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A French-made Junkers Ju 252, with Hispano-Suiza engines?

Started by Default Setting, January 06, 2019, 12:11:57 PM

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Default Setting

During WW2, French aircraft manufacturer Amiot produced several hundred Junkers Ju 52 for the German war effort, and after the war continued producing identical aircraft--now renamed Amiot AAC.1 Toucan--for the Armée de l'Air. Meanwhile, in Germany itself, production of the newer Ju 252 stopped after only 15 had been assembled, and Junkers was instructed to instead produce the 352, which required fewer strategic materials.

So what if, instead of canceling the 252, Germany had licensed its production to Amiot, either in supplement to, or instead of, the Ju 52? As was the case OTL for the 52, Amiot could have gone on producing the 252 after the war under its own name, giving the plane a further lease on life.

A related query is whether, as an extra measure of economy, the French-made 252 might have been fitted with locally available Hispano-Suiza 12Y powerplants? It wouldn't have been the only German plane using French engines--the Messerschmitt Me 323 Gigant comes to mind.

Does anyone fancy dressing the 252 in 1945 French colors?
The one duty we owe to history is to rewrite it.
-- Oscar Wilde

rickshaw

Production of the 252 was stopped on economic reasons - they decided it used too much metal and so forced Junkers to redesign it in largely timber as the 352.   Now, unless France has, in 1943-44, access to some unknown source of aluminium and other metals, I really cannot see this happening under German control.  The 352 might be a better choice...

The engines are an interesting choice though, I'll admit.   I think though, the SNECMA 14R (originally Gnome-Rhône 14R) radial engine would be a better choice than the Hispano-Suiza 12Y.
How to reduce carbon emissions - Tip #1 - Walk to the Bar for drinks.

The Wooksta!

I don't do ANYTHING in French markings.

352 is definitely a better idea for manufacture but captured 252s is certainly possible, although I don't think there were any by the end of the war.  There were at least two 352s flying post war - one with the RAF and another with the Czechs.

Spanish, Swedish or Finnish markings are also possible.
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Default Setting

Quote from: rickshaw on January 06, 2019, 02:23:53 PM
Production of the 252 was stopped on economic reasons - they decided it used too much metal and so forced Junkers to redesign it in largely timber as the 352.   Now, unless France has, in 1943-44, access to some unknown source of aluminium and other metals, I really cannot see this happening under German control.  The 352 might be a better choice...

Well, France did produce a few hundred all-metal Ju 52, so the materials were there, they could simply be reallocated to the production of the more advanced plane. But we can certainly imagine that Amiot is instructed to go with the 352 on top of its 52 production line. Whichever is more plausible.

Quote from: rickshaw on January 06, 2019, 02:23:53 PMengines are an interesting choice though, I'll admit.   I think though, the SNECMA 14R (originally Gnome-Rhône 14R) radial engine would be a better choice than the Hispano-Suiza 12Y.

For the engines, I figured that the 12Y is the closest thing in the French inventory to the original BMW Jumo 211F, but the 14R is definitely a possibility as well. I'll defer to those with more expertise than I have on vintage powerplants.
The one duty we owe to history is to rewrite it.
-- Oscar Wilde

zenrat

If one says it uses the Hispaniel-Suiza engines one could utilise the nacelles from a Pe2 as they were powered by the Klimov version of the 12Y.
Fred

- Can't be bothered to do the proper research and get it right.

Another ill conceived, lazily thought out, crudely executed and badly painted piece of half arsed what-if modelling muppetry from zenrat industries.

zenrat industries:  We're everywhere...for your convenience..

The Wooksta!

AFAIK, there isn't a kit of the Ju 252.  Airmodel *might* have done one in vacform - they definitely did the 352 as I've got one somewhere, as did Mach Poo.
"It's basically a cure -  for not being an axe-wielding homicidal maniac. The potential market's enormous!"

"Visit Scarfolk today!"
https://scarfolk.blogspot.com/

"Dance, dance, dance, dance, dance to the radio!"

The Plan:
www.whatifmodelers.com/index.php/topic

rickshaw

Quote from: Default Setting on January 06, 2019, 10:15:47 PM
Quote from: rickshaw on January 06, 2019, 02:23:53 PM
Production of the 252 was stopped on economic reasons - they decided it used too much metal and so forced Junkers to redesign it in largely timber as the 352.   Now, unless France has, in 1943-44, access to some unknown source of aluminium and other metals, I really cannot see this happening under German control.  The 352 might be a better choice...

Well, France did produce a few hundred all-metal Ju 52, so the materials were there, they could simply be reallocated to the production of the more advanced plane. But we can certainly imagine that Amiot is instructed to go with the 352 on top of its 52 production line. Whichever is more plausible.

