity"

Offline blackkite

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #40 on: May 26, 2012, 04:51:33 pm »
Many thanks Justo and Flitzer! :D
Yes Keiun-kai's initial plan air intake were located at wing leading edge or radiator air intake position of Keiun.
Later the air intake was moved to nose for better efficiency.
Pressure drop of engine intake air through straight and large diameter duct was small.
« Last Edit: May 27, 2012, 12:32:15 am by blackkite »

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #41 on: May 27, 2012, 09:29:53 pm »
Hi! Keiun air intakes. ;D
No.1 Keiun had no turbocharger and inter cooler. Those development were delayed.
The oil coolers were located at the wing root leading edge.
« Last Edit: May 28, 2012, 03:45:20 am by blackkite »

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #42 on: October 18, 2012, 05:31:34 am »
New topic split from the "Japanese Projects before 1945" thread... A few repeats here, so feel free to edit your posts to keep the best quality pics.

Offline blackkite

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #44 on: February 02, 2014, 11:53:14 am »
A lot of really great info in this thread, but it all still fails to answer my nagging question.  :-\
Since the R2Y1 Keiun was designed as a reconnaissance plane, where were the cameras supposed to be, as well as the camera windows? I want to build a model of it, but I don't like building models of photo-reconnaissance aircraft, without camera windows.
 
Larry
 

Offline blackkite

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #45 on: February 02, 2014, 03:08:49 pm »
Hi! Camera window.
写真撮影用窓 : Camera window.
« Last Edit: February 02, 2014, 03:10:24 pm by blackkite »

Offline ReccePhreak

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #46 on: February 02, 2014, 05:42:51 pm »
Thank you SO MUCH!!  ;D
I can now continue working on my model.
 
Larry

Offline blackkite

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #47 on: February 02, 2014, 08:06:45 pm »
Good luck to you. Let's meet modeling forum near future. ;)
 
通信・偵察員出入口兼窓 : Communication  and reconnaissance member entrance and window
« Last Edit: February 02, 2014, 08:17:41 pm by blackkite »

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #48 on: October 17, 2014, 05:25:43 am »
The Yokosuka R2Y2.

Offline blackkite

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #49 on: October 17, 2014, 03:33:21 pm »
Hi! Another image of Keiun-kai.

Offline Justo Miranda

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #50 on: October 17, 2014, 03:40:54 pm »
Hi  ;)

Offline blackkite

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #51 on: October 17, 2014, 09:54:32 pm »
Wow thanks a lot. ;) :D
« Last Edit: October 17, 2014, 11:17:27 pm by blackkite »

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #52 on: October 19, 2014, 10:34:08 am »
that's a awesome picture Blackkite san,and the topic is getting more and more interesting!

Offline lark

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #53 on: October 19, 2014, 12:19:55 pm »
Blackkite , is that a projected nightfighter variant in your #49 post ?

Offline blackkite

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #54 on: October 19, 2014, 04:58:35 pm »
Hi! I believe it's a recon.
http://plaza.rakuten.co.jp/zerotagucci/diary/201302120000/

Thes author of this site said that,
"I created the imaginary picture of Keiun-kai, having assumed that a Japanese army continued fighting the 1945 late autumn or subsequent ones.
What it referred to is the aviation unknown episode in separate volume of Aireview magazine and the memo of a lieutenant colonel Otsuki (大築中佐) of those days in the history of Japanese aviation which Japan Society for Aeronautical and Space Sciences edited.
Equipped engine was Ne330 jet ngine.
The maximal speed was 430 nautical miles/h.
Because fuel consumption of Ne330 jet engine was very large, if 330 jet engines were equipped in the body, the space which stores a fuel tank will be lost.
Therefore, wings were equipped with the jet engine. "

So I can't identify that this drawing shows whether nighter fighter or recon.
There are radar antenna in this drawing, this drawing may be shows night fighter, but Ican't find weapon. ??? Some kind of AEW or ship detection??
« Last Edit: October 20, 2014, 06:34:02 pm by blackkite »

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #55 on: October 20, 2014, 04:21:16 am »
Hi Justo!

Is this from an Unknown! Issue? Or what is the source of your very good drawing?

Greetings

P.S.: Can´t wait till the "Ultimate Flying wings" will be published.

Offline blackkite

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #57 on: October 20, 2014, 09:17:07 pm »
... but Ican't find weapon. ??? Some kind of AEW or ship detection??

Could be a radar set similar to the FuG 200 Hohentwiel, of course, that was fitted to German maritime
recce aircraft like the Fw 200. Those lateral antennas at the rear fuselage may be an additional clue,
I think. But to my opinion, a jet aircraft of that size and era would have had too short a range to be
of much use for that kind of reconnaissance, especially as staying in touch quite probably would have
be vital. Weapons for a nightfighter version could be placed in a weapons pack under the fuselage,
I think.
It takes a long time, before all mistakes are made ...

Offline Justo Miranda

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #58 on: October 20, 2014, 10:38:57 pm »
Hi Justo!

Is this from an Unknown! Issue? Or what is the source of your very good drawing?

Greetings

P.S.: Can´t wait till the "Ultimate Flying wings" will be published.


