March until October of 1940: fighters' ranking

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The British propeller situation was quite a mess.
They were working on and experimenting with the better propellers as can be seen by the reports, but just because one (or several) aircraft were tested with propeller X doesn't mean that all production aircraft started to be fitted with them in a few days. Much like the trial taking place in Jan 39 but first production aircraft getting one in late 39 but it doesn't say if production totally switched over. Let alone aircraft already in service. The DH refit program was well known and involved hundreds of aircraft in June of 1940. Perhaps not the few weeks I stated but since the British and Germans can't seem to agree on when it started (July 10th or Aug 13th) it was more a matter of weeks than months.

I have no figures for Hurricane production as to how many got Rotol props in the winter of 1939/40 and how many got DH 2 pitch props. Were both Hurricane production lines interchanging propellers or was it just one production line?
Likewise does anybody know what Supermarine was doing? Were there enough Rotol props to switch over at a certain date or were planes built in batches with whatever prop they had available at the time?

For the Germans you had the 109s slowly being rebuilt with later engines or new 109s (like the 109E-7) showing up with DB601E engines.
It could well be that the E-7 and the re-engined planes used the old propellers and the new props waited for the 109Fs.
 
The British propeller situation was quite a mess.
They were working on and experimenting with the better propellers as can be seen by the reports, but just because one (or several) aircraft were tested with propeller X doesn't mean that all production aircraft started to be fitted with them in a few days. Much like the trial taking place in Jan 39 but first production aircraft getting one in late 39 but it doesn't say if production totally switched over. Let alone aircraft already in service. The DH refit program was well known and involved hundreds of aircraft in June of 1940. Perhaps not the few weeks I stated but since the British and Germans can't seem to agree on when it started (July 10th or Aug 13th) it was more a matter of weeks than months.

I have no figures for Hurricane production as to how many got Rotol props in the winter of 1939/40 and how many got DH 2 pitch props. Were both Hurricane production lines interchanging propellers or was it just one production line?
Likewise does anybody know what Supermarine was doing? Were there enough Rotol props to switch over at a certain date or were planes built in batches with whatever prop they had available at the time?

For the Germans you had the 109s slowly being rebuilt with later engines or new 109s (like the 109E-7) showing up with DB601E engines.
It could well be that the E-7 and the re-engined planes used the old propellers and the new props waited for the 109Fs.
There seems to have been some resistance to CP propellers from the British fighter manufacturers.
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This is from Fight magazine in 1935. Unfortunately, I do not have the rest of the article.

Attached is a presentation on the history of variable pitch propellers
 

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There seems to have been some resistance to CP propellers from the British fighter manufacturers.
This is from Fight magazine in 1935. Unfortunately, I do not have the rest of the article.

Attached is a presentation on the history of variable pitch propellers
Is it possible to have a hi-res copy of the 'Flight' article somewhere?
 
Britain was the last major power do adopt constant speed propellers, and quite a few minor ones beat them to it also.

Please note that for multi engine aircraft constant speed does not mean fully feathering propellers. That is a separate feature and requires different hubs.
Nobody has any idea of how many British aircrew on multi-engined aircraft were lost due to crappy propellers.

British plan was to shut down the malfunctioning/damaged engine and activate a "Brake" fitted to the propeller shaft to stop the propeller from rotating (and further thrash the engine/propeller combination around) but the propeller blades would be in the coarse blade angle causing considerable drag compared to prop blades that were lined up with a the aircraft direction of travel.
 
I remember reading how Doug Bader crashed trying to take off in the middle of an air raid because his Hurricane was set at the wrong pitch. So the change-over was not complete before the start of BoB.
 
Hi
The book 'British Commercial Aircraft, Their Evolution, Development and Perfection 1920-1940' by Arthur W J G Ord-Hume, includes short summaries of propeller companies, including the following:
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I believe the priority for VP and CS propellers was originally multi-engine types like the Vickers Wellington, although the pre-war airliner de Havilland DH95 Flamingo also had CS propellers.

Mike
 
Hi
The book 'British Commercial Aircraft, Their Evolution, Development and Perfection 1920-1940' by Arthur W J G Ord-Hume, includes short summaries of propeller companies, including the following:
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I believe the priority for VP and CS propellers was originally multi-engine types like the Vickers Wellington, although the pre-war airliner de Havilland DH95 Flamingo also had CS propellers.

Mike
The primary reason I gave you a bacon was for "banana cam".
 
