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Thanks Calum, great information. I don't want to clutter up your thread but in short I've seen quotes from Pierre Clostermann and F/O Ronald Dennis discussing the Sabre IIB operating at 3,850 rpm and +13 lbs boost after being fitted with Rotol props. This would have been in 1945 with the 2nd TAF. I don't recall seeing any primary source documents verifying these operating settings. Bit of a puzzler.

Hmmm... I certainly cant corroborate that from the documents I have, but I cant say that means its not possible...as the better bearings were put in later
which "might" possibly have allowed it to be increased in boost.

My diary of David Greene (vandervell bearing engineer) has an entry on 5th Feb 1945:

"Reported that Sabres are now giving 2700 hp at 4200rpm with 18 lb boost and bearings are good."

Sadly I have no idea WHICH Sabre... of if thats data from operations or special testbed data.
 
You raise a valid point... I wont be able to get away with any tarted up Biggles stories from now on.... I`ve been really nervous waiting for reviews to come in.

I think realistically the only imminent publication might be a revised and slightly expanded editon next year if sales remain high. There were 3 archives
I was due to pilliage before Covid ruined it all, so might be some additional snippets to add one day.

Looking forward to reading the positive reviews, And as my boss used to say; "Great job! Now you have to do better."
 
You can ASK me whatever you like Tomo.

Excellent :)
On pg. 45 - "These three areas for improvement which Hooker had outlined were put into practice and resulted in the basis for the superchargers on the Merlin X, XX and 45 series engines, ..."

Was really Hooker's work incorporated on Merlin X, or this is misprint?
 
Excellent :)
On pg. 45 - "These three areas for improvement which Hooker had outlined were put into practice and resulted in the basis for the superchargers on the Merlin X, XX and 45 series engines, ..."

Was really Hooker's work incorporated on Merlin X, or this is misprint?

Well the bigger stuff like the central entry casing didnt come in until the 45 and XX, which is always easy to see from the outside of the casing. To confirm smaller changes will take me longer as my RR engineering records are not digitised yet (unlike the correspondance records), and it takes me a long while to sift through them. (At the RR engineering archive you cant use a camera, so its all on photocopies) I`ll try to check and come back to you.
 
Well the bigger stuff like the central entry casing didnt come in until the 45 and XX, which is always easy to see from the outside of the casing. To confirm smaller changes will take me longer as my RR engineering records are not digitised yet (unlike the correspondance records), and it takes me a long while to sift through them. (At the RR engineering archive you cant use a camera, so its all on photocopies) I`ll try to check and come back to you.

Hmm its not in my engineering documents either, I suspect it may be in my interview`s notebook with Dave Piggott at RRHT, I wont be able to get to that until later in the week. Its just about possible in editing that I`ve typed XXX and at some stage someone put a comma in, to make it X, XX but I`ll read my interview transcript with Dave and see.
 
Another remark I have is the BMW + RLM + radial engines saga, specifically what is written on pg. 109.

BMW signed the deal for both Hornet and Wasp series production with P&W on 3rd January 1928, per book 'BMW Flugtriebwerke'. (my take for the reasoning behind the deal - BMW didn't have anything resembling a modern engine in that time, the VI and the like being a spin-off of the ww1 vintage design practice). At the end, BMW made no Wasps.
The licence was worth for all of Europe bar British islands. Type tests of BMW-made Hornet were completed by 28th March 1930.

RLM was established 5 years later than the P&W deal was signed, thus RLM was could not play the part in BMW going air-cooled.
There was no Siemens and Bramo in the same slice of time. Siemens-Halske engine branch, that bough licence for Jupiter, was separated from Siemens holdings (Konzern) to became Bramo. Thus we have BMW being a competitor vs. either S-H or Bramo, not a co-operative for number of years.
Now RLM enters (winter of 1936/37, per book 'Flugmotoren und Strahltriebwerke') and demands that BMW phases out the liquid-cooled engines. BMW and Bramo sign a deal about joint development of air-cooled engines in 30th September 1938. BMW takes over the Bramo in July 1939, stipulating that 1-row radials are to be prerogarive of Berlin branch, and 2-row radials are Muenchen's responsibility.
There was no 'arguing over' at BMW what engine will power the Fw 190 that was in testing phase - it is going to be a 2-row radial BMW engine. Having messed up the BMW 139 (in development from 1936), mostly due to crankshaft having all 3 bearings between the crank throws (!), they redesigned it into the 801.

Sorry if this sounds long-winded :)
 
Another remark I have is the BMW + RLM + radial engines saga, specifically what is written on pg. 109.

BMW signed the deal for both Hornet and Wasp series production with P&W on 3rd January 1928, per book 'BMW Flugtriebwerke'. (my take for the reasoning behind the deal - BMW didn't have anything resembling a modern engine in that time, the VI and the like being a spin-off of the ww1 vintage design practice). At the end, BMW made no Wasps.
The licence was worth for all of Europe bar British islands. Type tests of BMW-made Hornet were completed by 28th March 1930.