From my next book "Axis suicide squads: German and Japanese Secret Projects of the Second World War"

Offline blackkite

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #59 on: October 21, 2014, 04:46:42 am »
Wow super news again!!

Although it was used in the navy, having diverted the ship airplane also to reconnaissance on a land base, It interfered with strategy by not having an exclusive reconnaissance plane by battle on the vast China continent, and the 17 shi land reconnaissance plane "Gyoun" (R1Y1) was inaugurated as the plan Y30 in Kugisho in the plan by the combat lesson in the Showa 16 fiscal year as a full-scale land reconnaissance plane in which long-distance forcible reconnaissance is possible. However, it would ride on the victory of the beginning of a game, as for this machine with which too much high performance was demanded, necessity would also fade by sudden change of the war situation, a small aircraft in which forcible reconnaissance is possible will come to be desired by high altitude, and the plan Y30 will be called off after all. Although Y40 aiming at the high altitude forcible reconnaissance which should be replaced with these Y30 is the same, the first design was started by the Masao Yamana technical lieutenant colonel and the plan was furthered after that as an 18 shi land reconnaissance plane "Keiun" (R2Y1) by Kugisho in Showa 18(1943) by making  Yukio Otsuki technical lieutenant colonel into a specialist designer, The performance which the navy authorities demand was  that the maximal speed of 400 knots (740 km/h) faster than any operating fighter at the day, and the cruising range of 2,000 nautical miles (3,700 km).
The design of keiun was based on Heinkel He119, to equip fuselage mid-section with Ha 70-01 (A23 twins type) which combined two Aichi Atsuta 30 type water cooled engine in parallel, and had contra rotating three blade propeller at the nose of an airplane which were rotated by 4m length extended shaft. It was presupposed that there was a difficulty also technically and an unusual form like a single-engine plane was calmly adopted as 6 blade propeller at a glance also from the practical aspect.  
The fuselage had simple thick plate stress skin structure, new mechanisms, such as an integral tank of special structure adoption, a triad landing gear, and thin wings for high-speed, were tried, and since it was an object for high altitude, equipment of the turbocharger and the pressurized cabin was planned.
However, the trial production stop was determined in the autumn of Showa 19 (1944) by the model reduction by war situation urgency.
However, "Keiun-kai" (R2Y2) which equipped with two Ne330 turbojet engine, and it converts into a high speed attack and a bomber was planned, and the No. 1 trial production of "Keiun" completed by Kugisho in April, Showa 20 (1945) in order to obtain the data for Keiun-kai.
The first flight test carried out without turbocharger, because of turbocharger manufacture delay.
But, when the second test flight May 1945, the twin type "Atsuta" engine damage by fire of the engine, and has been destroyed by the air raid at the Kisarazu airfield late in July while preparing replacement of the engine.
In the time to require an emergency in wartime, criticism that having forced development of the airplane which has many problems also technically like Keiun has resulted in wasting the labor of group of technical experts in vain cannot be denied.

Gyoun(暁雲) means dawn clouds. Clouds at dawn.
Saiun(彩雲) means (rainbow) colored clouds.
« Last Edit: October 21, 2014, 08:01:22 pm by blackkite »

Offline Johnbr

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #60 on: August 31, 2017, 05:47:35 am »
 :)

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #61 on: August 31, 2017, 06:41:37 am »
This photo has seen for the first time. :o Thanks a lot. :D

Offline Justo Miranda

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #62 on: August 31, 2017, 02:19:36 pm »
Thanks a lot :)

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #63 on: August 21, 2018, 08:49:16 am »





some illustration of the R2Y2 keiun-kai.

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #64 on: August 21, 2018, 08:53:23 am »
another nice one:

Offline Retired In Kalifornia

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #65 on: August 21, 2018, 09:15:18 am »

some illustration of the R2Y2 keiun-kai.
This is one of my early art renderings J-Aircraft posted in 1998 rendered with Micrografx Draw 5. Admittedly very crude but in 1998 there still wasn't whole lot up on the Internet in way of original produced digital aviation art. Much 3-D aviation art has been rendered & posted on the Internet so don't know whether I'll produce any more 2-D portraiture pieces.

Offline sgeorges4

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #66 on: August 21, 2018, 09:44:34 am »
Did someone has a real drawing regarding the jet variant(Keiun-kai) or not? If not,all the illustration are artist impression about what was really planned right?
Sorry for my english.

Offline Retired In Kalifornia

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #67 on: August 21, 2018, 04:43:16 pm »
Did someone has a real drawing regarding the jet variant(Keiun-kai) or not? If not,all the illustration are artist impression about what was really planned right?
Sorry for my english.
My art was based on "interpretive drawings" given to me by a retired aerospace engineer interested in WWII Japanese aircraft over 20 years ago. Whether there were genuine Japanese drawings of Keiun-kai variants I definitely can't say. others here at Secret Projects hopefully will help y'all out here.

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Re: Yokosuka (Kugisho) « Keiun » (R2Y1) and « Keiun-kai » (R2Y2)
« Reply #68 on: October 22, 2018, 05:58:13 pm »
 :)
« Last Edit: October 22, 2018, 06:20:09 pm by Johnbr »