Quote from: rickshaw on January 06, 2019, 02:23:53 PMengines are an interesting choice though, I'll admit.   I think though, the SNECMA 14R (originally Gnome-Rhône 14R) radial engine would be a better choice than the Hispano-Suiza 12Y.

For the engines, I figured that the 12Y is the closest thing in the French inventory to the original BMW Jumo 211F, but the 14R is definitely a possibility as well. I'll defer to those with more expertise than I have on vintage powerplants.

The Jumo 211f was rated at 1,322 hp (I assume on take off).  It was produced by Junkers, not BMW.
The SNECMA 14R was rated at 1,590 hp
Hispano-Suiza 12Y was rated at 1,000 hp in it's most developed version.

The 12Y was less powerful than the 211.  The 14R was more powerful.  Personally, I've always believed the more power from an engine, the better off the aircraft will perform.

The Jumo 211f weighed 1,290 lb
The SNECMA 14R weighed 1,805.59 lb
Hispano-Suiza 12Y weighed 1,135 lb

Of the three, the 14R is definitely the heaviest.  Followed by the 12Y and finally by the 211.

Mach 2 does do an injection 252 model in 1/72.  Airmodel does a vacuform 352 in 1/72.

How to reduce carbon emissions - Tip #1 - Walk to the Bar for drinks.

The Wooksta!

Mach 2 does the Ju 352 - I have one in the stash.  Combat models apparently did a 252 circa 1999, whether it's still available, I don't know.

http://www.hugojunkers.bplaced.net/junkers-ju252-ju352-model-kits.html

Interesting article using bothe Mach Poo and Airmodel kits:
https://modellersofballarat.wordpress.com/articles/aircraft/escape-to-denmark-172-junkers-ju-352-herkules/
"It's basically a cure -  for not being an axe-wielding homicidal maniac. The potential market's enormous!"

"Visit Scarfolk today!"
https://scarfolk.blogspot.com/

"Dance, dance, dance, dance, dance to the radio!"

The Plan:
www.whatifmodelers.com/index.php/topic

Default Setting

Quote from: rickshaw on January 07, 2019, 04:39:45 AM
The 12Y was less powerful than the 211.  The 14R was more powerful.  Personally, I've always believed the more power from an engine, the better off the aircraft will perform.

What might the Ju 252 look like with 14R engines? I'm assuming shortier and stubbier engine nacelles?
The one duty we owe to history is to rewrite it.
-- Oscar Wilde

rickshaw

Quote from: Default Setting on January 11, 2019, 07:26:32 AM
Quote from: rickshaw on January 07, 2019, 04:39:45 AM
The 12Y was less powerful than the 211.  The 14R was more powerful.  Personally, I've always believed the more power from an engine, the better off the aircraft will perform.

What might the Ju 252 look like with 14R engines? I'm assuming shortier and stubbier engine nacelles?

Wide, shorter, stubbier engine nacelles, which are circular (although the annular radiators on the Jumo 211 installation are also circular).

The 14R was Length: 1,635 mm (64.37 in)
                      Diameter: 1,297 mm (51.06 in)

The Jumo 211 was Length: 1,768 mm (69.61 in)
                                Width: 804 mm (31.65 in)
                                Height: 1,050 mm (41.34 in)

How to reduce carbon emissions - Tip #1 - Walk to the Bar for drinks.

jcf

The Bramo 323 installation of the 352 is probably your best guide as to appearance of
a roughly similar sized radial installation. The real world difference in engine diameter
makes no difference on a model.

Default Setting

I'm coming back to this because it dawned on me that an incentive for Junkers to try and fit 12Y engines on the 252, was the fact that they were being produced under license in Czechoslovakia before the war. I'm not sure if production continued after the German annexation (can someone confirm?) but assuming it does, that would be a good way to alleviate pressure on domestic German powerplant production. Of course, French-made 252s would get locally produced 12Y engines.

Quote from: rickshaw on January 07, 2019, 04:39:45 AM
The 12Y was less powerful than the 211.  The 14R was more powerful.  Personally, I've always believed the more power from an engine, the better off the aircraft will perform.
What would be the loss of performance? Would it still somewhere in the ballpark of the inferior 352?
The one duty we owe to history is to rewrite it.
-- Oscar Wilde

jcf

Going back to engine performance, hp/lb is the important metric.

12Y: .88hp/lb
14R: .88hp/lb
211: 1.02hp/lb

Performance is a wash between the two French engines.

Default Setting

Quote from: joncarrfarrelly on July 19, 2019, 01:20:08 PM
Going back to engine performance, hp/lb is the important metric.
So, as a rough estimate, are we looking at a 15-20% performance loss in terms of top speed, range and/or payload compared with the original Jumo-powered version?
The one duty we owe to history is to rewrite it.
-- Oscar Wilde