Data Base: Japanese Aircraft Engines

[Shinpachi]

Yesterday, I happened to come across a copy of book which I had been longing for...."Engine of Tragedy Homare". With no hesitation, I bought it.

Though I must read page by page, roughly checking, 70 percent of the content seems overlapping with the book "Engine History of Nakajima Aircraft" I introduced last time.

As attached pics show, coolant system problem attracts my attention.
Details are going to follow soon.
Thanks.

 

[vikingBerserker]

Just beautiful book!. I love the way Japanese writing looks.

 

[Shinpachi]

Hi, vikingBerserker. Thanks!

 

[Aurum]

It starts with Nakajima's. pdf file attached.
I hope our local publisher won't claim their copyright as this is a private forum of membership.

They are all writen in Japanese, so -
1. Posting is one thing.
2. Translation is another.

Finding time, I'm going to translate them point to point.

This book "Engine History of Nakajima Aircraft (265pages in total)" consists of two main parts.
Development history is described on the former half with many engine photos.
Memories, recollections and testimonies of the former engineers occupies the latter half with almost no photos.

I introduce the photos from the former part and the chronological table of engine development history along with the full engine lists of Nakajima from the latter half to refile to 54 pages.

Publication of this book was discontinued twenty years ago, so I believe this is a rare opportunity to check its contents.

Please enjoy.

Thank you Shinpachi very much for presenting this quite rare too interesting book.
Thanks for translating the table of Nakajima engines projects.
Could I ask you to make a favor and translate the Timetable of Nakajima activity that is on pp. 248-259 of this book. I hope it could take not so mush time and guess that important info regarding WWII starts appoximately from 1920-ie so pp/ 248-251 could be missed.

And also I would like to understand what had happen with Nakajima water-cooled V12 engine projects. In p.1 of the table you been kind to translate there are several of them together with some W18 in-line engine projects. As it could be seen, general characteristics of Nak V12 were not worse then their European contemporaries. So why Nakajima did not realized any of them?

 

[Shinpachi]

The long camshaft for the in-line engines requires the highest precision of such one tenth micron meters but Japan had no sufficient technology, that is, highest-precision machineries to manufacure the part on the massproduction basis. Such important parts were all handmade in those days.

Therefore, IJA, above all, did not pay attention to the liquid-cooled engines at all though they ironically had to pay it later when they understood that they would need it immediately to intercept the super hi-altitude bomber B-29. Completed technology of DB-601 was imported from Germany but everything was too late.

However, there was one chance for Nakajima Aircraft to produce W18 engine(NLH11 Ha-39) because one of their engine designers Hiroshi Takeshima who had already completed his V12 NWE as Ha-15 was so enthusiastic about the development of the liquid-cooled engines.

It was to be produced in their new factory in Ohmiya from 1944.

He had completed NLH11 as Ha-39 by June 1941.
This 1st prototype was very good but broken during the running test because a worker had forgot to pour coolant liquid carelessly. He began to manufacture 2nd prototype but Japan had got into the Pacific War and Nakajima Aircraft had no choice but gave up the liquid-cooled engines.

The new Ohmiya factory was used for the production of double-row 18-cylinder radial engine 'Homare' afterward.

Thanks Aurum for your interest to the history of Nakajima but sorry I have no time to translate the timetable so soon at the moment. I'll try to make it in a few weeks immediately, though.
Please be patient for a while.

Thanks.

 

[Ivan1GFP]

Hi Shinpachi,

I hadn't followed this thread for a while, but here is a link to check out:

http://www.warbirdsite.com/Japanese compass.jpg

Looks pretty close to me.
- Ivan.

 

[Shinpachi]

Ah, Ivan. That is an answer to the photo I asked last year.
Then, the compass holder would be possibly the part of Nakajima B5N "Kate" found on the Shumshu Island together with the engine cowl!

You are very expert of research!
Thank you very much!!!

 

[Aurum]

...
However, there was one chance for Nakajima Aircraft to produce W18 engine(NLH11 Ha-39) because one of their engine designers Hiroshi Takeshima who had already completed his V12 NWE as Ha-15 was so enthusiastic about the development of the liquid-cooled engines.
...