RLM was established 5 years later than the P&W deal was signed, thus RLM was could not play the part in BMW going air-cooled.
There was no Siemens and Bramo in the same slice of time. Siemens-Halske engine branch, that bough licence for Jupiter, was separated from Siemens holdings (Konzern) to became Bramo. Thus we have BMW being a competitor vs. either S-H or Bramo, not a co-operative for number of years.
Now RLM enters (winter of 1936/37, per book 'Flugmotoren und Strahltriebwerke') and demands that BMW phases out the liquid-cooled engines. BMW and Bramo sign a deal about joint development of air-cooled engines in 30th September 1938. BMW takes over the Bramo in July 1939, stipulating that 1-row radials are to be prerogarive of Berlin branch, and 2-row radials are Muenchen's responsibility.
There was no 'arguing over' at BMW what engine will power the Fw 190 that was in testing phase - it is going to be a 2-row radial BMW engine. Having messed up the BMW 139 (in development from 1936), mostly due to crankshaft having all 3 bearings between the crank throws (!), they redesigned it into the 801.

Sorry if this sounds long-winded :)

Point #1 is wrong, because you have misunderstood my book, the timeline is as the picture below:

Point #2 is in the book from original BMW archival sources, I`m not interested what other books may say. (see page 104 - surprising as you are complaining about
a point on pg109 when the answer is there for you on pg104.

"Until autumn of 1938 there was a co-operative with Bramo for the 323 and 329..." (see BMW internal history of the BMW 800 engine)
1606218287003.png


I understand what you are trying to say with third point, but until you have understood the 139>800>801 development saga I dont think you
are in a position to be saying my book is wrong. A lot of 800 design aspects were carried over to the 801 but there was clearly massive
discussion about it, and it was clearly possible that the 801 might have been a 2-row 800, more than a new engine. Thats
really what I meant.

I admit that all the points you bring up could have been better worded, however, its difficult to give a detailed back-story to every single point. If we do a 3rd printing,
I`ll maybe clarify the BMW air cooling timeline, the point that Hookers work on the X was just the impeller and that the discussion about Fw 190 engine
was really an internal BMW affair about what from the 800 single row they would "merge" into the 801. Note that the 800 (I have no photos) appears to have
had some more advanced features than the 801, which were judged to be too time consuming to integrate into the 801.

Regarding BMW water cooled V12s, the BMW-112 and 115 were just about as advanced as a DB600 - they also had the 116 and 117. It was a huge
U-turn to throw all that away.

"GDC-7/10"
1606218945271.png
 
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Excellent :)
On pg. 45 - "These three areas for improvement which Hooker had outlined were put into practice and resulted in the basis for the superchargers on the Merlin X, XX and 45 series engines, ..."

Was really Hooker's work incorporated on Merlin X, or this is misprint?

Just checked my research notes, interview with Dave Piggott, confirms that Hooker`s first major influence was the reduced tip height impeller, first implimented on the Merlin X.

The XX and 45 were the first to get the other goodies, such as the central entry housing. So no, not a mis-print.
WIN_20201124_14_08_00_Pro.jpg
 
Point #1 is wrong, because you have misunderstood my book, the timeline is as the picture below:

Point #2 is in the book from original BMW archival sources, I`m not interested what other books may say. (see page 104 - surprising as you are complaining about a point on pg109 when the answer is there for you on pg104.

"Until autumn of 1938 there was a co-operative with Bramo for the 323 and 329..." (see BMW internal history of the BMW 800 engine)
I understand what you are trying to say with third point, but until you have understood the 139>800>801 development saga I dont think you are in a position to be saying my book is wrong. A lot of 800 design aspects were carried over to the 801 but there was clearly massive discussion about it, and it was clearly possible that the 801 might have been a 2-row 800, more than a new engine. Thats really what I meant.

I admit that all the points you bring up could have been better worded, however, its difficult to give a detailed back-story to every single point. If we do a 3rd printing, I`ll maybe clarify the BMW air cooling timeline, the point that Hookers work on the X was just the impeller and that the discussion about Fw 190 engine was really an internal BMW affair about what from the 800 single row they would "merge" into the 801. Note that the 800 (I have no photos) appears to have had some more advanced features than the 801, which were judged to be too time consuming to integrate into the 801.

Regarding BMW water cooled V12s, the BMW-112 and 115 were just about as advanced as a DB600 - they also had the 116 and 117. It was a huge
U-turn to throw all that away.

Thank you for the exhaustive reply.
Yes, I'd second to the notion that the BMW excerpt on pg. 109 might've been better worded, especially the RLM + BMW + P&W part. That BMW have had to abandon their new water cooled engines was a loss to them, that loss happened before Fw 190 was borne.

Just checked my research notes, interview with Dave Piggott, confirms that Hooker`s first major influence was the reduced tip height impeller, first implimented on the Merlin X.

The XX and 45 were the first to get the other goodies, such as the central entry housing. So no, not a mis-print.

Thank you again.
 
Thank you for the exhaustive reply.
Yes, I'd second to the notion that the BMW excerpt on pg. 109 might've been better worded, especially the RLM + BMW + P&W part. That BMW have had to abandon their new water cooled engines was a loss to them, that loss happened before Fw 190 was borne.

Thank you again.

Yes, accepted I could re-word a couple of bits, as if you have misconstrued the meaning - probably others have too.

Just for fun, thats the BMW 112
WIN_20201124_14_07_07_Pro.jpg
 
Please, could you anticipate title of Italian edition and its previewed issue date?

No exact idea, as you can appreciate its a gigantic job to translate...

I would expect perhaps six months from now; but thats down to the translator and suchlike... its hard to be definite.
 

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