Cloning?

[Lucky13]

Ha! Threw you off the trcak there, didn't I?

Was just thinking, with all the aircraft kindly snapped up by the Luftwaffe (who would say no to a free aircraft?) during the war...
How difficult would it have been for them, BMW, Junkers and others to clone the engines to be used in there own creations?
What difference would it have made with a Ju-88, Bf-110 or '410 with Merlins or even a '190 with the same engine as the '47? Would it have been possible?
How different was the quality of work between these engines and others?

 

[Elmas]

Just think to the threads af all the screws, ball bearings, general measures etc. to "translate" from Imperial (American...) to Metric......
It was not possible......al least with the time that the Third Reich did not have: it was a very scarce raw material, then.
The Russians succedeed with the B29: but they did not have flocks of B17 above their heads......

 

[davebender]

R2800 radial was the only Allied engine clearly superior to anything made in Germany. I doubt Germany acquired one before 1943. By then it's too late to matter. Like the Soviet B-29 clone, the German R2800 clone won't be operational until after 1945.

 

[Shortround6]

Even the Americans could take 1 1/2 to 2 years to set up a factory and getting it turning out large numbers of engines starting from a bare plot of ground BUT starting WITH the help of a complete set of blueprints of the engine, Some parts supplied by outside vendors (laready making parts for parent company) AND the help of some engineers from the parent factory/s.

There are two stories on the engines for the Russian TU-4, one is that they copied the engines in teh B-29 and the other is that they used their own engines in it, only part/s not copied.

But since their own engine was a 2 row 18 cylinder developed of a licence built 9 cylinder 1 row Wright Cyclone and the R-3350 was a Wright developed 2 row 18 cylinder version of the 9 cylinder 1 row Wright Cyclone the practical difference is vary small.
The Russian 2 row 18 cylinder engine was the 4th attempt at such an 18 cylinder engine by the same design team and the 9 cylinder Licence built engines had already been "Metricized".

 

[Balljoint]

How long did it take Packard to clone the Merlin? That would be a best cse starting point.

 

[Shortround6]

Deal was signed in Sept of 1940. Packard delivered 45 (?)engines in 1941, 2 in the summer which may have used some R-R supplied parts , 4 in Sept, 5 in Oct, 10 in Nov, 26 in Dec and going to 109 in Jan, 149 in Feb, 333 in March and 505 in April, By July 1942 they were over 800 a month.

Cloning also depends on the ability of subcontractors to supply parts (bearings) or on casting and foundry techniques in each country. Trying not to get into a Germans were smarter/dumber than the rest of the world argument here. In the 1930s the British pioneered the use of forged cylinder heads on radial engines because their CASTING technology was not equal to the US casting technology of the time. It was possible to forge longer or closer spaced fins than to cast them ON A PRODUCTION BASIS. US went to cast and forged heads using ganged slitting saws to cut the slots between fins following profiles.
Some engineers (showing bias?) claim that you use ball and roller bearings when you don't trust your plain bearings.

In some cases in the US ( and perhaps in other countries) the car makers were able to make valuable contributions into HOW parts were made even if they did not design the parts or make any changes to the engine itself.

 

[mhuxt]

More to the point, who's the girl in Lucky13's avatar, and how do I clone *her*?

I think I need about 4 or 5 for each room in the house.

 

[parsifal]

"cloning" is one thing, and quite difficult unless done with a licence 9and with that, co-operation from the parent cmpany). An altogether different proposition is substitute engines from existing supplies, eg the HS 129 using engines of French manufacture.

At the end of the day, trying to reverse engineer something as complex as an engine is probably theoretically possible, but from the standpoint of a war winning strategy, probably a complete dud. All that would happen would be the loss of a factory or more for an extended period as the cloning process was set up. And for all protagonists, but patrticulalry the Axis, it was always engines that limited the numbers of flyable aircraft

 

[vinnye]

I dont think the Packard production of the Merlin engine can be used as a model for re-engineering an engine.
I am pretty sure RR would have provided drawings / specifications / templates and support from the parent factories to make this happen as smootly as possible.
This was not available to German or Russian engineers, so if either were to embark on this - it would be much harder - not impossible but much harder.
When the USSR was negotiating for a licence to make RR Nene jet engines, they had technicians visit the production facilities and acquire material specimens to analyze for production.

 

[davebender]

Gnome-Rhône 14N - Wikipedia, the free encyclopedia
620 kg. Dry weight.
38.67 Liter displacement.
Carburetor. 87 octane fuel.
1,164 HP. Take off.

This engine might have potential for further development and power German aircraft such as Ar-196, Fw-200, Ju-252, He-111 etc. Acquiring a license to produce the French engine should not be difficult after June 1940.