Yes, its interesting fact that in the end of 30-ies such engines of W18 scheme were designed. It should look like Hiro 91 type engine i.e. 6 cylinders in block in 3 raws. But it was also Y-type configuration?
I think this project was competitor not to Homare that was small fighter's engine, but to Mamori that was large heavy bomber's engine specially designed for G5N Shinzan B6N Tenzan.
So if Ha-39 had appeared, it could be installed on these aircrafts.

Besides Ha-15 Ha-39 there is one more interesting up-to-date NWD engine. This inverted V12 was designed for NAVY by Yoshimasa Tanaka in 1933-35 that is rather earlier then Ha-15. 2 prototypes were built. It had sufficient volume 41L so in case of progressing it could rich ~1500-1600 hp from initial 900-1050 hp. Seems it could be even better than licensed DB 601 it's boosted variants.
Its great regret that Japanese own liquid cooled engines did not entered mass production. But on the other side DBies was not extrimly critical for aviation too.

You have described some hardships that were to overcome for mass production of large in-line engines, but I could you remember that Soviet Union were almost in the same situation. SU did not possess modern technologies so might to by license for Hispano-Suisa in mid 1930ies. But never the less SU developed and redesigned independently BMW-IV that transformed into mighty AM-37/39/42 engine that corresponds to DB 603. Without this engine the most numbered so main Russian attack plane Il-2 could not flight.

Thanks for your reply on my asking you to translate the Nakajima timetable. I hope wish you to have some little time for it's translation though in it's most interesting parts.

Best regards

 

[Micdrow]

Hi Shinpachi,

I hadn't followed this thread for a while, but here is a link to check out:

http://www.warbirdsite.com/Japanese compass.jpg

Looks pretty close to me.
- Ivan.

Great find there Ivan!!!

 

[Ivan1GFP]

Thanks Shinpachi, Micdrow,

My search was easy since I was pretty sure it was a compass mounting because of the bronze / brass appearance.

- Ivan.

 

[Shinpachi]

I said the part is of Nakajima B5N "Kate" found on the Shumshu Island but further research shows ... with my apology that...as follows.

It has turned out that the compass was Army "Type 2 Model 2" which was manufactured by Tokyo Aviation Instruments and equipped by Type 97 Heavy Bomber "Sally" and Type 99 Light Bomber "Lily". The mount relic I asked is thought recovered after the Nomonhan Incident(Battle of Nomonhan May-Sept 1939).

Thanks again for your information, Ivan.
You are a very expert of research!

 

[Armchair Ace]

簡単には手に入らない情報が入っていてとっても興味深い本ですね！

どうもありがとうございます！

 

[Shinpachi]

ここは英語で行きます。。。
Here I go with English...

Thanks for your interest to the Nakajima book. Right, those informations are hard to come by nowadays.
You are welcome, Armchair Ace!

 

[Shinpachi]

I have obtained the book "The History of Mitsubishi Aero-Engines" at last.

Does anyone help me with translation for English?
The lists of about twenty pages would interest the researchers.

I must admit myself that I have no time for it anymore at all.
If someone might be interested, please help. Thanks.

 

[Vincenzo]

unlucky idk japanese (and i know very bad english), but i've sure interest at tables like nakajima engines, the use of automatic translator it's not applicable?

 

[Shinpachi]

Thanks for your care and suggestion, Vincenzo.
I believe you are one of the kindest persons, like other members here, in the world!

Sorry but the automatic translator makes no sense for the printed words at the moment because I have to type the Japanese language by handwork before apply it.

I'm going to translate them by myself after all.
What I wish is to introduce those rare data as soon as possible for the members because here are tons of such informations.

Thanks again, Vincenzo, for your care

 

[Vincenzo]

thank you for the kindest.
idk if this it's applicable for japanese but you can't save pdf in a text format and after use the translator?

 

[Shinpachi]

Thanks for your advice, Vincenzo, but there is regretly no text information when the pdf file is made from a printed matter.
It's same as a photo...

 

[Vincenzo]

unlucky i suppose that you haven't a scanner (or a multifunction printer with a scanner mode)
so need as you tell (translate from yourself)

 

[Shinpachi]

I have a scanner...then,
OK, Vincenzo

I was forgetting a miracle tool - image-text converter though it has many reading errors but I will check which is better and quicker, manual translation or machine translation.

Thanks!