Hi
The wartime book 'Aeronautical Engineering' Edited by R A Beaumont, Chapter XIII 'Airscrews, by A V Cleaver contains a fair amount of information on VP mechanisms including the different types in use:
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Mike
 
Hi
'The Spitfire Story' by Alfred Price, on pages 81-82 has three tests on Spitfire Is with different propellers. The improvements in take-off runs is significant and probably a good reason for the RAF to prioritise both two-pitch and CS for heavily laden bombers, which would have needed rather longer take-off runs than fighters:
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Mike
 
I noticed that this particular aeroplane incorporated a small electrical switch on the floor, marked "Prop: Auto/Manual", but it was wired to the Manual position. I was later told that this aeroplane never flew operationally with the system operative.
I can see how you might interpret that as being "Bf 109s" in general, but my interpretation is that the particular aircraft was not flown operationally owing to the use of the word "this" in the sentence, as opposed to "these" or "this type of"...
 
The British propeller situation was quite a mess.
They were working on and experimenting with the better propellers as can be seen by the reports, but just because one (or several) aircraft were tested with propeller X doesn't mean that all production aircraft started to be fitted with them in a few days. Much like the trial taking place in Jan 39 but first production aircraft getting one in late 39 but it doesn't say if production totally switched over. Let alone aircraft already in service. The DH refit program was well known and involved hundreds of aircraft in June of 1940. Perhaps not the few weeks I stated but since the British and Germans can't seem to agree on when it started (July 10th or Aug 13th) it was more a matter of weeks than months.

No, things didn't move very swiftly and for the Hurricane in general it was dependent on when the C/S props were put on production aircraft on different production lines. I've seen reference to Gloster aircraft reaching the squadrons so fitted with Rotol props in March 1940, so it does depend on when changes get made on production lines. Remember, the Hurricane was a major production effort and was at the time the recipient of the largest single order for an individual aeroplane type, 600 examples, which meant satellite factories had to be built.

This was at a time when production was not particularly fast because it was peacetime and the concept of satellite factories building other people's aircraft was not widespread. Getting production to keep up with sudden demand because of war had quite an impact on the industry, some firms workers refused to work harder and went on strike - Avro was one firm where industrial action was prevalent because the workers were driven quite hard.

Things took time to implement and whilst it is easy to criticise, the German system was just as disorganised, but we don't hear that much about it. Bf 109s were certainly not standardised across factories and the same issues with production aircraft occurred across different factories with different manufacturers.

According the the records and the Big Book of Spitfires, the DH C/S prop refit drive took part from late June to late July 1940, after which at the end of July, (according to the book) every in-service Spitfire had a C/S prop. The refit didn't take long to do and it was a matter of supplying the equipment for the fit to be done at aerodrome around the country. Remember, there was a war on...
 
Britain was the last major power do adopt constant speed propellers, and quite a few minor ones beat them to it also.

It was a British manufacturer that designed and produced the first C/S prop though. Hele-Shaw Beacham prop of the mid 20s, which from the sections Mike produced tells a little about the prop, although they don't mention exactly why it wasn't adopted wholesale. Also, can you justify that? The Germans fitted their C/S prop to their fighters after the RAF. The reality was that there were not many C/S props fitted to frontline fighters and bombers at the outbreak of WW2. VP props, yes, but not C/S.

As far as VP props are concerned, Armstrong Whitworth Whitleys, Bristol Blenheims and Fairey Battles entered service with VP props in 1937, the Short Empire Class civilian boats had them in 1936. As I've mentioned, of the RAF's frontline aircraft, only its fighters had those big wooden club propellers by the outbreak of WW2.

The book 'British Commercial Aircraft, Their Evolution, Development and Perfection 1920-1940' by Arthur W J G Ord-Hume, includes short summaries of propeller companies, including the following:

Thanks for posting, Mike, the Hele-Shaw Beacham (HSB shortened so I don't have to write it in full everytime) prop was originally developed because Hugh Burrows of Gloster approached the two gents with the idea of building a hydraulically actuated propeller in 1925. Gloster acquired the design rights in 1926 and had the type fitted to Gamecock aeroplanes, which proved that the idea worked. HSB couldn't interest engine manufacturers because they argued that increased power could do the job, apparently and the Air Ministry was luke-warm to the proposal because of the extra weight and the complexity for the pilot during operation of the prop in-flight. Gloster remained a supporter, but the firm was small potatoes at the time. In 1929 Gloster marketed the idea at the International Aero Exhibition at Olympia, where, a certain Mr Tom Hamilton saw it... It is worth noting that the first HS two-position prop did not come out until 1930. The Bristol connection didn't occur until Gloster sold the propeller concern to it and Rolls-Royce in 1936, the two firms creating Rotol...
 
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