 

[Shortround6]

I dont think the Packard production of the Merlin engine can be used as a model for re-engineering an engine.
I am pretty sure RR would have provided drawings / specifications / templates and support from the parent factories to make this happen as smootly as possible.

Rolls provided all of that and more (sample engines in running condition) BUT ALL the drawings had to be redone because American Industry used third angle projection and R-R used first angle.

Rolls did provide much more help than an enemy country trying to clone an engine would have but the change in drawings did cause a several month delay.

 

[Shortround6]

Gnome-Rhône 14N - Wikipedia, the free encyclopedia
620 kg. Dry weight.
38.67 Liter displacement.
Carburetor. 87 octane fuel.
1,164 HP. Take off.

This engine might have potential for further development and power German aircraft such as Ar-196, Fw-200, Ju-252, He-111 etc. Acquiring a license to produce the French engine should not be difficult after June 1940.

We have been over this before in other threads.

This engine had zip, nada, no way, zero potential for further development which is why the Gnome-Rhône company was working on the "R" model and was flying prototypes in 1940.

Changes or "developments" include not only the "two stage supercharger" which wiki has wrong (it wasn't, it was two speed though) but a new crankshaft and crankcase with three main bearings instead of two. I am not sure what other changes there were but the engine gained just about 200kg. in weight.

Germans were trying to use as many of the 14Ns as they could but sabotage (and/or very slow work) held production to 1/4-1/3 what the Germans planned/wanted.

 

[vinnye]

Shotround, I should have known that the drawings would need to be re-drawn in Third Angle Projectionn - I did an apprenticeship 35 years ago in design engineering!
This would indeed have taken some time!

 

[davebender]

Perhaps so but it's one of the few enemy engines Germany acquired early enough that it has potential to be copied. It's also already designed to metric measurements.

 

[Shortround6]

For the Germans it is senseless to "copy" this engine.

What is it really going to do that their existing engines will not do?

If "copied" it is either at the expense of engines already in production ( no net gain in total engines produced) or a special facility has to be build to produce it in which case using this new, fictitious facility to build Rhone 14N engines instead of more BMW 801s or some other engine is a waste of resources.

Using (or attempting to use) an existing French Factory already tooled up for for the 14N with an already trained labor force in place is a whole lot better of an idea than trying to "copy" the the 14N for construction in Germany by German workers.

It was always going to be a second line engine only slightly better than the BMW 132 and Bramo 323.

 

[davebender]

So was P&W R1830 yet we produced 173,000 of them.

Uber engines such as R2800 get most publicity but smaller engines are important too.

 

[The Basket]

Tupolev didnt want to clone the B-29 but Stalin did so no guesses who won there.

One must rememeber that by the first Tu-4 flight the B-29 had flown 5 years before and so the Soviets were copying obsolete technology. Although the Tu-4 was an important milestone in Soviet design and would become a fearsome weapon on its own right.

 

[GregP]

You're saying the R-1830 was a second-line engine?

Boeing, Consolidated, Douglas and Grumman might disagree along with a lot of B-17, B-24, PBY, C-47, SBD, and F4F pilots and crew chiefs, plus a few others that were produced but not in as great numbers. While the R-1830 wasn't in the forefront of developed power, I believe it was in the forefront of reliability and dependability.

 

[Shortround6]

So was P&W R1830 yet we produced 173,000 of them.

Uber engines such as R2800 get most publicity but smaller engines are important too.

Rather misses the point doesn't it?

Germans had two different 1000hp 9 cylinder radials of their own to begin with. "Cloning" a 1100-1200hp 14cylinder engine (that they already have the Factory for) gets them what in the grand scheme of things?

One less factory building Jumo 211/213s, or DB engines (including the 603?) or BMW 801s.

Please note that the Russian M-88 engine was developed from the Gnome 14K and may be considered a parallel development of the 14N.

Longevity of the Gnome engines may not have been their strong suit. The P&W R1830 was fully developed and was a long lived reliable engine even if a bit heavy.

Cloning or licencing is done when the local designers/manufacturers need a "step up" to catch up to world standard.

 

[cherry blossom]

If cloning is difficult, is it possible to reunite divergent lineages. For example, the Rhone-Gnome 14 R was a 14 cylinder radial with a bore of 146 mm (5.74 in) and a stroke of 165 mm (6.49 in). The Nakajima Ha 109 differed in having a bore of 146 mm and a stroke of 160 mm. Both ultimately derived independently from the 9 cylinder Bristol Jupiter which had a bore of 5.75 in and a stroke of 7.5 in. If we assume that Japan approached both the Vichy Government and the Germans in early July 1940 and asked if the Rhone-Gnome design team could move to Japan and continue development and the Germans said yes to try to strengthen Japan while the French said yes to enable then to continue development despite the Armistice conditions, could the ideas from both engines be combined to produce a better Ha 109?